EPAC 2004 - List of Keywords

A B C D E F G H I K L M O P Q R S T U V W

antiproton

Paper	Title	Other Keywords	Page
TUPLT020	High Intensity Uranium Operation in SIS18	plasma, laser, focusing, beamloading	1180
	P.J. Spiller, K. Blasche, P. Hülsmann, A. Krämer, H. Ramakers, H.R. Sprenger GSI, Darmstadt
	For the present experiment program and the planned international accelerator facility at GSI, the space charge limit of SIS18 for highly(4x1010) and intermediate (2.7x1011) charged uranium ions shall be reached within the next four years. Furthermore, measures to increase the repetition- and ramp rate up to 4 Hz with 10 T/s have been progressed. The present state of intensities per cycle and the limitations will be described. In connection with the planned enhancement of heavy ion intensities, protection, interlock and diagnostic systems, especially for the injection- and extraction devices have been prepared. Special attention is drawn on the insights which were achieved with respect to the operation at dynamic vacuum conditions. Results of R&D work with the goal to increase the intensity threshold and to improve the beam life time will be summarized. Furthermore, the specific upgrade program and schedule for the SIS18 booster mode will be presented.

TUPLT021	Heavy Ion Beam Transport in Plasma Channels	ion, laser, beamloading, betatron	1183
	S. Neff, D.H. Hoffmann, R. Knobloch TU Darmstadt, Darmstadt C. Niemann, D. Penache, A. Tauschwitz GSI, Darmstadt S. Yu LBNL, Berkeley, California
	The transport of heavy ion beams in high current discharge channels is a promising option for the final beam transport in a heavy ion fusion reactor. The channel provides space-charge neutralization and an azimuthal magnetic field of several tesla, thereby allowing for transporting high current ion beams. The possibility to heat the hohlraum target with only two ion beams simplifies the reactor design significantly. Therefore channel transport is studied as part of the US fusion reactor study as an alternative to neutralized ballistic focusing. We have created 1 m long discharge channels and studied the channel development and stability. In addition, we have carried out proof-of-principle transport experiments using the UNILAC facility at the Gesellschaft für Schwerionenforschung. The experiments demonstrate the feasibility of plasma channel transport. Our transport experiments with low current beams are supplemented by simulations for high current beams. These simulations show the possibility of transporting particle currents of up to 60 kA.

TUPLT022	Beam Dynamics Simulations at the S-DALINAC for the Optimal Position of Beam Energy Monitors	ion, beamloading, betatron, cathode	1186
	B. Steiner, W.F.O. Müller, T. Weiland TEMF, Darmstadt A. Richter TU Darmstadt, Darmstadt
	The S-DALINAC is a 130 MeV superconducting recirculating electron accelerator serving several nuclear and radiation physics experiments as well as driving an infrared free-electron laser. For the experiments an energy stability of 1·10^-4 should be reached. Therefore noninvasive beam position monitors will be used to measure the beam energy. For the measurement the different flight time of the electrons to the ideal particle are compared, that means in the simulations the longitudinal dispersion of the beam transport system is used for the energy detection. The results of the simulations show that it is possible to detect an energy difference of 1·10^-4 with this method. The results are also proven by measurements.

TUPLT023	A New Ion Beam Beam Facility for Slow Highly Charged Ions	ion, electron, beamloading, betatron	1189
	G. Zschornack, S. Landgraf TU Dresden, Dresden S. Facsko, D. Kost, W. Möller, H. Tyrroff FZR, Dresden F. Grossmann, U. Kentsch, V.P. Ovsyannikov, M. Schmidt, F. Ullmann Leybold Vacuum Dresden, Dresden
	A new ion beam facility for slow highly charged ions is presented. It will provide slow highly charged ions from an Electron Cyclotron Resonance (ECR) ion source as well as very highly charged ions at lower ion currents from an Electron Beam Ion Trap (EBIT). As ECR ion source a SUPERNANOGAN source* is applied. The Dresden EBIT*, a room-temperature EBIT, is used to produce comparatively low currents of very highly charged ions. This very compact and long-term stable device is producing highly charged ions at ultimate low costs. The Dresden EBIT working with electron energies up to 15 keV at electron currents up to 50 mA is able to produce bare nuclei up to nickel as Fe²⁶⁺ or Ni²⁸⁺, helium-like ions for medium Z such as Ge³⁰⁺ or Kr³⁴⁺ and neon-like ions for elements of the high-Z region such as Xe⁴⁴⁺ or Ir⁶⁷⁺. The ion currents extracted from the Dresden EBIT are typically in the range of some nA per pulse. With the new ion beam facility outstanding possibilities for a wide range of investigations are opened up in areas such as surface analysis, materials science and nanotechnology as well as for basic research in different fields as for instance in atomic and solid state physics. The Pantechnik Catalogue, August 2001 Edition, Caen 2001, France **V.P.Ovsyannikov, G.Zschornack; Review of Scientific Instruments, 70 (1999) 2646

TUPLT024	A Comparison of High Current Ion Beam Matching from an Ion Source to a RFQ by Electrostatic and by Magnetic Lenses	ion, electron, beamloading, betatron	1192
	R. Becker, R.A. Jameson, A. Schempp IAP, Frankfurt-am-Main T. Hata, N. Hayashizaki, H. Kashiwagi, K. Yamamoto RLNR, Tokyo T. Hattori, M. Okamura, A. Sakumi RIKEN, Saitama
	In order to improve the ?direct? injection scheme of the Riken Nd-YAK-laser driven ion source into a RFQ rf-accelerator, several basic methods have been investigated and compared, in order to transform the initially divergent ion beam into a convergent one, needed for matching the high current (100 mA C⁶⁺) ion beam at an energy of 100 keV to a RFQ. From the point of power supplies and break down characteristics, the simplest solution is a decelerating electrostatic lens, with the decelerating electrode operated on ion source potential. Due to the strong divergence of the ions beam after acceleration, this lens will be filled to an aperture, which causes strong aberrations. Therefore, we also investigated to use an accelerating potential on the lens electrode. This reduces significantly the filling of the lens and the emittance growth is only a factor of 3, as compared to the decelerating lens with a factor of 30! Finally we have been looking also into a magnetic matching system, which can match the ion beam to the RFQ with virtually no emittance growth.

TUPLT025	Matching of a C⁶⁺ Ion Beam from a Laser Ion Source to a RFQ	electron, ion, beamloading, betatron	1195
	R. Becker, R.A. Jameson, A. Schempp IAP, Frankfurt-am-Main T. Hattori RIKEN, Saitama N. Hayashizaki, H. Kashiwagi RLNR, Tokyo M. Okamura RIKEN/RARF/CC, Saitama K. Yamamoto RIKEN/RARF/BPEL, Saitama
	A laser ion source, driven by a Nd-YAG laser can provide more than 100 mA of C⁶⁺ ions for a duration of about 1 μs, which is well matching the task of single-turn injection into synchrotrons for hadron tumor therapy with light ions. The ?direct? injection scheme has been improved by providing a design, which reduces the surface field strength to less than 30 kV/cm on all critical parts on relative negative potential. The new design keeps the advantage of divergent ion emission and acceleration, which seems to be the only way to keep the surface fields in limits, but includes a decelerating electrostatic lens on birth potential of the ions to refocus the emerging ion beam to the RFQ entrance. The whole design is very compact and allows for electrostatic steering between the ion source and the RFQ.

TUPLT026	High Current Ion Beams at Frankfurt University	electron, beamloading, betatron, cathode	1198
	M. Droba, O. Meusel, U. Ratzinger, K. Volk IAP, Frankfurt-am-Main
	A new building for the physics faculty at the Goethe-University in Frankfurt is under construction including an experimental hall. The Institute of Applied Physics IAP has started development of a high current ion beam facility consisting of a high voltage terminal(150 kV,I_beam < 300 mA,H-,p,Bi+), a 10 MV linear rf accelerator and a high current storage ring for 150 keV beams. The 150 kV terminal equipment is already ordered while the subsequent units are in the design stage. The storage ring will use a stellarator-like magnetic configuration to allow for a high degree of space charge compensation by electrons. The facility will allow high current beam investigations as well as experiments in fields of plasma, nuclear and atomic physics.

TUPLT027	Status of the HITRAP Decelerator Linac at GSI	electron, linac, beamloading, betatron	1201
	C.A. Kitegi, A. Bechtold, U. Ratzinger, A. Schempp IAP, Frankfurt-am-Main T. Beier, L. Dahl, C. Kozhuharov, W. Quint, M. Steck GSI, Darmstadt S. Minaev ITEP, Moscow
	Within the European Network HITRAP (heavy Ion trap) trapped and cooled higly charged ions up to U⁹²⁺ will become avilable for a variety of attractive experiments in atomic physics. Heavy ions are produced, accelerated and stripped in the GSI accelerator complex and are stored in the ESR down to 4 MeV/u. To be captured in HITRAP, ions have to be decelerated to energies below 6 keV/u. The decelerator proposed to achieve these energies is a combination of an IH Drift tube cavity operating in the H11(0) mode and a RFQ. The operating frequency is 108.408MHz . The A/q range of the linac is up to 3. A very efficient deceleration by up to 11 MV along the 2.7 m long IH cavity with a rf power of 200kw is achieved by applying the KONUS beam dynamics. The deceleration from 500 A.keV down 6A.keV is provided by a 1.8 m long 4-rod RFQ.The beam dynamics as well as the cavity design of that linac will be described.The decelerator linac will be installed in the reinjection beam line and is being developed in collaboration between GSI and the Frankfurt University .

TUPLT028	Development of Finger Drift Tube Linacs	electron, linac, focusing, beamloading	1204
	K.-U. Kuehnel, A. Schempp IAP, Frankfurt-am-Main C.P. Welsch MPI-K, Heidelberg
	At higher particle energies the efficiency of RFQs decreases and DTL structures in combination with magnetic quadrupoles are used. One approach at IAP is the combination of RFQ and DTL. To compensate the defocusing effects of a DTL structure, the accelerating gaps of a spiral loaded cavity were equiped with small focusing fingers. These fingers arranged in a quadrupole symmetry provide an additional focusing field component. The beam dynamics of such a cavity has been studied with PARMTEQ. Simulations of the rf properties have been done using microwave studio. A prototype of a spiral loaded cavity with finger drift tubes has been built and low power measurement were made. Results of the calculations as well as low level and bead pertubation measurements are presented in this contribution.

TUPLT029	Status of the Superconducting D⁺-CH-DTL Design for IFMIF	electron, linac, focusing, beamloading	1207
	A.C. Sauer, H. Deitinghoff, H. Klein, H. Liebermann, O. Meusel, H. Podlech, U. Ratzinger, R. Tiede IAP, Frankfurt-am-Main
	Within the IFMIF project (International Fusion Materials Irradiation Facility) a high current D⁺-linac operated in cw mode has to be developed. The acceleration of a 125 mA D⁺-beam from 0.1 MeV up to 40 MeV must be performed at an extremely low loss rate (0.1-0.2 microA/m). One optional layout of the acceleration facility consists of a high current ion source, low energy beam transport (LEBT), Radio-Frequency-Quadrupol (RFQ) followed by a superconducting H-type DTL. The matching of the beam between subsequent linac sections has to be carefully optimized to avoid an activation of the structures. Actual beam dynamics simulations for such a linac design including parameter errors of components are reported. Consequences for the LEBT- and RFQ-section are discussed.

TUPLT032	The Frankfurt Funneling Experiment	electron, linac, focusing, beamloading	1213
	H. Zimmermann, U. Bartz, N. Mueller, A. Schempp, J. Thibus IAP, Frankfurt-am-Main
	The Frankfurt Funneling Experiment is a scaled model of the first funneling stage of a HIF driver to gather experiences in the funneling technique. It is a procedure to multiply beam currents at low energies in several stages. In each stage two beam lines are combined to a common beam line. The funneling technique is required for new proposed high current accelerator facilities like HIDIF. The main goal is to prevent emittance growth during the funneling process. Our experiment consists of two ion sources, a Two-Beam RFQ accelerator, two different funneling deflectors and a beam diagnostic equipment system. We have demonstrated the principle of funneling with both deflector types. But the measurements have shown a bad matching of the RFQ to the funneling deflector. Now with our new RFQ electrode design we achieve a special three dimensional matching to the deflector. The new results of our measurements and simulations will be presented.

TUPLT033	RF Design of the MAFF IH-RFQ Power Resonator	electron, focusing, beamloading, betatron	1216
	M. Pasini, D. Habs, O. Kester LMU, München T. Sieber CERN, Geneva
	The low energy part of the LINAC of the MAFF facility will be an IH-RFQ cavity with 101.28 MHz resonance frequency. The RF design of the cavity has been completed, including design calculations and model measurements. The RFQ is designed to deliver ions of A/q = 6.5 up to 300 keV/u to be injected into the following LINAC. The structure chosen was an IH type of resonator since it was demontrated to have a better shunt impedance. The required voltage between the electrodes is 70kV and the operation mode is pulsed with a duty cycle of 10%. The structure will be made out from bulk copper in order to improve the shunt impedance and hence to allow not direct cooling on the electrodes. The optimizazion of the several parameters of the structure, and the technique for tuning the voltage distribution are presented in this paper. Measurements with a short model will be shown as well.

TUPLT034	Beam Dynamics Studies for the Low Energy Section at MAFF	electron, focusing, beamloading, betatron	1219
	M. Pasini, D. Habs, O. Kester LMU, München A. Bechtold, A. Schempp IAP, Frankfurt-am-Main
	For the LINAC of the Munich accelerator for fission fragments (MAFF) a new scheme for the low energy section has been proposed in order to fulfill new experimental requirements, such as time spacing between bunches and low longitudinal emittance. The proposed solution consists in a combination of an external multi-harmonic buncher with a "traditional" RFQ with a shaper and an adiabatic bunching section included where the employment of the external buncher is upon request from the experiment. The matching section downstream the RFQ has been re-designed in order to allow room for the installation of a beam cleaning section and to a proper injection into the following DTL. Details about the optics and beam dynamics studies of the low energy section are presented in this paper.

TUPLT035	Online Calculation of the Beam Trajectory in the HERA Interaction Regions	electron, focusing, beamloading, betatron	1222
	F. Brinker DESY, Hamburg
	During the HERA luminosity upgrade the new super conducting mini beta quadrupoles have been placed inside the experiments for final focussing and separation of the lepton and proton beams. The synchrotron radiation of up to 12 kW produced in these magnets passes through the detector and is absorbed behind the experiments. In order to avoid background events from synchrotron radiation it is a mandatory to adjust precisely the beam trajectory before and inside the detector. A procedure has been developed to calculate the trajectory in the interaction regions. With a beam-based alignment the offsets of the beam with respect to the quadrupoles is measured. From this measurement the offsets of the quadrupoles and of the beam position monitors are fitted. With the knowledge of these offsets the trajectory of the beam is calculated with high precision. The display of the trajectory is online available as an operational tool for beam steering and background optimization.

TUPLT036	Optimization of Low Emittance Lattices for PETRA III	lattice, electron, focusing, beamloading	1225
	W. Decking, K. Balewski DESY, Hamburg
	The reconstruction of the existing 2.3 km long storage ring PETRA II into a 3rd generation synchrotron light source (PETRA III) calls for an horizontal emittance of 1 nm rad. In addition the on- and off-momentum dynamic acceptance should be large to ensure sufficient injection efficiency and beam lifetime. We present three different types of lattices for the arcs of PETRA: a so-called TME lattice and a FODO lattice which both are newly designed to reach the specified emittance and the present FODO lattice with damping wigglers. The different lattice types have been compared through tracking calculations, including wiggler nonlinearities. Only the relaxed FODO lattice with damping wigglers meets the acceptance goals.

TUPLT037	Dispersion Correction in HERA	lattice, electron, focusing, beamloading	1228
	J. Keil, W. Decking DESY, Hamburg
	The electron-proton collider HERA at the DESY laboratory in Hamburg has been in operation since 1991. After the luminosity upgrade of HERA in 2001 the control of the horizontal and vertical dispersion function of the positron beam became more important than before. Deviations from the design dispersion in the horizontal plane can change the emittance of the electron beam significantly thus leading to a reduction of the luminosity. For optimizing the polarization of the electron beam the reduction of vertical orbit and dispersion deviations is important. In this paper the combined dispersion and orbit correction in HERA is described and first results are reported.

TUPLT038	Closed Orbit Correction and Orbit Stabilisation Scheme for the 6 GEV Synchrotron Light Source PETRA III	lattice, electron, focusing, beamloading	1231
	G.K. Sahoo, K. Balewski, W. Decking, Y.L. Li DESY, Hamburg
	PETRA III is a 6 GeV synchrotron light source being reconstructed out of the existing storage ring PETRA II. It will have a horizontal beam emittance of 1nm.rad and a 1% emittance ratio. Since the vertical beam sizes are ~5?10 micron in the low gap undulators sections the beam position stability requirement in the vertical plane is between 0.5 and 1 micron whereas the stability requirement in the horizontal plane is more relaxed. In this paper determination of golden orbit in the presence of magnetic field errors and magnet misalignments and correction of vertical spurious dispersion is discussed. A scheme of slow and fast orbit correction using the SVD algorithm has been developed. The distribution of monitors and the location of slow and fast correctors are reported. Estimations of the parameters of the fast orbit feedback have been derived from present measurements on PETRA II.

TUPLT039	An Electrostatic Quadrupole Doublet with an Integrated Steerer	lattice, electron, beamloading, damping	1234
	C.P. Welsch, M. Grieser, J. Ullrich MPI-K, Heidelberg C. Glaessner IAP, Frankfurt-am-Main
	Electrostatic storage rings have proven to be a valuable tool for atomic and molecular physics Due to the mass independence of the fields in the bending and focusing elements, different kinds of ions with the same charge/energy ratio from light protons to very heavy biomolecules, can be stored with the same field setup. The transverse dimensions of the circulating beam are controlled by electrostatic quadrupole doublets or triplets. It is essential that the fields in these lenses can be adjusted independently one from another to allow an exact control of the stored ions. In this paper, first an overview of the principle of electrostatic lenses is given. After a short discussion of fringe field effects, the results of field calculations are presented and the final layout of an electrostatic quadrupole doublet with an integrated steerer as it will be used in future electrostatic storage rings in Frankfurt and Heidelberg is discussed.

TUPLT040	CSR - a Cryogenic Storage Ring at MPI-K	ion, beamloading, damping, betatron	1237
	C.P. Welsch, J. Crespo López-Urrutia, M. Grieser, D. Orlov, C.D. Schroeter, D. Schwalm, J. Ullrich, A. Wolf, R. von Hahn MPI-K, Heidelberg X. Urbain UCL CRC, Louvain-la-Neuve D. Zajfman Weizmann Institute of Science, Physics, Rehovot
	A small cryogenic storage ring is planned to be developed at MPI-K, Heidelberg. The energy in the machine will be variable from 300 keV > down to 20 keV. Electron cooling will be applied to produce a high quality ion beam. The ring shall accommodate slow, vibrationally and rotationally cooled molecular ions and highly charged ions from the EBIT ion source. Moreover, it will serve as a test facility for the low-energy antiproton ring planned within the FLAIR collaboration to be installed at the future GSI facility. A number of technological challenges have to be handled: Especially highly charged ions require a vacuum in the order below 10^-13 mbar to achieve reasonable lifetimes. Therefore - and for enabling experiments with rotationally cold molecules - the complete machine will be cooled down to below 10 K. Moreover, experiments with reaction microscopes to determine the full kinematics of ion- (antiproton-) atom or molecule collisions require a bunched operation with a bunch length below 2 ns. The optical elements of the machine and the lattice functions are given and first ideas about the vacuum chamber design are described in this paper.

TUPLT041	Ultra-low Energy Antiprotons at FLAIR	ion, beamloading, damping, betatron	1240
	C.P. Welsch, M. Grieser, D. Orlov, J. Ullrich, A. Wolf, R. von Hahn MPI-K, Heidelberg
	The Future Accelerator Facility for Beams of Ions and Antiprotons at Darmstadt will produce the highest flux of antiprotons in the world. So far it is foreseen to accelerate the antiprotons to high energies (3-15 GeV) for meson spectroscopy and other nuclear and particle physics experiments in the HESR (High Energy Storage Ring). Within the planned complex of storage rings, it is possible to decelerate the antiprotons to about 30 MeV kinetic energy, opening up the possibility to create low energy antiprotons. In the proposed FLAIR facility the antiprotons shall be slowed down in a last step from 300 keV to 20 keV in an electrostatic storage ring (USR) for various in-ring experiments as well as for their efficient injection into traps. In this energy range - especially if one thinks about realizing a real multi-purpose facility with not only antiprotons, but also various highly-charged radioactive ions to be stored and investigated - electrostatic storage rings have clear advantages compared to their magnetic counterparts. In case one envisions to even approach the eV range, electrostatic machines are the only possible choice. This contribution presents the layout and design parameters of the USR.

TUPLT042	Ring of FIRE	ion, beamloading, damping, betatron	1243
	C.P. Welsch, J. Ullrich MPI-K, Heidelberg R. Doerner, H. Schmidt-Boecking IKF, Frankfurt-am-Main C. Glaessner, K.-U. Kuehnel, A. Schempp IAP, Frankfurt-am-Main
	A small electrostatic storage ring is the central machine of the Frankfurt Ion stoRage Experiments which will be build up at the new Stern-Gerlach-Center of Frankfurt university. With ion energies up to 50 keV it will allow new methods to analyze complex many-particle systems from atoms to very large bio molecules. The high luminosity of the beam allows measurements with many orders of magnitude better resolution compared to traditional measurements. It will be combined with existing experiments, like the reaction microscope COLTRIMS and the ECR ion source. In comparison to earlier designs, the ring lattice was modified in many details: Problems in earlier designs were related with e.g. the detection of light particles and highly charged ions with different charge states. Therefore, the deflectors were redesigned completely, allowing a more flexible positioning of the diagnostics. In this contribution the final design of the storage ring is presented and the layout of all elements given. First results from vacuum measurements in the recently assembled quarter ring section are summarized.

TUPLT043	Status of the Cooler Synchrotron COSY-Juelich	ion, beamloading, damping, betatron	1246
	B. Lorentz, U. Bechstedt, J. Dietrich, R. Eichhorn, R. Gebel, A. Lehrach, R. Maier, D. Prasuhn, A. Schnase, H. Schneider, R. Stassen, H. Stockhorst, R. Tölle FZJ/IKP, Jülich
	The cooler synchrotron COSY accelerates and stores unpolarized and polarized protons and deuterons in the momentum range between 300 MeV/c to 3.65 GeV/c. To provide high quality beams, an Electron Cooler at injection and a Stochastic Cooling System from 1.5 GeV/c up to maximum momentum are available. Vertically polarized proton beams with a polarization of more than 0.80 are delivered to internal and external experimental areas at different momenta. Externally, the maximum momentum is up to date restricted to approximately 3.4 GeV/c by the extraction elements installed in COSY. In 2003 deuteron beams with different combinations of vector and tensor polarization were made available for internal and external experiments. An rf dipole was installed, which is used to induce artificial depolarizing resonances. It can be used for an accurate determination of the momentum of the stored beams. The status of the cooler synchrotron COSY is presented and future plans are discussed.

TUPLT044	Delta-T Procedure for Superconducting Linear Accelerator	linac, ion, beamloading, damping	1249
	A. Bogdanov, R. Maier, Y. Senichev FZJ/IKP, Jülich
	Development of the tune-up procedure for a linear accelerator is the next important stage after the design is complete. Conventional delta-T procedure developed for tuning of a normal-conducting linear accelerator by Crandall allows setting up of accelerating field amplitude and phase in cavity with known phase velocity. However, application of the delta-T procedure to a superconducting linac meets some difficulties. In particular, the synchronous phase velocity in superconducting linac is determined by RF phase shift between cavities, but not by geometrical size of accelerating cells as in normal conducting linac. Additionally, in superconducting linac the smaller phase advance leads to an insensibility of particles at the cavity exit to the variation of the electric field inside the cavity. In the paper we consider the modified delta-T procedure adjusted for superconducting linac. Numerical simulations prove that by proposed technique both tasks of preservation of necessary stable region motion and providing the beam with required final energy can be successfully solved.

TUPLT045	Separatrix Formalism Applied to Linacs Accelerating Particles with Different Charge to Mass Ratio	ion, beamloading, damping, betatron	1252
	A. Bogdanov, R. Maier, Y. Senichev FZJ/IKP, Jülich
	We have developed separatrix formalism for superconducting linear accelerators. This method allows optimizing the quasi-synchronous velocity behavior along a linac. It gives a great advantage in acceleration of particles with different charge to mass ratio. In the article design optimization of structure supposed to accelerate different particles is presented. As an example for numerical simulation superconducting injector COSY is taken.

TUPLT046	Luminosity Considerations for Internal and External Experiments at COSY	ion, beamloading, damping, betatron	1255
	A. Lehrach, U. Bechstedt, J. Dietrich, R. Eichhorn, R. Gebel, B. Lorentz, R. Maier, D. Prasuhn, H. Schneider, R. Stassen, H. Stockhorst, R. Tölle FZJ/IKP, Jülich A. Schnase JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
	The future physics program at the Cooler-Synchrotron COSY in Jülich requires intense beams to provide high luminosities up to 10³²cm^-2s^-1 for internal and external experiments. In 2003 the number of unpolarized protons could significantly be increased up to the theoretical space charge limit of COSY. This was achieved by careful study and adjustment of all subsystems in the accelerator chain of COSY. The intensities for polarized proton beams are at best an order of magnitude lower compared to one for unpolarized beams, depending on the beam current provided the injector cyclotron. Still there is some potential for further enhancement of polarized beam intensities. In this paper, luminosity considerations for polarized and unpolarized beams at COSY are presented taking into account different machine cycles and operation modes for internal and external experimental set-ups.

TUPLT047	First Results of Pulsed Superconducting Half-wave Resonators	ion, beamloading, damping, betatron	1258
	R. Stassen, R. Eichhorn, F.M. Esser, B. Laatsch, R. Maier, G. Schug, R. Tölle FZJ/IKP, Jülich
	A pulsed linac for the cooler synchrotron COSY was projected based on superconductive half-wave resonators (HWRs). The concept of single phased resonators is a great challenge related to the requirement of accelerating protons and deuterons up to a similar energy. A cryomodule, which houses four cavities was designed in Cooperation with FZJ-ZAT, taking into account the restricted space and the special requirements of a linear accelerator. Two prototypes of the 160MHz Half-Wave Resonators (HWRs) were built at different companies. The fabrication differs slightly concerning the top and bottom parts of the cavity as well as the welding of the inner and outer conductor. First results of warm and cold measurements will be presented. The behaviour of the adjustable 4kW main coupler as well as the mechanical tuner can be tested together with the HWR in a new vertical test-cryostat.

TUPLT049	Triple-spoke Cavities in FZJ	ion, beamloading, damping, betatron	1261
	E. Zaplatin, W. Braeutigam, R. Maier, M. Pap, M. Skrobucha, R. Stassen, R. Tölle FZJ/IKP, Jülich
	We report the situation with superconducting triple-spoke cavity activities at the research center FZJ in Juelich. The Nb prototype of the 700 MHz, beta=0.2 cavity is already in fabrication and should be tested this year. This work has been initiated for the European Spallation Source project. In the frames of the new European project of High Intensity Pulsed Proton Injector the 352 MHz, beta=0.48 cavity is under developments. This cavity should be designed, built and tested in the Lab within next few years.

TUPLT050	Lattice for CELLS	emittance, ion, beamloading, damping	1264
	M. Muñoz, D. Einfeld CELLS, Bellaterra (Cerdanyola del Vallès)
	The CELLS is an approved project to build a national synchrotron light source in Spain. The main goals of the project are to provide a medium energy machine (3 GeV) with low emittance and top up operation, a circumference of ~280 m and at least 12 straight sections available for experiments. At present, two lattices are being considered. The first one is based in QBA optics and provides and emittance of 5 nm-rad, using existing technologies. The second one is a TBA one, with an emittance of 2 nm, where physical aperture are reduced by at least a factor 2 and gradients in the bending magnets are up to 10 T/m. We present the selected lattice, and review the main beam dynamics (energy acceptance, errors) issues.

TUPLT051	Beam Optical Design of a Multi Charge Ion Recirculator for Charge Breeders	emittance, beamloading, damping, betatron	1267
	R. Cee, W. Mittig, A.C.C. Villari GANIL, Caen
	Ions of high charge states as required for both stable and radioactive beams in order to optimally profit from the existing accelerating voltage can be produced by means of a charge breeder. However, the energy increase obtained is accompanied by an intensity decrease due to the low efficiency of the charge breeding process. With respect to the production of radioactive beams an enhancement of the breeding efficiency would be most desirable to avoid a high power primary beam as yet inevitable to counteract the loss in intensity. For this purpose the beam optics of an ion recirculation capable to separate the desired charge state and to reinject the remaining charge spectrum has been designed. The ions extracted from both sides of the charge breeder are focused by electrostatic quadrupole doublets and bent by two 180° dipole magnets. After one revolution the optics realises horizontally a (1:1) and vertically a (1:-1) point-to-point image independent from the charge state of the ions. The second order geometric aberrations as well as most of the chromatic aberrations vanish.

TUPLT052	GANIL Status Report	ion, emittance, target, beamloading	1270
	F. Chautard, J.L. Baelde, C. Barue, C. Berthe, A. Colombe, L. David, P. Dolegieviez, B. Jacquot, C. Jamet, P. Leherissier, R. Leroy, M.H. Moscatello, E. Petit, A. Savalle, G. Sénécal, F. Varenne GANIL, Caen
	The GANIL facility (Caen, France) is dedicated to the acceleration of heavy ion beams for nuclear physics, atomic physics, radiobiology and material irradiation. The production of radioactive ion beams for nuclear physics studies represents the main part of the activity. The in-flight fragmentation method was already used, since 1994, with the SISSI device. Since September 2001, SPIRAL, the Radioactive Ion Beam Facility at GANIL, delivers radioactive species produced by the ISOL method. The heavy ion beams of GANIL are sent onto a target and source assembly, and the radioactive beams are accelerated up to a maximum energy of 25 MeV/u by the cyclotron CIME. The operation and the running statistics of GANIL-SPIRAL are presented, with particular attention to the first SPIRAL beams. Few results about the cyclotron CIME, as the mass selection and tuning principle are summarized. The recent developments for increasing stable beams intensities, up to a factor 13 for argon, for use with SPIRAL, SISSI, or the LISE spectrometer, are presented. Considering the future of GANIL, SPIRAL II projects aims to produce high intensity secondary beams, by fission induced with a 5 mA deuteron beam in an uranium target.

TUPLT053	Recent Evolutions in the Design of the French High Intensity Proton Injector (IPHI)	ion, emittance, target, beamloading	1273
	P.-Y. Beauvais CEA/DSM/DAPNIA, Gif-sur-Yvette
	In 1997, the two French National Research Agencies (CEA and CNRS) decided to collaborate in order to study and construct a prototype of the low energy part of a High Power Proton Accelerator (HPPA). The main objective of this project (the IPHI project), is to allow the French team to master the complex technologies used and the control concepts of the HPPAs. Recently, a collaboration agreement was signed with the CERN and led to some evolutions in the design and in the schedule. The IPHI design current was maintained at 100 mA in Continuous Wave mode. This choice should allow to produce a high reliability beam at reduced intensity (typically 30 mA) tending to fulfill the Accelerator Driven System requirements. The output energy of the Radio Frequency Quadrupole (RFQ), originally set to 5 MeV, was reduced to 3 MeV, allowing then the adjunction and the test in pulsed mode of a chopper line developed by the CERN for the Superconducting Proton Linac (SPL). In a final step, the IPHI RFQ and the chopper line should become parts of the SPL injector. In this paper, the IPHI project evolutions are reported as well as the construction and operation schedule.

TUPLT054	Design of the Low-beta, Quarter-wave Resonator and its Cryomodule for the SPIRAL 2 Project	emittance, beamloading, damping, betatron	1276
	P.-E. Bernaudin, P. Bosland, S. Chel, G. Devanz, P. Hardy, F. Michel, P. de Girolamo CEA/DSM/DAPNIA, Gif-sur-Yvette
	The SPIRAL 2 project, to be built in GANIL, consists of a 40 MeV linear accelerator for 5 mA of deuterons and a target-source complex for the production of exotic isotopes. The accelerator is also optimised to accelerate q/A = 1/3 ion up to 14.4 MeV/u. The three stages of the linac are a RFQ (up to 0.75 MeV/A), a low beta (0.007) and a high beta (0.12) sections consisting of quarter-wave, 88 MHz superconducting resonators. This paper focuses on the low beta cavity and its cryomodule. The cavity nominal accelerating gradient is at least 6.5 MV/m in operation conditions. RF properties of the cavities are dealt with, as well as the mechanical ones: helium pressure effects, tunability, vibrations. The cryomodule is designed so as to save longitudinal space and therefore is partly assembled in clean room.

TUPLT056	ECRIS Development for the SPIRAL II Project	beamloading, damping, betatron, cathode	1279
	P. Sortais, J.-C. Curdy, A. Lachaize, T. Lamy, A. Ponton, P. Sole, T. Thuillier, J.-L. Vieux-Rochaz, D. Voulot LPSC, Grenoble
	The SSI/LPSC laboratory is involved in the development of high intensity sources for the driver accelerator and on the improvements of a charge breeding system for its operation inside an highly radioactive environment. We will present the results obtained for the qualification of a 5 mAe/40 KV beam of Deuteron ions dedicated to the feeding of the driver. Concerning the heavy ions, the source PHOENIX 18/28 GHz has been chosen as injector of the driver. The optimization of the source is done in order to produce reliable beams of 1mAe / O⁶⁺ and 0.3 mAe of Ar¹²⁺ at 60 KV. Theses developments are presently done with the room temperature version of PHOENIX (including a new version of the hexapole of the source). In parallel, an upgrade version of PHOENIX, using HTS coils, is under construction and is dedicated to production of very high intensity of the Argon ions (up to 1 mAe of Ar¹²⁺). A charge breeding system is also under qualification. The PHOENIX Booster source confirms that efficiency for mass around hundred can reach up to 6%. Now the efforts consist in precisely defining the 1+ beam matching for charge breeding tuning of the source (emittance measurements).

TUPLT057	Beam Dynamics Studies for the Fault Tolerance Assessment of the PDS-XADS Linac Design	beamloading, damping, betatron, cathode	1282
	J.-L. Biarrotte IPN, Orsay M. Novati, P. Pierini INFN/LASA, Segrate (MI) H. Safa, D. Uriot CEA/DSM/DAPNIA, Gif-sur-Yvette
	In order to meet the high availability/reliability required by the PDS-XADS design the accelerator needs to implement, to the maximum possible extent, a fault tolerance strategy that would allow beam operation in the presence of most of the envisaged faults that could occur in its beamline components. In this work we report the results of beam dynamics simulations performed to characterize the effects of the faults of the main linac components (cavities, deflecting and focusing magnets, …) on the beam parameters. The outcome of this activity is the definition of the possible corrective and preventive actions that could be conceived (and implemented in the system) in order to guarantee the fault tolerance characteristics of the accelerator.

TUPLT058	High Intensity Linac Driver for the SPIRAL-2 Project : Design of Superconducting 88 MHz Quarter Wave Resonators (beta 0.12), Power Couplers and Cryomodules	beamloading, damping, betatron, cathode	1285
	T. Junquera, J.-L. Biarrotte, S. Blivet, S. Bousson, C. Commeaux, G. Olry, H. Saugnac IPN, Orsay P. Balleyguier CEA/DAM, Bruyères-le-Châtel M. Fruneau, Y. Gomez-Martinez, E. Vernay, F. Vezzu LPSC, Grenoble
	A Superconducting Linac Driver, delivering deuterons with energy up to 40 MeV (5 mA) and heavy ions with energy of 14.5 MeV/u (1 mA ), is proposed for the Spiral-2 radioactive beams facility. For the high energy section of the linac, a superconducting 88 MHz Quarter Wave Resonator (beta 0.12) has been designed and the optimisation of RF and mechanical performances will be presented. Based on the present state-of-art of the Superconducting RF technology, maximum electric surface field of 40 MV/m and magnetic surface field of 80 mT, have been adopted which should allow to reach an accelerating field of 7 MV/m (energy gain 3 MeV per resonator). A first complete prototype is under construction. The high intensity deuteron beam specifications have imposed the design of an original power coupler (maximum power 20 KW). The RF, mechanical, and thermal characteristics will be presented. The design of the cryomodule for this high energy section, integrating two QWR with its associated equipments (couplers, tuners, helium tanks), will be presented.

TUPLT059	Evolution of Optical Asymmetries in the Elettra Storage Ring	beamloading, damping, betatron, cathode	1288
	F. Iazzourene, S. Di Mitri, E. Karantzoulis, L. Tosi ELETTRA, Basovizza, Trieste
	Optical asymmetries have been measured and analyzed, before and after the magnet realignments. One way is to compare theoretical to measured orbit response matrices. Another way is to analyze the measured response matrix itself, by comparing the measured effects at identical optical positions. To evaluate the effects of the sextupoles on the optical asymmetries, the measurements have been performed with the sextupoles ON and OFF. The impact of a partial realignment is also analyzed both by varying the quadrupole excitations as well as by performing dispersion and coupling measurements. The results are presented in this paper.

TUPLT060	Production of Radioactive Ion Beams for the EXCYT Facility	ion, target, beamloading, damping	1291
	M. Menna, G. Cuttone, M. Re INFN/LNS, Catania
	The EXCYT facility (EXotics with CYclotron and Tandem) at the INFN-LNS is based on a K-800 Superconducting Cyclotron injecting stable heavy-ion beams (up to 80 MeV/amu, 1 emA) into a target-ion source assembly to produce the required nuclear species, and on a 15 MV Tandem for post-accelerating the radioactive beams. After thermal ANSYS simulations, during May 2003 the Target-Ion Source assembly (TIS) was successfully tested at GANIL under the same operational conditions that will be initially used at EXCYT. Yields and production efficiencies for 8,9Li were compatible with the ones obtained at SPIRAL. Following suggestions by the Referees and the LNS Research Division, we decided to deliver 8Li as the first EXCYT radioactive beam (primary beam 13C). This choice also takes in account the availability of MAGNEX in 2004 as well as the requests and the first results obtained by the Big Bang collaboration. The commissioning of the EXCYT facility is foreseen by the end of 2004 together with the start of nuclear experiments program. In this poster we also report prospective ion beams currently in development.

TUPLT061	Production and Transport of Radioactive Francium for Magneto-optical Trapping	ion, target, beamloading, damping	1294
	G. Stancari, R. Calabrese, B. Mai, G. Stancari, L. Tomassetti INFN-Ferrara, Ferrara S.N. Atutov, V. Guidi UNIFE, Ferrara V. Biancalana, A. Burchianti, A. Khanbekyan, C. Marinelli, E. Mariotti, L. Moi, S. Veronesi UNISI, Siena L. Corradi, A. Dainelli INFN/LNL, Legnaro, Padova P. Minguzzi, S. Sanguinetti UNIPI, Pisa
	An innovative facility for the production and trapping of francium isotopes is operating at the INFN laboratories in Legnaro, Italy. The goal is to obtain a dense cloud of cold and possibly polarized radioactive atoms for a wide range of fundamental studies. Among them are high-resolution laser spectroscopy, alpha-decay asymmetries from deformed nuclei, and tests of the standard model at low transferred momenta. The production of francium is achieved by sending a 100-MeV oxygen-18 beam from the Tandem-XTU accelerator on a thick gold target. The extraction of Fr+ is enhanced by heating the target to 1200 K and by biasing it at +3 kV. The ions are transported to the magneto-optical trap (MOT) through a 7-m electrostatic beam line. The diagnostic systems for monitoring the beam intensity (10⁵ ions/s) are based on silicon detectors sensitive to the alpha particles from Fr decays. Beams of stable Rb+ can also be used for optimizing the transport and trapping processes. Prior to injection into the MOT the beam is neutralized and released in atomic form by a heated yttrium or zirconium foil. Details on the production, transport and neutralization processes are presented.

TUPLT062	Design of the Proton Beam Line for the Trade Experiment	ion, beamloading, damping, betatron	1297
	C. Ronsivalle, L. Picardi ENEA C.R. Frascati, Frascati (Roma) S. Monti, F. Troiani ENEA C.R. Rome, Rome
	The TRADE (Triga Accelerator Driven Experiment)experiment, to be performed in the TRIGA reactor of the ENEA-Casaccia centre consists in the coupling of a 140-300 MeV, 0.5 mA proton beam produced by a cyclotron to a target hosted in the central thimble of the reactor scrammed to sub-criticality. A 30 m long beamline has been designed to transfer the beam injecting it from the top of the pool with special care of having low losses in TRIGA building where a limited shielding of the line is possible. A particular attention was paid to reduce the number and size of elements in the last part of the beamline that are immersed in the pool's water. The paper presents a description of the beam line, the design criteria and the results of beam dynamics calculations.

TUPLT063	Laser Temporal Pulse Shaping Experiment For SPARC Photoinjector	ion, laser, beamloading, damping	1300
	C. Vicario, A. Ghigo INFN/LNF, Frascati (Roma) I. Boscolo, C. Vozzi Universita' degli Studi di Milano, MILANO S. Cialdi, A.F. Flacco INFN-Milano, Milano M. Nisoli, G. Sansone, S. Stagira Politecnico/Milano, Milano M. Petrarca INFN-Roma, Roma
	Laser for driving high brightness photoinjector have to produce UV square pulse which is predicted to be the optimum profile for emittance compensation in advanced photoinjectors. The longitudinal laser pulse distribution, according to numerical simulations for the SPARC photoinjector, must be square with rise and fall time shorter than 1 ps and flat top variable up to 10 ps FWHM. In this paper we report the results of pulse shaping obtained using an acousto-optic (AO) programmable dispersive filter (DAZZLER). The DAZZLER was used to perform spectral amplitude and phase modulation of the incoming 100 fs Ti:Sapphire pulses. Because of the finite length of the crystal the maximum duration of the shaped pulse is 6 ps. To overcome this limitation we used a configuration in which the laser pulses passed twice through the AO filter. A dispersive glass section was also used to lengthen the pulse with a single pass in the DAZZLER. In this paper we report the experimental setup, hardware description and time and frequency domain measurements.

TUPLT065	Beams from RF Ovens and ECR Ion Sources	injection, laser, beamloading, damping	1303
	M. Cavenago INFN/LNL, Legnaro, Padova T. Kulevoy, S. Petrenko ITEP, Moscow
	Beam of silver, copper and recently platinum were produced with the radiofrequency oven technique. The ECRIS (Electron Cyclotron Resonance Ion Source) can be conveniently considered as a charge breeder for any injection device; this approach allows to compare the injection of metals from ovens with other techniques discussed in the literature, like the injection from mevva (Metal Vapor Vacuum Arc) sources or the injection of single charged RIB (radioactive ion beams) or the simple injection of heavy gas. Extensive experiments extracting beams of copper (charge up 13+) or silver (charge up to 19+) or xenon (charge up 20+) with the same ECRIS condition are described, and advantage of rf oven over gas injection are discussed; in particular the oven crucible can be easily voltage biased up to -400 V, to modify ECRIS plasma shape. Heating the tantalum crucibles over 2300 K (average temperature) requires careful axial alignment to avoid the formation of hot spots; preliminary evidence of this effect and its numerical modeling are also described.

TUPLT066	Study of a High-current 176 MHz RFQ as a Deuteron Injector for the SPES Project	injection, laser, beamloading, damping	1306
	M. Marchetto, M. Comunian, E. Fagotti, A. Palmieri, A. Pisent INFN/LNL, Legnaro, Padova
	The SPES project, aimed at the construction of a RIB facility at LNL, is initially based on the use of a primary proton beam, but it foresees a future development based on the usage of deuterons and light ions. In this article we report about the preliminary study of a 176 MHz RFQ to be used as an injector for such kind of beams. The structure explored foresees a ?four ladder? symmetric resonator, built in brazed copper. In particular beam dynamics, electrodynamics design and preliminary thermo-structural analysis of the cavity is presented.

TUPLT069	Approaching to a Mono-modal Accelerating Cavity based on Photonic Band-gap Concepts	injection, laser, beamloading, damping	1309
	M.R. Masullo INFN-Napoli, Napoli A. Andreone, E. Di Gennaro, G. Lamura Naples University Federico II, Napoli F. Francomacaro, M. Panniello, V.G. Vaccaro Naples University Federico II and INFN, Napoli G. Keppel, V. Palmieri, D. Tonini INFN/LNL, Legnaro, Padova
	One of the main problem of high intensity accelerators is the presence of high order modes (HOMs) which might degrade the beam quality. Accelerating cavities require HOMs suppression while keeping high quality factor (Q) fundamental mode. Both these requirements can be hardly met in closed metallic cavities. In low frequency cases and for particular geometries it is possible to partially suppress HOMs, but at high frequencies and for superconducting cavities configuration becomes cumbersome and technically unviable. We propose here a high Q cavity based on Photonic Band Gap (PBG) concepts, operating in the microwave region. The cavity consists of a two-dimensional lattice, where posts (dielectric, metallic or superconducting) are sandwiched by two conducting plates. This sandwich exhibits two kinds of frequency bands: 'pass-bands' and 'stop-bands'. It is possible to localize modes in an equivalent cavity obtained by removing posts. These modes are localized in the 'cavity'. In this way, one can obtain a quasi-mono-modal cavity: high Q fundamental mode and HOMs falling into the pass bands. We will present the study, the optimisation and the measurements of our metallic (Copper) PBG structure working in the 2-20 GHz range. The development of a different cryogenic set-up, necessary to characterise an all superconducting or an hybrid (dielectric/metallic) structure, is under way.

TUPLT070	Study of a Linac Booster for Proton Therapy in the 30-62 MeV Energy Range	injection, linac, laser, beamloading	1312
	V.G. Vaccaro, A. D'Elia, M.R. Masullo Naples University Federico II and INFN, Napoli D. Capasso, S. Lanzone Naples University Federico II, Napoli T. Clauser, A. Rainò INFN-Bari, Bari C. De Martinis, D. Giove, M. Mauri INFN/LASA, Segrate (MI) V. Variale Bari University, Science Faculty, Bari
	Recent results in accelerator physics have shown the feasibility of a coupling scheme between a cyclotron and a linac for proton acceleration. Cyclotrons with energies up to 30 MeV, mainly devoted to radioisotopes production, are available in a large number of medical centres. These two evidences have suggested the idea to study and design a linac booster able to increase the initial proton energy up to the values required for the treatment of tumors, like the ocular ones. The main challenge in such a project is related to meet the requirements arising from the beam dynamics with the constrains due both to the mechanical structures and tolerances and to the heat dissipation mechanism chosen in the design. In this paper we will review the rationale of the project and we will discuss the basic design of a compact 3 Ghz linac with a new approach to the cavities used in a SCL (Side Coupled Linac) structure

TUPLT071	A 5 MeV Electron Linac for Radiation Processing	injection, laser, beamloading, damping	1315
	A. Trifirò, L. Auditore, R.C. Barnà, D. De Pasquale, A. Italiano, M. Trimarchi INFN - Gruppo Messina, S. Agata, Messina
	In recent years, radiation processing is rapidly growing in various field of industrial treatments and scientific research as a safe, reliable and economic technique. To match the requirements of several applications, a 5 MeV, 1 kW electron linac has been developed at the Dipartimento di Fisica (Università di Messina), in collaboration with the ENEA Accelerators Group (Frascati- Rome). This self- containing standing wave accelerator, driven by a 3 GHz, 2.5 MW Magnetron, has been designed, by means of the SUPERFISH and PARMELA codes, in such a way as to obtain an autofocusing structure, that will be used to develop a transportable system for 'in-situ' industrial radiography and X-ray digital tomography. For this accelerator, compact pulse forming circuits have been properly developed for the magnetron and the cathode, and pulse frequency can be varied ranging from 1 to 300 Hz, thus allowing the study of several applications of radiation processing. Main features of the accelerating structure, as well as beam spot dimensions, surface dose distribution and electron beam energy range will be described.

TUPLT072	Dual Harmonic Acceleration with Broadband MA Cavities in J-PARC RCS	injection, laser, beamloading, damping	1318
	M. Yamamoto JAERI, Chiba-ken S. Anami, E. Ezura, K. Hara, Y. Hashimoto, C. Ohmori, A. Takagi, M. Yoshii KEK, Ibaraki M. Nomura, A. Schnase, F. Tamura JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
	In the J-PARC RCS rf system, since the fundamental rf acceleration voltage and the 2nd higher harmonic one are applied to each cavity, the impedance of hte cavity has a broadband characteristic. The Q-value of the cavity is chosen to make the higher harmonic beam loading effect as small as possible. The analysis of the amplifier and the beam loading effect on the dual harmonic rf system is described.

TUPLT073	Observation of Coupling Resonance in HIMAC Synchrotron	injection, laser, beamloading, damping	1321
	T. Uesugi, T. Fujisawa, K. Noda, S. Shibuya, D. Tann, H. Uchiyama NIRS, Chiba-shi Y. Hashimoto KEK, Ibaraki I.N. Meshkov, E. Syresin JINR, Dubna, Moscow Region
	Coupling resonance was observed at operating points near to Qx-Qy=1. Two-dimensional profile of a beam at its equilibrium was measured, and it was found that the beam was inclined in transverse when the operating point is near to the resonance condition. We will present the detail of the measurement and the results.

TUPLT074	Dark Current Reduction System for SPring-8 Linac	injection, linac, laser, beamloading	1324
	T. Kobayashi, T. Asaka, H. Hanaki, M. Shoji, S. Suzuki, K. Tamura JASRI/SPring-8, Hyogo
	The SPring-8 linac accelerates dark currents generated by its injector part up to 1 GeV. These dark currents are injected with main beam into the SPring-8 storage ring and then spoil the purity of the stored beam. The dark currents are mainly composed of a grid emission current from a thermionic gun and field emission currents from rf accelerating structures. A beam deflector for kicking only the grid emission by a pulsed electric field was developed and installed in the SPring-8 linac. We observed that the beam deflector greatly reduced the grid emission current accelerated up to 1 GeV. The measured purity of the stored single-bunched beam was about 5x10^-6 when the deflector operated, which was almost 1/100 of the purity without filtering by the deflector. However, the deflector, which is installed before the prebucher, cannot reduced the field emission currents from the buncher cavities and the first acccelerating structure. These dark currents take considerable proportion of the total dark currents observed at the end of the linac. We are trying to spin off the field emission currents by weak magnetic fields across the accelerating structure generated by several coils.

TUPLT075	Improvements of SPring-8 Linac towards Top-up Operation	booster, laser, synchrotron, beamloading	1327
	S. Suzuki, T. Asaka, H. Dewa, H. Hanaki, T. Kobayashi, T. Masuda, A. Mizuno, T. Taniuchi, H. Tomizawa, K. Yanagida JASRI/SPring-8, Hyogo
	The top-up operation of the SPring-8 storage ring will start in May, 2004. In order to realize alternative injection into the booster synchrotron in the top-up operation and the NewSUBARU, an AC bending magnet replaced the DC bending magnet in the beam transport line to the booster synchrotron. This magnet operates at 1 Hz with a trapezoid current pattern. The 1-GeV electron beam goes at the bottom of the current pattern to the NewSUBARU or at the top of the pattern to the booster synchrotron. In order to obtain the higher reliability of the linac for the top-up operation, reinforcement of the beam monitor systems, further improvement of RF phase stability and upgrade of the control system were required. BPM?s has been newly installed in energy dispersion sections, and beam transport feedback control is in development. The phase variation in the RF system was reduced by the regulation of the gas pressure in the waveguide of the klystrons drive system. We re-engineered the VME systems to maximize availability of the linac operation considering its reliability, usability, expandability and flexibility.

TUPLT145	Transverse Coupling Measurement using SVD Modes from Beam Histories	target, bunching, injection, beamloading	1470
	C.-X. Wang ANL, Argonne, Illinois R. Calaga BNL, Upton, Long Island, New York
	In this report we investigate the measurement of local transverse coupling from turn-by-turn data measured at a large number of beam position monitors. We focus on a direct measurement of coupled lattice functions using the Singular Value Decomposition (SVD) modes and explore the accuracy of this method. The advantages and shortcomings of this model-independent method for coupling measurement will be also discussed.

TUPLT146	Techniques to Extract Physical Modes in Model-independent Analysis of Rings	target, bunching, injection, beamloading	1473
	C.-X. Wang ANL, Argonne, Illinois
	SVD mode analysis is a basic techinique in Model-Independent Analysis of beam dynamics. It decomposes the spatial-temporal variation of a beam centroid into a small set of orthogonal modes based on statistical analysis. Although such modes have been proven to be rather informative, each orthogonal mode may not correspond to an individual physical source but a mix of several in order to be orthogonal. Such mixing makes it difficult to quantitatively understand the SVD modes and thus limits their usefulness. Here we report a new techinique to untangle the mixed modes in storage ring analysis based on the fact that most of the physical modes in a ring have identifiable characteristics in frequency domain.

TUPLT147	Multiple-charge-state Beam Steering in High-intensity Heavy-ion Linacs	target, bunching, injection, beamloading	1476
	E.S. Lessner, P.N. Ostroumov ANL/Phys, Argonne, Illinois
	An algorithm suitable for correction to steering of multiple-charge-state beams in heavy-ion linacs operating at high currents has been developed []. It follows a four-dimensional minimization procedure that includes coupling of the transverse beam motions. A major requirement is that it obeys the restricted lattice design imposed by the acceleration of multiple-charge-state heavy-ion beams []. We study the algorithm efficiency in controlling the beam effective emittance growth in the presence of random misalignments of cavities and focusing elements. Limits on misalignments are determined by quantifying beam losses and effective steering requirements are selected by examining several correcting schemes within the real-state constraints. The algorithm is used to perform statistically significant simulations to study beam losses under realistic steering. E. S. Lessner and P. N. Ostroumov, Proc. Part. Accel. Conf. (2003)** P. N. Ostroumov, Phys. Rev. STAB Vol. 5, 0030101 (2002)

TUPLT149	Beam Manipulation and Compression Using Broadband RF Systems in the Fermilab Main Injector and Recycler	target, bunching, injection, beamloading	1479
	G.W. Foster, C.M. Bhat, B. Chase, J.A. Mac Lachlan, K. Seiya, P. Varghese, D. Wildman Fermilab, Batavia, Illinois
	Successful tests of new method for beam manipulation, compression, and stacking using the broadband RF systems in the Fermilab Recycler and Main Injector are described. Under usual conditions an unbunched beam can be confined to a fraction of the azimuth of the ring by a set of "Barrier Pulses" which repel particles trying to escape from the ends of the segment of beam. One way to compress or expand the azimuthal extent of the segment of beam is to slowly change the distance between barrier pulses. However when it is desired to rapidly compress or expand the length of the segment, a linear ramp can be superimposed on the waveform between barrier pulses. This causes particles at the front and back of the beam segment to be accelerated or decelerated by differing amounts, and the velocity correlation along the length of the beam segment causes it to expand or contract. When the expansion or contraction is halfway completed, the ramp voltage is reversed so the all particles will come relatively to rest at the end of the process. With the Barrier pulses following appropriately, no particles leak out the ends of the beam segment and the emittance is preserved.

TUPLT150	Vector Sum Control of an 8 GeV Superconducting Proton Linac	target, bunching, injection, beamloading	1482
	M. Huening, G.W. Foster Fermilab, Batavia, Illinois
	Fermilab is investigating the feasibility of an economical 8 GeV superconducting linac for H-. In order to reduce the construction costs it is considered to fan out the rf power to a string of accelerating structures per klystron. Below 1 GeV the individual fluctuations of the cavities will be compensated by high power phase shifters, above 1 GeV the longitudinal dynamics are sufficiently damped to consider omitting the phaseshifters. The impact of this setup on the field stability of individual cavities and ultimately the beam energy has been studied.

TUPLT154	Aperture Studies for the Fermilab AP2 Anti-proton Line	electron, bunching, injection, beamloading	1491
	I. Reichel, M. Placidi, M.S. Zisman LBNL, Berkeley, California K. Gollwitzer, S. Werkema Fermilab, Batavia, Illinois
	The AP2 beamline transports anti-protons from the production target to the Debuncher ring. In the past the observed aperture has been smaller than that estimated from linear, on-energy optics. We have investigated possible reasons for the aperture limitation and have identified possible sources, including residual vertical dispersion from alignment errors and chromatic effects due to very large chromatic lattice functions. Some experiments have already been performed to study these effects. We present results of the experimental and theoretical studies and possible remedies.

TUPLT159	First Commissioning Experiments at DARHT-II	focusing, bunching, injection, beamloading	1497
	C. Ekdahl, E.O. Abeyta, L. Caudill, K.C.D. Chan, D. Dalmas, S. Eversole, R.J. Gallegos, J. Harrison, M. Holzscheiter, E. Jacquez, J. Johnson, B.T. McCuistian, N. Montoya, K. Nielsen, D. Oro, L. Rodriguez, P. Rodriguez, M. Sanchez, M. Schauer, D. Simmons, H.V. Smith, J. Studebaker, G. Sullivan, C. Swinney, R. Temple LANL, Los Alamos, New Mexico H. Bender, W. Broste, C. Carlson, G. Durtschi, D. Frayer, D. Johnson, K. Jones, A. Meidinger, K. Moy, R. Sturgess, C.-Y. Tom Bechtel Nevada, Los Alamos, New Mexico Y.-J. Chen, T. Houck LLNL, Livermore, California S. Eylon, W. Fawley, E. Henestroza, S. Yu LBNL, Berkeley, California T. Hughes, C. Mostrom Mission Research Corporation, Albuquerque, New Mexico
	The second axis of the Dual Axis Radiographic Hydro-Test (DARHT) facility will provide up to four short(< 150 ns) radiation pulses for flash radiography of high-explosive driven implosion experiments[1]. The DARHT-II linear induction accelerator (LIA) will produce a 2-kA,18-MeV,2-micro-s electron beam. A fast kicker will cleave four short pulses out of the beam, which will focused onto a tantalum target for conversion to bremsstrahlung pulses for radiography. The first tests of the second axis accelerator were designed to demonstrate the technology, and to meet the modest performance requirements for closing out the DARHT-II construction project. These experiments demonstrated that we could indeed produce a 1.2 kA beam with pulse length 0.5-1.2 s and accelerate it to 12.5 MeV. These de-rated parameters were chosen to minimize risk of damage in these first experiments with this novel accelerator. The beam was stable to the BBU instability for these parameters. In fact, we had to reduce the magnetic guide field by a factor of 5 before any evidence of BBU was observed. We will discuss the results of these experiments and their implications, as well as our plans for continuing with DARHT-II commissioning.

TUPLT170	The SNS Beam Power Upgrade	focusing, bunching, betatron, beamloading	1527
	S. Henderson, S. Assadi, R. Cutler, V.V. Danilov, G.W. Dodson, R.E. Fuja, J. Galambos, J.A. Holmes, N. Holtkamp, D.-O. Jeon, S. Kim, L.V. Kravchuk, M.P. McCarthy, G.R. Murdoch, D.K. Olsen, T.J. Shea, M.P. Stockli ORNL/SNS, Oak Ridge, Tennessee
	The Spallation Neutron Source (SNS) accelerator systems, which consist of an H^- injector, a 1 GeV linear accelerator, an accumulator ring and associated transport lines, will provide a 1 GeV, 1.44 MW proton beam to a liquid mercury target for neutron production. The SNS is presently under construction at Oak Ridge National Laboratory and will begin operations in 2006. Even in the baseline design, many of the accelerator subsystems are capable of supporting higher beam intensities and higher beam energy. We report on upgrade scenarios for the SNS accelerator systems which increase the 1.44 MW baseline beam power to at least 3 MW, and perhaps as high as 5 MW. The increased SNS beam power can be achieved primarily by increasing the H^- ion source current, installing additional superconducting cryomodules to increase the final linac beam energy to 1.3-1.4 GeV, and modifying injection and extraction hardware in the ring to handle the increased beam energy. The upgrade beam parameters will be presented, the required hardware modifications will be described, and the beam dynamics implications will be discussed.

TUPLT171	ORBIT Simulations of the SNS Accumulator Ring	focusing, bunching, betatron, beamloading	1530
	J.A. Holmes, S.C. Bunch, S.M. Cousineau, V.V. Danilov, S. Henderson, A. Shishlo ORNL/SNS, Oak Ridge, Tennessee M. Plum LANL, Los Alamos, New Mexico Y. Sato IUCF, Bloomington, Indiana
	As SNS undergoes construction, many detailed questions arise concerning strategies for commissioning and operating the accumulator ring. The ORBIT Code is proving to be an indispensible tool for addressing these questions and for providing guidance to the physicists and decision makers as operation draws near. This paper shows the application of ORBIT to a number of ring issues including exclusion of the HEBT RF cavities during commissioning, the detailed effect of the injection chicane magnets on the beam, the effects and correction of magnet alignment and multipole errors, debunching of the linac 402.5 MHz beam structure, the injection of self consistent uniform beam configurations, and initial electron cloud simulations.

TUPLT181	Results of the First Run of the NASA Space Radiation Laboratory at BNL	focusing, bunching, betatron, beamloading	1550
	K.A. Brown, L. Ahrens, J.M. Brennan, J. DeLong, C. Gardner, D. Gassner, J. Glenn, Y. Kotlyar, I. Marneris, A. Rusek, N. Tsoupas, K. Zeno BNL, Upton, Long Island, New York
	The NASA Space Radiation Laboratory (NSRL) was constructed in collaboration with NASA for the purpose of performing radiation effect studies for the NASA space program. The results of commissioning of this new facility were reported in []. In this report we will describe the results of the first run. The NSRL makes use of heavy ions in the range of 0.05 to 3 GeV/n slow extracted from BNL's AGS Booster. Many modes of operation were explored during the first run, demonstrating all the capabilities designed into the system. Heavy ion intensities from 100 particles per pulse up to 2×10⁹ particles per pulse were delivered to a large variety of experiments, providing a dose range up to 70 G/min over a 5x5 cm² area. Results presented will include those related to the production of beams that are highly uniform in both the transverse and longitudinal planes of motion []. K.A.Brown, et al, ‘‘Commissioning Results of Slow Extraction of Heavy Ions from the AGS Booster‘‘, Proceedings of the 2003 Particle Accelerator Conference, Portland, OR, 2003** N.Tsoupas, et al, ‘‘Commissioning of the Beam Transfer Line of the Booster Application Facility (BAF) at BNL'', These Proceedings

TUPLT182	Measuring Local Gradient and Skew Quadrupole Errors in RHIC IRs	focusing, bunching, betatron, beamloading	1553
	J.F. Cardona UNAL, Bogota D.C S. Peggs, F.C. Pilat, V. Ptitsyn BNL, Upton, Long Island, New York
	The measurement of local linear errors at RHIC interaction regions using an "action and phase" analysis of difference orbits has already been presented []. This paper evaluates the accuracy of this technique using difference orbits that were taken when known gradient errors and skew quadrupole errors were intentionally introduced. It also presents action and phase analysis of simulated orbits when controlled errors are intentionally placed in a RHIC simulation model. J. Cardona, S. Peggs, T. Satogata, F. Pilat and V. Ptitsyn,"Determination of Linear and Non Linear Components in RHIC Interaction Regions from difference Orbit Measurements", EPAC 2002, Paris, 2002, p.311-313.

TUPLT183	Magnetized Beam Transport in Electron Coolers with Opposing Solenoid Fields	focusing, electron, bunching, beamloading	1556
	J. Kewisch, C. Montag BNL, Upton, Long Island, New York
	To improve cooling capability of electron coolers magnetized beams in strong solenoid fields are used. Too avoid betatron coupling in the ion coupling compensation is required. For the RHIC electron cooler we propose a scheme consisting of two identical solenoids with opposing fields, connected by a quadrupole matching section that preserves the electron beam magnetization. Since the fringe fields of the individual magnets overlap, the matching section can not be designed with standard optics codes. We developed an optimization code based on particle tracking instead. Input for the program are the simulated/measured field maps of the magnets. We demonstrate that the transverse temperature of the electron beam does not increase.

TUPLT185	Principle of Skew Quadrupole Modulation to Measure Betatron Coupling	focusing, electron, bunching, beamloading	1562
	Y. Luo, F.C. Pilat, T. Roser, D. Trbojevic, J. Wei BNL, Upton, Long Island, New York
	The idea of modulating Skew Qudrupoles to measure the ring betatron coupling was put forth by T. Roser. In this paper, analytical solutions for this technique is given. Simulation are also carried out based on RHIC. And other relevent issues concerning this technique's application are also discussed. All of them show this idea of modulating skew qudrupoles to measure the betatron coupling are applicable.

TUPLT186	Managing System Parameters for SNS Magnets and Power Supplies	focusing, electron, bunching, beamloading	1565
	W.J. McGahern, S. Badea, F.M. Hemmer, H.-C. Hseuh, J.W. Jackson, A.K. Jain, F.X. Karl, R.F. Lambiase, Y.Y. Lee, C.J. Liaw, H. Ludewig, G.J. Mahler, W. Meng, C. Pai, C. Pearson, J. Rank, D. Raparia, J. Sandberg, S. Tepikian, N. Tsoupas, J. Tuozzolo, P. Wanderer, J. Wei, W.-T. Weng BNL, Upton, Long Island, New York R. Cutler, J.J. Error, J. Galambos, M.P. Hechler, S. Henderson, P.S. Hokik, T. Hunter, G.R. Murdoch, K. Rust, J.P. Schubert ORNL/SNS, Oak Ridge, Tennessee
	The Spallation Neutron Source (SNS), currently under construction at Oak Ridge, Tennessee, is a collaborative effort of six U.S. Department of Energy partner laboratories. With over 312 magnets and 251 power supplies that comprise the beam transport lines and the accumulator ring, it is a challenge to maintain a closed loop on the variable parameters that are integral to these two major systems. This paper addresses the input variables, responsibilities and design parameters used to define the SNS magnet and power supply systems.

TUPLT187	SNS Extraction Kicker Power Supply Control	focusing, electron, bunching, beamloading	1568
	J.-L. Mi, L. Hoff, R.F. Lambiase, Y.Y. Lee, J. Sandberg, Y. Tan, N. Tsoupas, R. Zapasek, W. Zhang BNL, Upton, Long Island, New York
	There are fourteen PFN power supplies, which will be installed in the SNS Extraction Kicker System. This paper will introduce these fourteen-power supplies arrangement and control schematic. These control instruments and boards are installed into four standard racks. Some of the control boards functions will be list in this paper. Control racks and some control boards pictures will be shown in this paper.

WEOACH02	Gas Condensates onto a LHC Type Cryogenic Vacuum System Subjected to Electron Cloud	focusing, kicker, bunching, beamloading	126
	V. Baglin, B.J. Jenninger CERN, Geneva
	In the Large Hadron Collider (LHC), the gas desorbed via photon stimulated molecular desorption or electron stimulated molecular desorption will be physisorbed onto the beam screen held between 5 and 20 K. Studies of the effects of the electron cloud onto a LHC type cryogenic vacuum chamber have been performed with the cold bore experiment (COLDEX) installed in the CERN Super Proton Synchrotron (SPS). Experiments performed with gas condensates such as H2, H2O, CO and CO2 are described. Implications to the LHC design and operation are discussed.
	Video of talk
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WEOACH03	Achievement of 35 MV/m in the TESLA Superconducting Cavities Using Electropolishing as a Surface Treatment	focusing, kicker, bunching, beamloading	129
	L. Lilje DESY, Hamburg
	The Tera Electronvolt Superconducting Linear Accelerator TESLA is the only linear electron-positron collider project based on superconductor technology for particle accelaration. In the first stage with 500 GeV center-of-mass energy an accelerating field of 23.4MV/m is needed in the superconducting niobium cavities which are operated at a temperature of 2 K and a quality factor Q0 of 10¹⁰. This performance has been reliably achieved in the cavities of the TESLA Test Facility (TTF) accelerator. The upgrade of TESLA to 800 GeV requires accelerating gradients of 35 MV/m. Using an improved cavity treatment by electrolytic polishing it has been possible to raise the gradient to 35 - 43 MV/m in single cell resonators. Here we report on the successful transfer of the electropolishing technique to multi-cell cavities. Presently four nine-cell cavities have achieved 35 MV/m at Q_0 = 5 × 10⁹, and a fifth cavity could be excited to 39 MV/m. In two high-power tests it could be verified that EP-cavities preserve their excellent performance after welding into the helium cryostat and assembly of the high-power coupler. One cavity has been operated for 1100 hours at the TESLA-800 gradient of 35 MV/m and 57 hours at 36 MV/m without loss in performance.
	Video of talk
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WEYCH01	Fast Pulsed SC Magnets	focusing, kicker, bunching, beamloading	132
	G. Moritz GSI, Darmstadt
	The demand for high beam intensities leads to the requirement of fast pulsed magnets for synchrotrons. An example is the proposed 'International Facility for Beams of Ions and Antiprotons' at GSI, which will consist of two synchrotrons in one tunnel and several storage rings. The high field ramp rate and repetition frequency introduce many magnet design problems and constraints in the operation of the accelerator. Persistent currents in the superconductor and eddy currents in wire, cable, iron and vacuum chamber reduce the field quality and generate cryogenic losses. Due to the large number of magnet cycles during the lifetime of such a magnet, special attention has to be paid to magnet material fatigue problems. The large charging voltages put some constraints on the use of cold diodes for quench protection. R&D has started at GSI, in collaboration with many institutions, to comply with the constraints mentioned above. Model dipoles were built and tested. The results of the R&D are reported. The advantages of the use of low field, fast pulsed superconducting, compared to resistive, magnets will be discussed
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WEYCH02	Technical Issues for Large Accelerators based on High Gradient SC Cavities	focusing, kicker, bunching, beamloading	137
	C. Pagani, C. Pagani DESY, Hamburg
	The perspective to build large accelerators based on high gradient superconducting cavities is posing a number of new problems that have been addressed in the preparation of the TESLA project. Starting from the experience gained with the past large installations, such as LEP2 at CERN and CEBAF at JLab, in this paper I discuss the new demands and the solution envisaged. Industrial production issues are focussed in terms of large scale production, reviewed quality control criteria and cost reduction. The impact on component design and engineering together with the expected improvements in term of performances and reliability are also outlined.
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WEYCH03	Low and Medium Beta Superconducting Cavities	focusing, kicker, bunching, beamloading	142
	A. Facco INFN/LNL, Legnaro, Padova
	The use of low- and intermediate-beta superconducting cavities, once confined to low current heavy ion linacs, is steadily increasing in accelerators. The progress in this technology allowed a significant increase in cavity performance during the last 10 years; a large number of resonators, with different geometries, frequencies and gap numbers have been built for a large variety of applications and the development is still going on. The main boost is given by new projects of radioactive beam facilities and high power proton accelerators worldwide. While the advantages of SC resonators, compared with normal conducting structures, are rather well established in high-beta linacs, this is not always the case at low-beta. The choice of the optimum transition beam energy in a linac, where superconducting cavities should replace the room temperature ones, requires a careful evaluation that depends on the linac specifications.
	Video of talk
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WEPKF033	Application of Finite Volume Integral Approach to Computing of 3D Magnetic Fields Created by Distributed Iron-dominated Electromagnet Structures	vacuum, kicker, bunching, beamloading	1675
	O.V. Chubar, C. Benabderrahmane, O. Marcouillé, F. Marteau SOLEIL, Gif-sur-Yvette J. Chavanne, P. Elleaume ESRF, Grenoble
	Iron-dominated electromagnet structures are traditionally considered as a domain of applications of the Finite-Element Method (FEM). FEM computer codes provide high accuracy for "close circuit" type geometries, however they are much less efficient for distributed geometries consisting of many spatially separated magnets interacting with each other. Examples of such geometries related to particle accelerators are insertion devices, quadrupole and sextupole magnets located close to each other, magnets with combined functions. Application of the finite volume integral approach implemented in the Radia 3D magnetostatics code to solving such geometries is described. In this approach, space around individual magnets does not require any meshing. An adaptive segmentation of iron parts, with the segmenting planes being roughly perpendicular or parallel to the expected directions of magnetic flux lines, minimizes dramatically the necessary CPU and memory resources. If a geometry is, nevertheless, too big for its complete interaction matrix to fit into memory, a special scheme of relaxation "by parts" can be applied. The results of calculations made for the SOLEIL electromagnet undulator HU256 will be presented.

WEPKF034	The Modified DAFNE Wigglers	vacuum, kicker, bunching, beamloading	1678
	S. Guiducci, S. Bertolucci, M. Incurvati, M.A. Preger, P. Raimondi, C. Sanelli, F. Sgamma INFN/LNF, Frascati (Roma)
	Modifications to the pole shape of a spare wiggler have been tested to increase the width of the good field region, with the aim of reducing the effect of nonlinearities affecting the dynamic aperture and the beam-beam interaction. Additional plates realized with the same material of the pole have been machined in several shapes and glued on the poles. Accurate measurements of the vertical field component on the horizontal symmetry plane of the magnet have been performed to find the best profile. The particle motion inside the measured field has been simulated to minimize the field integral on the trajectory, to determine the wiggler transfer matrix and to estimate the amount of non linear contributions. All wigglers in the collider have been modified to the optimized pole shape. Measurements with beam performed with the modified wigglers show a significant reduction of nonlinearities.

WEPKF035	Analysis of the Cold Mass Displacements at the TTF	vacuum, kicker, bunching, beamloading	1681
	A. Bosotti, C. Pagani, P. Pierini INFN/LASA, Segrate (MI) R. De Monte, M. Ferianis ELETTRA, Basovizza, Trieste R. Lange DESY, Hamburg
	Few of the TTF cryomodules have been equipped with wire position monitors (WPM) in order to monitor on line the displacements of the cold mass to verify alignment stability and reproducibility . Based on the operation experience of the first prototypical cryomodules, equipped with up to 36 WPMs distributed in two strings, on the last generation cryomodules a single string of 7 sensors has been installed. Here we review and analyze the data collected so far to prove that the the proposed cryomodule design is consistent with the TESLA alignment requirements.

WEPKF037	Structural Analysis of an Integrated Model of Short Straight Section, Service Module, Jumper Connection and Magnet Interconnects for the Large Hadron Collider	kicker, bunching, beamloading, damping	1684
	S. Dutta, J. Dwivedi, A. Kumar, H.C. Soni CAT, Indore (M.P.) B. Skoczen CERN, Geneva
	The Short Straight Section (SSS) of the Large Hadron Collider (LHC) houses a twin quadrupole.The cryogens are fed to the SSS through a Jumper Connection between service modules of Cryogenic Distribution Line (QRL) and SSS.A Finite Element analysis has been performed in collaboration with CERN for the unified model of SSS of LHC,consisting of cold mass, cold supports,vacuum vessel and its bellows, interconnects, jumper connection and alignment jacks. The model has been developed to understand coupling between the quadrupole magnet and the service module due to ground motion and during the realignment or global smoothening of the LHC arc. The model incorporates experimental stiffness values for support posts, internal pipes and jacks and calculated stiffness for magnet-to-magnet interconnects. The computation space and time has been reduced by executing a two step linear static analycal approach with an initial trial analytical approach cycle in which the program estimates the behavior of the flexibles. A special routine is developed within ANSYS,using APDL which selects the correct secant stiffness of flexibles(by applying a user interactive logical algorithm)from their non-linear force displacement characteristics.

WEPKF038	The Alignment Jacks of the LHC Cryomagnets	alignment, kicker, bunching, beamloading	1687
	J. Dwivedi, S.G. Goswami, A. Kumar, V. Madhumurthy, H.C. Soni CAT, Indore (M.P.) V. Parma CERN, Geneva
	The precise alignment of the some 1700 cryomagnets of the LHC collider, requires the use of some 7000 jacks. The specific requirements and the need for an cost-effective solution for this large production, justified the development and industrialisation of a dedicated mechanical jack which was developed, and is now being produced, in the framework of a collaboration between CERN and the Center for Advanced Technology in India. Three jacks support each of the 32-ton heavy, 15-meter long cryo-dipoles of LHC, and provide the required alignment features. The main requirements are a setting resolution of 0.05 mm, and a range of movement of 20 mm in the horizontal and 40 mm in the vertical direction. Each jack has two degrees of controlled movement in the horizontal and vertical direction, whereas the remaining horizontal movement is left free. By a suitable choice of the layout of the three jacks, the full range of alignment of a cryo-magnet can be obtained. The design of the jacks evolved from a preliminary value analysis between various concepts, towards the complete engineering of the retained concept, selection of the most appropriate and cost-effective industrial production processes and setting-up of an effective quality assurance policy. Building and testing of 36 prototype jacks allowed an extensive experimental validation of their performance at CERN, where they were operated in the String 2 facility, and yielded an improved understanding for cost-effective steering of the production processes before launching the series production. Presently, the mass production of the jacks is in progress with two Indian manufacturers, and some 1500 jacks have already been delivered to CERN. Considering the successful performance of the jacks, it is now envisaged to extend the use of the same type of jacks to provide the even higher-demanding alignment of the low-beta quadrupoles of LHC.

WEPKF039	The Vacuum System of Super SOR	alignment, kicker, bunching, beamloading	1690
	H. Sakai, M. Fujisawa, A. Kakizaki, T. Kinishita, H. Kudo, N. Nakamura, O. Okuda, S. Shibuya, K. Shinoe, H. Takaki ISSP/SRL, Chiba K. Kobayashi KEK, Ibaraki T. Koseki RIKEN/RARF/BPEL, Saitama H. Ohkuma JASRI/SPring-8, Hyogo S. Suzuki LNS, Sendai
	The Super-SOR light source is a Japanese VUV and soft X-ray third-generation synchrotron radiation source, which consists of 1.8GeV storage ring and injector. The beam current is circulated up to 400mA. These accelerators are designed so as to fully meet requirements for top-up injection. In order to realize these operation modes, our vacuum system are required on following conditions. One is to obtain the long lifetime. The other is not to melt the vacuum chamber by irradiating the high flux synchrotron radiation. Finally beam instability is not occurred by large wake fields. We describe the design of the vaccum chamber of Super-SOR and present the recent R&D concerning this system.

WEPKF040	Magnetic Field Measurement of Quadrupole Magnets for S-LSR	alignment, kicker, bunching, beamloading	1693
	T. Takeuchi, K. Noda, S. Shibuya NIRS, Chiba-shi H. Fadil, M. Ikegami, A. Noda, T. Shirai, H. Tongu Kyoto ICR, Uji, Kyoto
	S-LSR is a low energy ion storage/cooler ring. It has 12-quadrupole magnets (QM) with a bore radius of 70 mm and a maximum field gradient of 5 T/m. To suppress and control a magnetic flux in a fringing field of a bending magnet (BM), a field clamp with a thickness of 25 mm was installed in between BM and QM. The distance between the field clamp and QM is 80 mm. 3D calculation represented that the QM field is strongly influenced by the field clamp. Therefore, QMs were designed and optimized in considering the influence of the field clamp. Magnetic field measurements were performed by means of a Hall probe and a long search coil. A magnet field measurement by a Hall probe was carried out together with the field clamp and BM for S-LSR. For 12-quadrupole magnets, the measurement by the long search coil which moves in horizontal direction was carried out. The results for each measurements will be discussed.

WEPLT057	Simulation Results on Cooling Times and Equilibrium Parameters for Antiproton Beams at the HESR	focusing, bunching, impedance, optics	1969
	A. Dolinskii, O. Boine-Frankenheim, B. Franzke, M. Steck GSI, Darmstadt A. Bolshakov, P. Zenkevich ITEP, Moscow A.O. Sidorin, G.V. Troubnikov JINR, Dubna, Moscow Region
	The High Energy Storage Ring HESR is part of the "International Accelerator Facility for Ion and Antiproton Beams" proposed at GSI. For internal target experiments with antiproton beams in the energy range 0.8 GeV to 14.5 GeV a maximum luminosity of 5 inverse nbarn per second and a momentum resolution on the order of 10 ppm have to be attained. Electron cooling is assumed to be the most effective way to counteract beam heating due to target effects and intra-beam scattering. Cooling times and equilibrium parameters have been determined by means of three different computer codes: BETACOOL, MOCAC, and PTARGET. The results reveal that the development of fast, "magnetized" electron cooling with beam currents of up to 1 A and variable electron energies of up to 8 MeV in an extremely homogeneous longitudinal magnetic field of up to 0.5 T is crucial to achieve the required equilibrium beam parameters over the envisaged range of antiproton energies.

WEPLT058	A Space Charge Algorithm for Ellipsoidal Bunches with Arbitrary Beam Size and Particle Distribution	focusing, bunching, impedance, optics	1972
	G. Franchetti, A. Orzhekovskaya GSI, Darmstadt
	For the GSI future project beam loss control of a high intensity bunched beam stored in SIS100 for 10⁶ turns is an important issue. In a recent study (G. Franchetti et al., Phys. Rev. ST Accel. Beams 6, 124201 (2003)) an analytical space charge algorithm was proposed, which allowed noise-free calculations over a large number of turns. Here we present a generalization of this algorithm to arbitrary 3D dimensions and arbitrary distributions observing ellipsoidal symmetry. Applications to long-term tracking with space charge are presented

WEPLT059	Beam Loss Modeling for the SIS100	focusing, bunching, impedance, optics	1975
	G. Franchetti, I. Hofmann GSI, Darmstadt
	In long term storage dynamic aperture is typically regarded as the quantity which has to be maintained sufficiently large in order to prevent beam loss. In the SIS100 of the GSI future project, a beam size occupying a large fraction of the beam pipe is foreseen. This circumstance requires a careful description of the lattice magnetic imperfections. The dynamic aperture is estimated in relation with an optimization of the SIS100 working point. For a space-charge-free bunched beam, estimates of beam loss are computed and compared with dynamic aperture. The impact of space charge will be discussed, and preliminary results on its effect on dynamic aperture and beam loss are presented.

WEPLT060	Linear Coupling Theory of High Intensity Beams	focusing, bunching, impedance, coupling	1978
	G. Franchetti, I. Hofmann GSI, Darmstadt M. Aslaninejad IPM, Tehran
	It is planned to use linear coupling in the SIS18 in order to fully or partially equilibrate the transverse emittances before transfer to the projected SIS100 synchrotron. In this paper we show that space charge significantly modifies the coupling mechanism. In particular the width of the stop-band is dominated by the space charge tune shift for weak skew strength. The conditions are discussed, under which slow crossing of the coupling resonance leads to the desired goal of equalizing emittances while maintaining a sufficient matching of the beam to the ring and extraction optics.

WEPLT061	Influence of Beam Tube Obstacles on the Emittance of the PITZ Photoinjector	focusing, bunching, impedance, coupling	1981
	S. Setzer, W. Ackermann, S. Schnepp, T. Weiland TEMF, Darmstadt
	For detailed analysis of space charge dominated beams inside an RF Photoinjector PIC-Codes like MAFIA TS2/3 can be used. While the interaction of particles with the sourrounding geometries are taken into account, the applicability of such codes is restricted due to simulation time and memory consumption as well as by numercial noise. Therefore only smaller sections of the whole injector can be calculated. On the other hand codes like ASTRA can be used to simulate the whole injector but no interaction between bunch and geometry is included. To make use of the individual advantages of each code discribed above an interface for bidirectional bunch exchange between the two programs has been implemented. This approach allows for applying the right simulation method depending on the physical effects under investigation. To demonstrate the importance of such an approach the results of detailed numerical studies of the impact of beam tube obstacles like the laser mirror on the achievable emittance of the PITZ RF Photoinjector further downstream will be presented.

WEPLT062	Wakefield Calculations for TTF-II	focusing, bunching, impedance, coupling	1984
	I. Zagorodnov, T. Weiland TEMF, Darmstadt M. Dohlus DESY, Hamburg
	In this paper we estimate long- and short-range wake functions for new elements to be used in TESLA Test Facility (TTF) - II. The wake potentials of the LOLA-IV structure and the 3rd harmonic section are calculated numerically for very short bunches and analytical approximations for wake functions in short and long ranges are obtained by fitting procedures based on analytical estimations. The numerical results are obtained with code ECHO for high relativistic Gaussian bunches with RMS deviation up to 0.015 mm. The calculations are carried out for the complete structures (including bellows, rounding of the irises and the different end cell geometries) supplied with ingoing and outgoing pipes. The low frequency spectra of the wake potentials is calculated using the Prony-Pisarenko method.

WEPLT063	Investigation of Cavity Induced Longitudinal Coupled Bunch Mode Instability Behaviour and Mechanisms	focusing, bunching, coupling, electron	1987
	R.G. Heine, P. Hartmann, H. Huck, G. Schmidt, T. Weis DELTA, Dortmund
	The narrowband impedances of RF-resonators in a circular accelerator can drive coupled bunch mode - CBI - instabilities which might spoil the overall beam quality. Often, as in synchrotron radiation light sources e.g. the instability does not lead to beam loss but to a severe degradation of the source brilliance. Investigations of longitudinal CBIs have been performed at the DELTA storage ring with a single DORIS-type cavity for future comparision with the behaviour of a HOM-damped cavity to be tested at DELTA. This resonator is presently developed and built within an EU-collaboration. The beam was deliberately driven into instability using the beam current as well as the cavity temperature as individual parameters. The instability characterisations at low (542 MeV) and high (1,5 GeV) energy exhibit a complex behaviour. The strength of the instability measured by the bunch excursions in the case of longitudinal CBIs, but also the spreading of the instability across neighbouring modes depends on parameters such as beam energy, resonant impedance but also on counteracting mechanisms like synchrotron radiation and Landau damping. The paper will cover the experimental results together with estimations of the influence and mechanism of Landau damping.

WEPLT064	2-nd Order Sextupole Effects on the Dynamic Aperture in HERA-e	focusing, bunching, coupling, electron	1990
	M. Vogt DESY, Hamburg
	During the first year after the luminosity upgrade HERA-e was operated in a mode for which the accessible area in transverse tune space was determined by resonances driven by sextupoles in 2-nd order. It turned out that with typical total incoherent beam beam tune shifts (.05,.08) for 2 IPs this space was too small for stable operation. We have used 2-nd order canonical perturbation theory to analyze the impact of the increased sextupole strengths in the upgraded lattice on the relevant resonance strengths and the detuning. Moreover, we have studied whether it is possible to compensate the resonances with localized octupole schemes (6 or 9 independent magnets) to 1-st and 2-nd order, computed the resulting detuning and compared the results with 6D tracking.

WEPLT065	Hybrid Dry Coolers in Cooling Systems of High Energy Physics Accelerators	focusing, bunching, coupling, electron	1993
	J.-P. Jensen, B. Conrad, U. Schuetz, F.-R. Ullrich, A. Wanning DESY, Hamburg
	Wet water cooling towers in high energy physics accelerators are state of the art. The advantages are robustness, effectiveness and cost-effectiveness. The return water temperature is lower than the air temperature due to cooling via evaporation. The disadvantages are the high water consumption, which becomes more costly in the future, and the soiling of the heat exchangers. If the water source is taken from wells then the drawdown of the ground water level has to be taken into account. DESY plans to use hybrid dry coolers for the two future projects: The XFEL linac and the PETRA 3 synchrotron light source. A hybrid dry cooler is a combination of a dry air cooler during cold and moderate seasons and additional wet cooling during the hot summer season. The cooling surface is wetted by adding water to increase the cooling capability by a factor of 250 %. The hybrid dry cooler saves a lot of water. The water consumption can be reduced by 70% compared to a wet cooling system. This contribution presents the auxiliary water consumption, the requirement of this water and an estimate of the temperature control behaviour of the hybrid dry cooling system.

WEPLT066	Beam Dynamics Study for PETRA III Including Damping Wigglers	focusing, damping, bunching, coupling	1996
	Y.L. Li, K. Balewski, W. Decking DESY, Hamburg
	Damping wigglers will be installed in the storage ring PETRA III to control the beam emittance to 1 nmrad. These wigglers will produce linear and nonlinear perturbations on beam dynamics. A new expanded transport matrix method is developed to solve linear dynamics, and used to match linear lattice functions. The symplectic method is adopted to track particle through the whole ring including the damping wigglers. Halbach?s formulae are used to describe the wiggler field. The main parameters of the wigglers are derived from field calculations. In order to avoid dangerous resonances, tune scanning is implemented to find suitable working points. According to presently known field quality, the nonlinear effects of damping wigglers will not degrade the performance of PETRA III and the dynamic aperture is still larger than the physical aperture.

WEPLT067	Space Charge Problem in Low Energy Super-conducting Accelerator	damping, bunching, coupling, electron	1999
	N.E. Vasyukhin, R. Maier, Y. Senichev FZJ/IKP, Jülich
	At present the super-conducting option of linear accelerators is considered for low energy, and new type of RF cavities is considered for this purpose. However, together with electrodynamics problems we should solve the transverse stability problem, since in structures with external focusing elements the focusing period is longer, and in higher accelerating field the defocusing factor increases as well. In this paper we consider the transverse stability problem, taking into account the non-linear space charge problem. The fundamental mechanism of hallo creation in super-conducting linear accelerators is investigated to minimize the particle losses. The theoretical results are supported by numerical simulation.

WEPLT068	Momentum Compaction Factor and Nonlinear Dispersion at the ANKA Storage Ring	damping, bunching, coupling, booster	2002
	A.-S. Müller, A. Ben Kalefa, I. Birkel, E. Huttel, M. Pont, F. Pérez FZK-ISS-ANKA, Karlsruhe
	The ANKA electron storage ring operates in the energy range from 0.5 to 2.5 GeV. In order to improve machine performance a precise modelling of linear and nonlinear optics is mandatory. Apart from higher order chromaticity also momentum compaction factor and dispersion have to be controlled. In this framework, the higher order momentum compaction factor has been determined exploiting the extraordinary precision of the resonant spin depolarisation method. Furthermore the nonlinear horizontal dispersion was measured as a function of the momentum deviation for different chromaticities. This paper discusses the experimental results and compares the findings to different simulations.

WEPLT069	Investigation of Scraper Induced Wake Fields at ANKA	damping, bunching, coupling, booster	2005
	A.-S. Müller, I. Birkel, E. Huttel, M. Pont, F. Pérez FZK-ISS-ANKA, Karlsruhe F. Zimmermann CERN, Geneva
	The ANKA synchrotron light source operates in the energy range from 0.5 to 2.5 GeV. Typical requirements for light sources include small beam sizes, large lifetimes and high currents to provide the highest possible photon flux. The understanding of impedance and instability related issues is very important in order to improve the machine performance, in particular when small aperture insertion devices are installed that require protection by a scraper. In the framework of an impedance survey the transverse and longitudinal wake fields induced by a vertical scraper have been measured and analysed. This paper reports the beam observations and compares them with the expectation.

WEPLT070	Studies of Current Dependent Effects at ANKA	damping, bunching, coupling, booster	2008
	A.-S. Müller, I. Birkel, E. Huttel, M. Pont, F. Pérez FZK-ISS-ANKA, Karlsruhe F. Zimmermann CERN, Geneva
	The ANKA electron storage ring is operated at energies between 0.5 and 2.5 GeV. A major requirement for a synchrotron light source, such as ANKA, is to achieve a high beam current. A multitude of mostly impedance related effects depend on either bunch or total beam current. This paper gives an overview over the various beam studies performed at ANKA in this context, specifically the observation of current dependent detuning, the dermination of the bunch length change with current from a measurement of the ratio between coherent and incoherent synchrotron tune and an assessment of the effective longitudinal loss factor from the current dependent horizontal closed orbit distortion.

WEPLT071	Longitudinal Resonances and Emittance Growth Using QWR/HWR in a Linac	damping, coupling, booster, focusing	2011
	P. Bertrand GANIL, Caen
	In the frame of the SPIRAL II project at GANIL, we present an analytical approach allowing us to understand in a simple way the longitudinal behaviour of a beam , transmitted in bunching mode or accelerated in a Linac designed with QWR or HWR cavities. In particular, we make appear the strong relationship with the Henon map properties.

WEPLT072	Preliminary Design of the RF Systems for the SPIRAL 2 SC Linac	damping, coupling, booster, focusing	2014
	M. Di Giacomo, B. Ducoudret, J.F. Leyge GANIL, Caen J.F. Denis, M. Desmons, M. Luong, A. Mosnier CEA/DSM/DAPNIA, Gif-sur-Yvette
	In the SPIRAL 2 Linac, a 5 mA, CW , Deuteron beam is accelerated up to 40 MeV, through a normal conducting RFQ and 26 independent-phase SC quarter wave resonators, working at 88,05 MHz. Tube and solid state amplifiers derived from the standard FM transmitter modules are used while a new digital control system has been designed for the feed-back and feed-forward control system. The paper presents the power and low level systems for both the normal and superconducting cavities and results of simulations of the RF system in operating conditions.

WEPLT073	VDHL Design and Simulation of a Fast Beam Loss Interlock for TTF2	damping, coupling, booster, focusing	2017
	A. Hamdi CEA/Saclay, Gif-sur-Yvette M. Luong CEA/DSM/DAPNIA, Gif-sur-Yvette M. Werner DESY, Hamburg
	The TTF2 fast beam loss interlock provides different modes of protection. Based on the differential beam charge monitoring over a macropulse, a pulse slice or bunch-by-bunch, the signal processing time should be as short as the bunch repetition period (110 ns). The signal delivered by the toroid-like inductive current transformer always shows an envelope droop due to its self-inductance to resistance ratio. When the macropulse length is comparable to this ratio, the charge of each bunch must be derived from the difference of the top to the bottom level on the signal. This necessity combined to the various protection modes leads to a digital implementation. All the processing functionalities are designed with VHDL for a Xilinx FPGA. Because the interlock involves other control signals in addition to the toroid signal with specific shapes, which cannot be easily reproduced for the design validation before the TTF2 completion, VHDL provides meanwhile the possibility for an exhaustive validation of the system with a software test bench including all timing information.

WEPLT075	Status Report on the Beam Dynamics Developments for the SPIRAL 2 Project	damping, coupling, booster, focusing	2020
	R. Duperrier, D. Uriot CEA/DSM/DAPNIA, Gif-sur-Yvette P. Bertrand, F. Varenne GANIL, Caen J.-L. Biarrotte IPN, Orsay J.-M. De Conto ISN, Grenoble E. Froidefond LPSC, Grenoble N. Pichoff CEA/DAM, Bruyères-le-Châtel
	The driver for the SPIRAL 2 project aims to accelerate a 5 mA D⁺ beam up to 20 A.MeV and a 1 mA beam for Q/A=1/3 up to 14.5 A.MeV. It operates in a continuous wave regime (cw), is designed for a maximum efficiency in the transmission of intense beams. Recent studies have led to change the reference design. The current design consists in an injector (ECR sources + LEBTs with the possibility to inject from several sources + a Radio Frequency Quadrupole) followed by a superconducting section based on an array of independently phased cavities where the transverse focalisation is performed by warm quadrupoles. This paper presents the beam dynamics studies associated to these new choices, the HEBT design and the fast chopping in the MEBT.

WEPLT076	SPIRAL 2 RFQ Design	damping, coupling, booster, focusing	2023
	R. Ferdinand, G. Congretel, A. Curtoni, O.D. Delferriere, A. France, D.L. Leboeuf, J. Thinel, J.-C. Toussaint CEA/DSM/DAPNIA, Gif-sur-Yvette M. Di Giacomo GANIL, Caen
	The SPIRAL2 RFQ is designed to accelerate at 88MHz two kinds of charge-over-mass ratio, Q/A, particles. The proposed injector can accelerate a 5 mA deuteron beam (Q/A=1/2) or a 1 mA particles beam with q/A=1/3 up to 0.75 MeV/A. It is a CW machine which has to show stable operation, provide the request availability, have the minimum losses in order to minimize the activation constraints and show the best quality/cost ratio. It will be a 4-vane RFQ type, with a mechanical assembly, the global assumption being to build an RFQ without any brazing step. Extensive modelisation was made to ensure a good vane position under RF. A 1-m long hot model prototype is under construction in order to validate the manufacturing concept.

WEPLT077	DESIGN OF A FULL-CUSTOM ACCURATE I-Q MODULATOR	damping, booster, focusing, target	2026
	M. Luong, M. Desmons CEA/DSM/DAPNIA, Gif-sur-Yvette
	The I-Q modulator is a key component in a digital Low Level RF (LLRF) system for amplitude and phase feedbacks. Its residual errors in offset or gain have a strong impact on the dynamic and accuracy of the feedback loops. For some frequencies, commercial I-Q modulators are available on the market. But even in that case, these components are usually designed for broadband communication purposes, and their performances in term of residual errors may not fit the strict requirements on the final amplitude and phase loop stability. Since LLRF systems for accelerators are typically narrow-banded, i.e. limited to few MHz, it is possible to achieve a high directivity and a very accurate coupling for hybrids, and an excellent matching for all subcomponents in a fully custom design. This approach guarantees the lowest residual errors for an I-Q modulator. The principle for the design and the process for the optimization are presented in this paper.

WEPLT078	The IFMIF High Energy Beam Transport Line	damping, booster, focusing, target	2029
	D. Uriot, R. Duperrier, J. Payet CEA/DSM/DAPNIA, Gif-sur-Yvette
	The IFMIF project (International Fusion Materials Irradiation Facility) requests two linacs designed to accelerate 125 mA deuteron beams up to 40 MeV. The linac has to work in CW mode and uses one RFQ and 10 DTL tanks. After extraction and transport, the deuteron beams with strong internal space charge forces have to be bunched, accelerated and transported to target for the production of high neutron flux. This paper presents the high energy beam transport line which provides a flat rectangular beam profile on the liquid lithium target. Transverse uniformisation is obtained by using non-linear mutipole lenses (octupoles and duodecapoles). Beam dynamics with and without errors has been study.

WEPLT079	Non Linear Beam Dynamics and Lifetime on the SOLEIL Storage Ring	damping, booster, target, beamloading	2032
	P. Brunelle, A. Loulergue, A. Nadji, L.S. Nadolski SOLEIL, Gif-sur-Yvette
	The incidence of several non-linear effects on the energy acceptance and beam lifetime has been investigated, using the BETA and TRACY II tracking codes. The effect of all magnets multipolar components has been checked on the working point (18.20; 10.30), especially the decapolar component induced by the H-corrector. The dipolar field, which is created by additional coils in the sextupoles, generates a significant decapolar component which, associated to the distributed dispersion, can reduce significantly the dynamic acceptance at large energy deviations. This effect depends on the natural closed orbit to be corrected: corrector strengths and cross talk between the different decapolar components. Moreover, the sensitivity to the number of correctors, used for correction, has been evaluated. The effect of insertions devices has also been studied, integrating field maps generated by the RADIA code into the tracking codes. With undulators, such as an in-vacuum U20 and an Apple II type HU80 (with different polarization modes), it was shown that the transverse field in-homogeneity and the focusing effects generating beta-beat can affect severely the energy acceptance and the beam lifetime because of resonance excitation.

WEPLT080	Study of Resistive-wall Effects on SOLEIL	damping, booster, target, beamloading	2035
	R. Nagaoka SOLEIL, Gif-sur-Yvette
	The presence of low-gap chambers for insertion devices, along with a relatively small vertical gap of 25 mm chosen for the standard vacuum chambers, implies a significant influence of the resistive-wall on the beam in the future SOLEIL storage ring. A systematic approach was taken to quantify the net contribution by taking into account all local variations of the non-circular chamber cross-sections as well as beta functions. Low multibunch instability thresholds were found in both transverse planes, indicating the necessity of cures, by means of transverse feedback and/or chromaticity shifts. An effort was made to evaluate the effect of metallic coating, particularly that of NEG, which was adopted in all straight sections. The dependence on both resistivity and thickness of NEG was followed. It is found that, the NEG coating nearly doubles the reactive part of the impedance in the frequency range seen by the beam. Implication on the reduction of the transverse mode-coupling instability threshold is discussed. Incoherent tune shifts arising from the non-circular chamber cross-section were also evaluated, including a non-negligible NEG contribution in the short-range wakes.

WEPLT081	Numerical Evaluation of Geometric Impedance for SOLEIL	impedance, damping, booster, target	2038
	R. Nagaoka SOLEIL, Gif-sur-Yvette
	Good knowledge and minimisation of the coupling impedance is of great importance for the future storage ring SOLEIL, envisaged to operate in both high current multibunch and high bunch intensity modes. Three-dimensional computations of the geometric impedance of various vacuum chamber components have been made with the code GdfidL, which allows parallel processing with a cluster of computers, rendering the computation with a small mesh size and a long integrated distance feasible. Many treated objects were found to exhibit large asymmetry in the two transverse planes, as well as resonant behaviour at high frequencies, both of which being non-straightforward to follow with the conventional analytical methods and 2-dimensional calculations. In particular, strongly trapped modes found for the flange impedance resulted in an unacceptably low vertical multibunch instability threshold, which urged a modification of the original cavity-like structure. The dependence of the dipole chamber impedance on the vertical slot size was followed to determine the optimal slot opening. Characteristics of the total broadband impedance obtained, along with relative contributions are also presented.

WEPLT082	General Performances of the Injection Scheme into the SOLEIL Storage Ring	impedance, injection, damping, booster	2041
	M.-A. Tordeux, J. Da Silva, P. Feret, P. Gros, P. Lebasque, A. Mary SOLEIL, Gif-sur-Yvette
	The injection scheme of the electron beam into the Storage Ring of the SOLEIL synchrotron is presented. It corresponds to the new SOLEIL optics : 12 meter long straight section, 2.75 GeV energy, with in addition the requirement for top-up injection mode. Pulsed magnets are described, and in particular the passive septum magnet, the transverse position of which can be adjusted so as to optimise the Touschek beam Lifetime. Tracking of particles has been performed over a large number of turns, taking into account the magnet errors, the high chromaticities and the physical apertures all along the machine (limited vertical apertures due to low gap undulators). Statistical efficiency of the injection has been deduced. Specific requirements for top-up injection have been examined, such as the closure of the injection bump, the residual vertical field and the leakage fields from septa.

WEPLT083	Coherent and Incoherent Tune Shifts Deduced from Impedance Modelling in the ESRF-Ring	injection, damping, booster, target	2044
	T.F. Günzel ESRF, Grenoble
	In single bunch the detuning of the transverse modes m=0,1 and -1 are calculated on the base of an impedance model contructed from element-wise wakefield calculation and the resistive wall impedance of the ESRF-ring. As the vacuum chambers of the ESRF storage ring have notably flat cross sections incoherent wake fields have an impact on the tune shifts as well as coherent wake fields. Compared to tune shift measurements in single bunch the calculated transverse mode detuning can explain half of the tune shift in the vertical plane and almost completely the tune shift in horizontal plane.

WEPLT084	Experimental Frequency Maps for the ESRF Storage Ring	injection, damping, booster, target	2047
	Y. Papaphilippou, L. Farvacque, E. Plouviez, J.-L. Revol, A. Ropert ESRF, Grenoble J. Laskar IMCCE, Paris Ch. Skokos Academy of Athens, Athens
	Experimental frequency maps have already revealed many unknown characteristics of the ESRF storage ring non-linear dynamics. In the past year, several efforts were undertaken in order to establish this technique as an operational on-line tool. The acquisition time was significantly reduced by collecting data from a dedicated fast BPM system. The problem of beam decoherence was limited by establishing a method for accurate tune determination in a small number of turns, using the information from all the BPMs around the ring. The possibility to explore the off-momentum dynamics by exciting the beam, with synchronous transverse and longitudinal kicks was also investigated. Finally, measurements of resonance driving term amplitudes and phase advances were used to identify the efficiency of resonance corrections.

WEPLT085	Vertcal Effective Impedance Mapping of the ESRF Storage Ring	injection, impedance, damping, vacuum	2050
	T. Perron, L. Farvacque, E. Plouviez ESRF, Grenoble
	Transverse impedance increase due to installation of low gap vacuum chambers is a general effect observed in synchrotron light sources. ESRF has been sensitive to this increase of impedance, as its single bunch threshold has dramatically decreased. This paper presents a method based on closed orbit distortion measurements, witch allows to measure locally the vertical effective impedance. Results of measurements performed on low gap vacuum chambers and in-vacuum ondulators are presented. As an extension to this experiment, a new global method is discussed. This method, also based on closed orbit measurement allows measuring simultaneously all areas of high impedance in the machine

WEPLT086	Non Gaussien Transverse Distributions in a Stochastic Model for Beam Halos	injection, impedance, damping, vacuum	2053
	N. Cufaro Petroni INFN-Bari, Bari S. De Martino, S. De Siena, F. Illuminati Universita' degli Studi di Salerno, Dipartimento di Fisica E.R. Caianiello, Baronissi
	The formation of the beam halo in charged particle accelerators is studied in a dynamical stochastic model for the collective motion of the particle beam. The density and the phase of the charged beam obey a set of coupled nonlinear hydrodynamic equations with time-reversal invariance. The linearized theory for this collective dynamics is given in terms of a classical Schroedinger equation. Self-consistent solutions with space-charge effects lead to quasi-stationary beam configurations with enhanced transverse dispersion and transverse emittance growth. In the limit of a frozen space-charge core it is possible to determine and study the properties of stationary, stable core-plus-halo beam distributions. We explore the effect of non-Gaussian transverse distributions. In this case the underling stochastic process is allowed to jump, and the transverse distribution tails are heavier than in the Gaussian case giving rise to a halo effect. The stationary transverse distribution plays the role of an attractor for every other distribution, and we give an estimation of the time needed by a non stationary, halo-free distribution to relax toward the stationary distribution with a halo.

WEPLT090	Nonlinear Evolution of the Beam in Phase Space at Elettra	injection, impedance, damping, vacuum	2056
	S. Di Mitri, L. Tosi ELETTRA, Basovizza, Trieste
	Phase space in the Elettra storage ring has been investigated. The beam is kicked and the coordinates of the bunch centroid are acquired for at least 1000 turns. A Hilbert transform has been used to deduce the evolution of beam phase space from position coordinates. Several nonlinear effects have been detected, such as the amplitude dependence of the betatron tune, the presence of high order and coupling resonances. Fixed points have been evidenced as well as the behaviour of the beam in their neighbourhood. Scans in lifetime versus tune confirm the limiting effect of the observed resonances on the region of regular motion.

WEPLT091	Frequency Map Analysis with the Insertion Devices at ELETTRA	impedance, damping, vacuum, booster	2059
	S. Di Mitri, L. Tosi ELETTRA, Basovizza, Trieste L.G. Liu SSRF, Shanghai
	Frequency map analysis is a very efficient technique for the understanding of the resonances which may affect the stability of the electrons. Measurements correlated to simulations can provide a method to improve beam lifetime and injection efficiency that is particulary important in the case of top up operation. In this paper, the results of frequency map measurements and simulations for the ELETTRA storage ring are presented both for the bare lattice as well as for the case in which insertion devices are operational.

WEPLT092	Equilibrium Longitudinal Distribution for Localized Regularized Inductive Wake	impedance, damping, vacuum, booster	2062
	S. Petracca, T. Demma U. Sannio, Benevento K. Hirata GUAS, Kanagawa
	In a recent paper [] we have shown that a localized wake assumption and the Gaussian approximation for the longitudinal beam distribution function can be used to understand the nature of the stationary solutions for the inductive wake, by comparison between the resulting map and the Haissinski equation, which rules the (less realistic) case of a uniformly distributed wake. In particular we showed the non-existence of solutions of Haissinski's equation when the inductive wake strength exceeds a certain threshold [] to correspond to the onset of chaos in the map evolving the moments of the beam distribution from turn to turn. In this paper we use the same formalism to confirm that as noted in [] for Haissinski's equation, a steady state solution for the longitudinal phase space distribution function always exists if a physically regularized inductive wake, which satisfies an obvious causality condition, is used. S. Petracca and Th. Demma, Proc. of the 2003 PAC, IEEE Press, New York, 2003, ISBN 0-7803-7739-9, p.2996.** Y. Shobuda and K. Hirata, Part. Accel. vol. 62, 165 (1999).

WEPLT093	Electromagnetic Fields of an Off-axis Bunch in a Circular Pipe with Finite Conductivity and Thickness - I	impedance, damping, vacuum, booster	2065
	S. Petracca, L. Cappetta, T. Demma U. Sannio, Benevento
	The electromagnetic field produced by a bunched beam in a circular pipe is usually computed under the assumption that the field penetration(skin depth) is far less than the wall thickness. Chao [] gave a formula which exploits the wall thickness, but his result is restricted to the monopole term. Piwinski [] treated the case of a metal coated ceramic wall, when the coating thickness is much smaller than the skin-depth, but his analysis is also limited to the monopole term.In this paper we solve the problem in full generality, by providing an exact (Green's functions) solution for the field of an off-axis point particle running at constant velocity in a circular pipe with finite wall conductivity and thickness. A.W. Chao, Phys. of Collective Beam Instab. in High En. Accel., Wiley,1993** S. Piwinski, DESY 1972/72

WEPLT094	Electromagnetic Fields of an Off-axis Bunched Beam in a Circular Pipe with Finite Conductivity and Thickness - II	impedance, damping, vacuum, booster	2068
	S. Petracca, L. Cappetta, T. Demma U. Sannio, Benevento R.P. Croce Universita' degli Studi di Salerno, Dipartimento di Fisica E.R. Caianiello, Baronissi
	The general exact solution exploited [] is applied, introducing suitable dimensionless parameters, and using appropriate asymptotic limiting forms, to compute the wake field multipoles for the different paradigm cases of LHC and DAPHNE. R. P. Croce, Th. Demma, S. Petracca "Electromagnetic Fields of an Off-axis Bunch in a Circular Pipe with Finite Conductivity and Thickness", these proceedings

WEPLT095	Modified Polarizabilities and Wall Impedance for Shielded Perforated Beam Pipes with General Shape	damping, vacuum, booster, target	2071
	S. Petracca, T. Demma U. Sannio, Benevento
	We extend previous results [] concerning the modified polarizability of (electrically small) holes/slots in the wall of a circular beam liner surrounded by a coaxial circular tube to the most general liner and cold bore geometries. We obtain an equivalent wall impedance to describe the electromagnetic boundary conditions at perforated walls for this most general case, and use a general perturbational approach [] for computing the pertinent longitudinal and transverse coupling impedances. R.L. Gluckstern, CERN SL 92-06 (AP), 1992, CERN SL 92-31 (AP), 1992; R.L. Gluckstern, B. Zotter, CERN SL 96-56 (AP), 1996.** S. Petracca, Part. Acc., {\bf 50}, 211, 1995; id., Phys. Rev. E, 60 (3),1999.

WEPLT097	Beam Loading in the RF Deflector of the CTF3 Delay Loop	damping, vacuum, booster, target	2074
	D. Alesini, F. Marcellini INFN/LNF, Frascati (Roma)
	In this paper we describe the impact of the beam loading in the RF deflectors on the transverse beam dynamics of the CTF3 Delay Loop. The general expression for the single passage wake field is obtained. A dedicated tracking code has been written to study the multi-bunch multi-turn effects on the transverse beam dynamics. A complete analysis for different machine parameters and injection errors is presented and discussed. The numerical simulations show that the beam emittance growth due to the wake field in the RF deflectors is small.

WEPLT098	Experience with Long Term Operation with Demineralized Water Systems at DAFNE	damping, vacuum, booster, target	2077
	L. Pellegrino INFN/LNF, Frascati (Roma)
	During eight years operation of the Dafne water cooling system we coped with several critical situations and managed successfully specific upgrades to the demineralized water system. Here we revise critically the collected data and the experience gained in the field of copper corrosion and related water treatment.

WEPLT100	Planar Electron Sources and the Electron Trap ELTRAP	electron, damping, plasma, vacuum	2080
	M. Cavenago INFN/LNL, Legnaro, Padova G. Bettega, F. Cavaliere, A. Illiberi, R. Pozzoli, M. Romé, L. Serafini INFN-Milano, Milano
	Filamentation and other space charge effects (both transverse and longitudinal) of intense electron beams, found for example in rf photoinjectors (beam energy 1 MeV, current 100 A), are easily studied in small voltage traps and drift channels (0.01-10 kV), keeping the same perveance order. A suitable Malmberg-Penning trap, named ELTRAP, installed and operated at the University of Milan, is briefly described; trap length ranges from 10 cm to 1 m; an uniform magnetic field confines electron radially. Several experimental regimes were investigated with the internal CW planar electron source: plasma, beam-plasma, beam, depending on the injection/extraction method chosen. Evolution of electron vortices and virtual cathode formation is documented; analogy with meteorologic and astrophysical plasma is discussed. Upgrading with an external laser pulsed electron source is in course. Larger planar sources are also under construction. (Main classification 4: Beam Dynamics and Electro-magnetic Fields; D03 High Intensity, Incoherent Instabilities, Space Charge, Halos, Cooling; Other classification 8: Low and Intermediate Energy Accelerators and Sources; T12 Beam Injection/Extraction and Transport; T02 Lepton sources)

WEPLT101	On-line Mechanical Instabilities Measurements and Tuner Development in SC Low-beta Resonators	electron, plasma, vacuum, booster	2083
	A. Facco, E. Bissiato, S. Canella, D. Carlucci, M. Lollo, F. Scarpa, D. Zenere INFN/LNL, Legnaro, Padova
	The use of high-Q and small rf bandwidth superconducting quarter wave resonators made of bulk niobium put severe requirements to the helium bath pressure stability to avoid cavity detuning. This is not always possible, and cavity detuning caused by slow pressure changes must be precisely followed by the cavity tuner. The LNL philosophy is based on mechanical damping of cavity vibrations and mechanical tuning in feedback for slow frequency compensation. The old-fashioned tuners installed in the ALPI linac had significant performance limitations. To replace them, we have designed, constructed and tested a new tuner which integrates the LNL system and control with the TRIUMF, backlash-free tuner leverage design. The new tuner is designed to compensate pressure changes up to 100 mbar/minute with a precision of 0.5 Hz, and it will be installed in the ALPI resonators. An upgraded prototype for future applications includes a piezoelectric actuator for fast tuning. Tuner characteristics and first test results will be presented. This system is extendable to other low-beta cavity types like superconducting rfqs.

WEPLT102	Electron Cooling Experiments at HIMAC Synchrotron	plasma, vacuum, booster, target	2086
	K. Noda, T. Furukawa, T. Honma, S. Shibuya, D. Tan, T. Uesugi NIRS, Chiba-shi T. Iwashima AEC, Chiba I.N. Meshkov, E. Syresin JINR, Dubna, Moscow Region S. Ninomiya RCNP, Osaka
	In the HIMAC synchrotron, the electron cooling experiments have been carried out since 2000 in order to develop new technologies in heavy-ion therapy and related research. Among of them, especially, the cool-stacking method has been studied to increase the intensity of heavy ions such as Fe and Ni in order to study the risk estimation of the radiation exposure in space. The simulation was carried out in order to optimize the stacking intensity under various the injection periods. In addition, the beam heating by the RF-KO and the clearing the secondary ion in the cooler were applied to avoid the instability occurred when the beam density became high. We will report the experiment results.

WEPLT103	Radiation Damage in Magnets for Undulators at Low Temperature	radiation, plasma, vacuum, booster	2089
	T. Bizen, X. Maréchal, T. Seike JASRI/SPring-8, Hyogo Y. Asano JAERI/SPring-8, Hyogo T. Hara, H. Kitamura, T. Tanaka RIKEN Spring-8 Harima, Hyogo D.E. Kim, H.S. Lee PAL, Pohang
	Nd2Fe14B permanent magnets are used in many insertion devices for its good magnetic and mechanical properties. However, the radiation sensitivity of the magnets would be concern when they are used in a strong radiation environment. It is known that these magnets with very high coercivity show high resistance to radiation, though the substance for increasing the coercivity decrease the remanence. The coercivity and remanence of this magnet exhibit negative dependence against temperature, so it is expected to these magnets to show high remanence and high resistance to radiation at low temperature. The idea of using magnets at low temperature leads the new concept of the cryogenic undulators. In this report, the experimental results of the radiation damage of permanent magnets at low temperature are shown.

WEPLT105	Beam-Beam Effects Measured Using Gated Monitors at KEKB	radiation, plasma, vacuum, electron	2092
	T. Ieiri, Y. Funakoshi, T. Kawamoto, M. Masuzawa, M. Tawada, M. Tobiyama, S.S. Win KEK, Ibaraki
	KEKB is a multi-bunch, high-current, electron/positron collider for B meson physics. The two beams collide at one interaction point (IP) with a finite horizontal crossing angle and with a bunch-space of 6 to 8 ns. The luminosity of KEKB is the best in the world. The collision is performed by carefully adjusting a horizontal orbit bump of the electron beam at IP, which results in a horizontal offset to obtain the best luminosity. In order to investigate the asymmetric beam-beam effects, beam parameters of collision and non-collision bunches were compared using beam monitors capable of selecting a specific bunch in a bunch train. The beam-beam kick and the beam-beam tune-shift were obtained by the gated beam-position monitor and by the gated tune monitor. It was found that the horizontal offset was negligibly small in the case of a wide bunch-space of 48 ns. This result suggests that the horizontal offset is related to wake fields including electron-cloud effects.

WEPLT106	Growth and Suppression Time of an Ion-related Vertical Instability	radiation, plasma, octupole, booster	2095
	T. Miyajima, Y. Kobayashi, S. Nagahashi KEK, Ibaraki
	In the KEK Photon Factory electron storage ring, a vertical instability has been observed in a multi-bunch operation mode. The instability can be suppressed by octupole magnetic field in routine operation. Since the instability depends on a vacuum condition in the ring, it seems that it is an ion-related phenomenon. In order to study this instability, we measured the growth and the suppression time of it with the pulse octupole magnet system, which can produce the octupole field with rise and fall time of around 1.2msec. We obtained the result that the instability was grown slowly compared with to suppress it, and the growth time depended on the fill pattern of the bunch train and the beam current per bunch.

WEPLT107	Nonlinear field Effects in the JPARC Main Ring	radiation, sextupole, plasma, proton	2098
	A.Y. Molodojentsev, S. Machida, Y. Mori KEK, Ibaraki
	Main Ring (MR) of the Japanese Particle Accelerator Research Complex (JPARC) should provide acceleration of the high-intensity proton beam from the energy of 3GeV to 50 GeV. The expected beam intensity is 3.3·10¹⁴ ppp and the repetition rate is about 0.3 Hz. The imaginary transition lattice of the ring was adopted, which has the natural linear chromaticity about (-30) for both transverse phase planes. The expected momentum spread of the captured particles before the acceleration is less than 0.007. Two independent families of the chromatic sextupole magnets are use to eliminate the linear chromatic tune shift. This chromatic sextupole field nonlinearity will excite the normal 'octupole' resonances and will lead to the amplitude dependent tune shifts in both transverse phase planes. Additional sextupole magnets are planed to excite the third-order horizontal resonance, which will be used for the slow extraction. Incoherent tune shift of the low-energy proton beam is about (-0.16) so that some particles could cross nearest low-order resonances. Optimization of the 'bare' working point of MR at the injection energy has been performed to minimize the influence of the linear coupling and high-order coupling resonances. Excitation of the linear coupling resonance has been introduced by the realistic misalignment errors adopted for MR. The 'bare' working point during the slow extraction has been analyzed. The influence of the normal sextupole resonances on the large amplitude particle behavior at the scraper location has been studied including random sextupole field component of the MR bending magnets. Realistic distortion of the ideal ring super-periodicity by the injection kicker magnets has been included in the tracking procedure for the on- and off-momentum particles. Finally, correction schemes have been considered for most dangerous resonances around the optimized 'bare' working point. The space-charge effects of the proton beam have not been included in this study.

WEPLT108	Diffusion caused by Beam-beam Interactions with Couplings	radiation, sextupole, plasma, proton	2101
	K. Ohmi, S. Kamada, K. Oide, M. Tawada KEK, Ibaraki
	A system of colliding two beams is strong nonlinear in multi-dimension. In such a system, a symplectic diffusion called Arnold diffusion occurs, with the result that the beams are enlarged and the luminosity is degraded in circular colliders. We discuss the diffusion seen in beam-beam inetraction at a circular accelerator, especially finite crossing angle and/or x-y coupling errors enhance the diffusion.

WEPLT109	Simulation of Ep Instability for a Coasting Proton Beam in Circular Accelerators	radiation, sextupole, plasma, booster	2104
	K. Ohmi, T. Toyama KEK, Ibaraki G. Rumolo GSI, Darmstadt
	ep instability is discussed for a coasting beam operation of J-PARC 50 GeV Main Ring. Our previous study (PAC2003) was focussed only ionization electron. We now take into account electrons created at the chamber wall due to proton loss and secondary emission with higher yield than ionization.

WEPLT110	Specific Beam Dynamics in Super-bunch Acceleration	radiation, sextupole, plasma, booster	2107
	Y. Shimosaki, E. Nakamura, K. Takayama, T. Toyama KEK, Ibaraki K. Horioka, M. Nakajima TIT, Yokohama K. Koseki GUAS/AS, Ibaraki K. Torikai Kyushu University, Fukuoka M. Watanabe RIKEN, Saitama
	Proof-of-principle experiments on the induction synchrotron concept using the KEK 12-GeV PS makes progress, in which RF bunches and a super-bunch will be accelerated with a long step voltage generated in the induction accelerating gaps. In order to give a guide for super-bunch acceleration, the beam stabilities against a droop and a fluctuation of the accelerating voltage have been examined by using a simulation. The droop voltage gives an additional focusing or defocusing force in the longitudinal direction, which leads the mismatching beyond the transition energy. Furthermore, the extremely slow fluctuation of the accelerating voltage causes a lowest-order resonance near the transition. These induce a serious emittance blow-up in the longitudinal, so that the compensating manners will be presented. Moreover, the other issues such as head-tail instability and intra beam scattering will be discussed.

WEPLT113	Development of New Hydrostatic Levelling Equipment for Large Next Generation Accelerator	radiation, sextupole, plasma, booster	2110
	S. Takeda KEK, Ibaraki
	The Hydrostatic Levelling Systems (HLS) are installed and commissioned in many laboratories. We have developed a new type hydrostatic levelling equipment for the large future accelerator. The designing points are as followings: (1) use of half filled water level sensor instead of the usual full filled level sensor, (2) the capacitive sensor is supported by an invar rod and (3) use of digitized signal transfer system. These three points are very important factor to apply the leveling system to large next generation accelerator in order to obtain good temperature stability and being free from the environmental electronic noises. We have obtained a typical resolution of the equipment as 0.3 micron-meter, though usual HLS shows the value ten times as much. We are going to show a detailed report about the system including data obtained.

WEPLT114	Field Measurements in the AGS Warm Snake	radiation, sextupole, plasma, booster	2113
	J. Takano, M. Okamura RIKEN, Saitama R. Alforque, R. Belkin, G. Ganetis, A.K. Jain, W.W. MacKay, T. Roser, R. Thomas, J. Tuozzolo BNL, Upton, Long Island, New York T. Hattori RLNR, Tokyo
	A new warm snake has been produced for avoiding the transverse coupling resonance in the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). The warm snake is the world?s first normal conducting helical dipole partial snake which has a double pitch structure to allow spin rotation with no net beam offset or deflection with a single magnet. The warm snake is 2.6m long, and has a field of 1.5 Tesla for a 9 degrees spin rotation. The pitches, current density, and shims were optimized by using OPERA_3D / TOSCA. The magnetic field harmonics have been measured using a system of 51 mm long, 34 mm radius tangential coils. The axial variation of the dipole field angle agrees very well with the calculations, indicating no significant construction errors. However, the measured transfer function shows a discrepancy of 4% which may be caused by BH-curve differences, deformation of the iron and packing factor of the laminations. To correct the beam trajectory the operating current was adjusted and shims were installed on the end plates. These optimization studies, and comparison with measurements, will be shown.

WEPLT115	A Study of Transverse Resonance Crossing in FFAG	radiation, sextupole, plasma, resonance	2116
	M. Aiba University of Tokyo, Tokyo S. Machida, Y. Mori KEK, Ibaraki
	A study of "resonance crossing" in FFAG accelerator is described in this paper. A deviation of FFAG guiding field in actual magnet breaks zero chromaticity condition, and tunes cross resonance while acceleration. In order to avoid a critical beam loss or emittance growth, nominal tune should be chosen so as not to cross low-order resonances. However, crossing higher order resonance can be critical and that depends on the parameters such as crossing speed, excitation magnitude and initial beam emittance. We will present analytical model and simulation study in various parameter space.

WEPLT116	Lattice Design and Cooling Simulation at S-LSR	radiation, sextupole, plasma, resonance	2119
	T. Shirai, H. Fadil, S. Fujimoto, M. Ikegami, A. Noda, M. Tanabe, H. Tongu Kyoto ICR, Uji, Kyoto T. Fujimoto, H. Fujiwara, K. Noda, S. Shibuya, T. Takeuchi NIRS, Chiba-shi M. Grieser MPI-K, Heidelberg H. Okamoto, Y. Yuri HU/AdSM, Higashi-Hiroshima E. Syresin JINR, Dubna, Moscow Region
	A compact ion cooler ring, S-LSR is under construction in Kyoto University. The circumference is 22.557 m and the maximum magnetic rigidity is 1 Tm. One of the important roles of S-LSR is a test bed to examine the lowest temperature limit of the ion beams using cooling techniques. The ultimate case is a crystalline one. The ring optics of S-LSR has a high super periodicity and a low phase advance to reduce the beam heating from the lattice structure. S-LSR has an electron beam cooling device and a laser cooling system for Mg. The simulation results show the possible limit of the ion beam temperature and the dependence on the operating betatron tunes.

WEPLT117	Design of a Third Harmonic Superconducting RF System at PLS	radiation, sextupole, plasma, resonance	2122
	E.-S. Kim, M.-H. Chun, H.-G. Kim, K.-R. Kim, I.-S. Park, Y.-U. Sohn, J.S. Yang PAL, Pohang J.-K. Ahn, J.-S. Cho Pusan National University, Pusan
	A superconducting third harmonic rf system has been designed in the PLS to raise beam lifetime. Expected beam lifetimes verse beam emittance and operational beam current are presented. A multibunch multiparticle tracking simulation is performed to investigate energy spread, bunch-lengthening and beam instabilities due to the rf cavities. The parameters of the designed rf cavity, designed cryogenic system and estimation of heat load are also presented.

WEPLT118	Performance of the TU/e 2.6 Cell Rf-photogun in the 'Pancake' Regime	radiation, sextupole, resonance, ion	2125
	S.B. van der Geer, G.J.H. Brussaard, O.J. Luiten, M.J. Van der Wiel TUE, Eindhoven G. Pöplau Rostock University, Faculty of Engineering, Rostock M.J. de Loos PP, Soest
	The 2.6 cell rf-photogun currently in operation at Eindhoven University of Technology has been designed as a booster for a 2 MeV semi-DC accelerator with a field of 1 GV/m. In this paper we present GPT simulation results of the TU/e gun, operated without its pre-accelerator, in the low-charge short-pulse regime. The main part of the paper describes detailed calculations of bunch lengthening due to path-length differences and space-charge effects, making use of high-precision field-maps and the newly developed 3D mesh-based space-charge model of GPT. It is shown that with the present set-up bunches can be produced that are well suited for injection into a planned experiment for controlled acceleration in a plasma-wakefield accelerator.

WEPLT119	Beam Instabilitiy Studies of BEPC and BEPCII	radiation, sextupole, resonance, ion	2128
	J.Q. Wang, Z.Y. Guo, Y.D. Liu, Q. Qin, Z. Zhao, D.M. Zhou IHEP Beijing, Beijing
	BEPC has been well operated for more then 10 years, and it will be upgraded to a double ring electron positron collider using the existing tunnel, namely BEPCII. This paper describes the recent studies on beam instabilities in BEPC for the improvement of its performance as well as for BEPCII. The instabilities caused by impedance and two-stream effect are investigated. The experimental and simulation results are reported.

WEPLT120	Control Environment for the Superconducting Insertion Devices at NSRRC	radiation, sextupole, insertion, resonance	2131
	J. Chen, C.-K. Chang, K.-T. Hsu, K.H. Hu, C.H. Kuo, C.-J. Wang NSRRC, Hsinchu
	To enhance hard X-ray capability in the 1.5 GeV storage ring of NSRRC to serve the rapidly growing X-ray user community in Taiwan, the storage ring was installed two superconducting insertion devices. Three more superconducting insertion devices are in planning. A 6 Tesla superconducting wavelength shifter was installed in mid-2002. A 3.2 Tesla superconducting multi-pole wiggler was installed in December of 2003. Control system and operation environment have been set up to support the operation of the superconducting insertion devices. The implementation and operation experiences will be summarized in this report.

WEPLT121	Computer Simulation of Equilibrium Electron Beam Distribution in the Proximity of 4th Order Single Nonlinear Resonance	radiation, sextupole, insertion, resonance	2134
	T.-S. Ueng, C.-C. Kuo, H.-J. Tsai NSRRC, Hsinchu A. Chao SLAC, Menlo Park, California
	The beam distribution of particles in an electron storage ring is distorted in the presence of nonlinear resonances. A computer simulation is used to study the equilibrium distribution of an electron beam in the presence of 4th order single nonlinear resonance. The results are compared with that obtained using an analytical approach by solving the Fokker-Planck equation to first order in the resonance strength. The effect of resonance on the quantum lifetime of electron beam is also compared and investigated.

WEPLT122	Investigation of Microwave Instability on Electron Storage Ring TLS	radiation, sextupole, resonance, ion	2137
	M.-H. Wang NSRRC, Hsinchu A. Chao SLAC, Menlo Park, California
	With the planned installation of a superconducting rf system, the new operation mode of TLS, the electron storage ring at NSRRC, is expected to double the beam intensity. Several accelerator physics topics need to be examined. One of these topics concerns the beam instability of single-bunch longitudinal microwave instability. We consider different approaches to measure the effective broad band impedance. We compare these measurement results with each other and to the old data []. The new measurements of effective broad band impedance are higher than the old measurement since between these two sets of measurements several narrow gap insertion devices were installed into the storage ring. We calculate the threshold current of microwave instability with a mode-mixing analysis code written by Dr. K. Oide of KEK []. We also develop a multi-particle tracking code to simulate the instability. The results of simulation and measurement are compared and discussed. We conclude that the doubling of beam current will not onset the microwave instability even without a Landau cavity to lengthen the bunch. M.H. Wang, et al.,"Longitudinal Beam Instability Observation with streak Camera at SRRC", proceeding of 1996 European Particle Accelerator Conference, pp. 1120** K. Oide, "Longitudinal Single-Bunch Instability in Electron Storage Rings", KEK Preprint 90-10

WEPLT123	Engineering Design of High-current 81.36 MHz RFQ with Elliptic Coupling Windows	radiation, sextupole, resonance, target	2140
	D. Kashinskiy, A. Kolomiets, S. Minaev, V. Pershin, B.Y. Sharkov, T. Tretyakova ITEP, Moscow
	Four-vane RFQ structure with elliptic coupling windows has been originally developed at ITEP for injection into ITEP-TWAC synchrotron/storage ring complex, being lately adapted for RIA project too. As the electrodynamics simulations show, this structure combines the high efficiency with the operating mode stability against asymmetric detuning and electrode misalignment. A considerable reduction of structure diameter due to coupling windows becomes important for low frequency range which is necessary for the heavy ion acceleration. At the same time, the electrode configuration allows the efficient cooling and high duty factor operation. A mechanical design of 81 MHz, 1.6 MeV/u, 6 m long heavy ion RFQ section is discussed. The outer tank is made of two layers, steel and copper, joined by using the thermal diffusion technology. Each electrode is supplied with the alignment mechanism and connected to the tank by the flexible conducting insert. The whole setup is in manufacturing now.

WEPLT126	Beam Dynamics Simulation in High Energy Electron Cooler	radiation, sextupole, resonance, electron	2143
	A.V. Ivanov, V.M. Panasyuk, V.V. Parkhomchuk, V.B. Reva BINP SB RAS, Novosibirsk
	The article deals with electron beam dynamics in projected high energy electron cooler. Classical electrostatic scheme with several MeV electron energy is considered. The increase of transversal energy of electrons in an accelerating section, in bends and at the matching point of magnetic fields is calculated. In order to calculate beam behavior in bends with electrostatic compensation of centripetal drift new ELEC3D electro- and magnitostatic 3D code is developed. BEAM code is used for simulation of dynamics in an accelerating section. The methods of keeping low transversal energy are estimated.

WEPLT128	Charge Particle Source for Industrial and Research Accelerators Operating at the Poor Vacuum Conditions	radiation, sextupole, resonance, electron	2146
	E.O. Popov, A.A. Pashkevich, S.O. Popov, A.V. Vitugov IOFFE, St. Petersburg
	We investigated the original method of fabrication of the great number of emitting tips by pulling liquid metal through the holes in track membrane under influence of electric field. The track membranes are produced by cyclotron of Physicotechnical Institute. This method enables to fabricate up to 1·10⁸ emitting tips per square cm. Special test facility to investigate emitter parameters operating at different values of background residual gas pressure was designed and developed. The liquid metal multiple tip field emitters possess some unique characteristics which are attractive in accelerators for material irradiation: unlimited life expectancy, large current densities (about 100 mA per sq. cm), practically unlimited surface, stable emission in poor vacuum.

WEPLT133	On Beam Dynamics Optimization	radiation, sextupole, resonance, electron	2149
	D.A. Ovsyannikov, S.V. Merkuryev St. Petersburg State University, St. Petersburg
	Mathematical optimization methods are widely used in designing and construction of charged particle accelerators. In this paper new approach to beam dynamics optimization is considered. Suggested approach to the problem is based on the analytical representation for variation of examined functionals via solutions of special partial differentional equations. The problem of optimization is considered as a problem of mutual optimization chosen synchronous particle motion and charged particles beam at whole. This approach was applied to the beam dynamics optimization for RFQ structures.

WEPLT136	Lattice Studies For The MAX-IV Storage Rings	sextupole, resonance, target, beamloading	2152
	H. Tarawneh, M. Eriksson, L.-J. Lindgren, S. Werin MAX-lab, Lund B. Anderberg AMACC, Uppsala E.J. Wallén ESRF, Grenoble
	The lattice for the future MAX-IV storage rings at MAX-Lab has been studied, The MAX IV facility consists of two similar rings operated at 1.5 GeV and 3 GeV electron energies, The ring consists of 12 supercells each built up by 5 unit cells and matching sections. The high periodicity of the lattice combined with the high gradients in the small gap dipole magnets yield a small emittance of 1 nm.rad, good dynamic aperture and momentum acceptance. In the matching section, a soft end dipole magnet is introduced to reduce the synchrotron radiation power hitting the upstream straight section.

WEPLT137	Higher Order Modes in the New 100 and 500 MHz Cavities at MAX-lab	sextupole, resonance, target, beamloading	2155
	H. Tarawneh, Å. Andersson, M. Bergqvist, M. Brandin, M. Eriksson, L. Malmgren MAX-lab, Lund
	The MAX-II electron storage ring operates exclusively in multi-bunch mode with all buckets filled. Damping of the longitudinal higher order mode (HOM) instabilities has successfully been provided by passive third harmonic 1.5 GHz cavities. With a new RF employing three 100 MHz capacity loaded cavities and a fifth harmonic Landau cavity installed, a study of the HOM impedances, and related threshold instability currents, is necessary. Measurements and calculations so far, are being presented.

WEPLT138	Laser Cooling of Electron Bunches in Compton Storage Rings	sextupole, laser, resonance, emittance	2158
	E.V. Bulyak NSC/KIPT, Kharkov
	Self-consistent dynamics of a bunch circulating in the Compton storage ring has been studied analytically. Disturbances from both the synchrotron and Compton radiations were taken into account. The emittances in laser-dominated rings (where the synchrotron energy losses are much smaller then the Compton ones) were evaluated. The resultant emittances (synchrotrons plus Comptons) were compared with the synchrotrons. As were shown, the longitudinal degree of freedom is heated up due to Compton scattering. Almost the same conclusion is valid for the vertical uncoupled betatron emittance. Since it is impossible in principle to get zero dispersion in the banding magnets, the radial emittance almost always cooling down by laser. Therefore in practical cases of coupled transverse oscillations with the horizontal emittance determining the vertical one, the laser will cool down the transverse degrees of freedom.

WEPLT140	New Abilities of Computer Code DeCA	sextupole, laser, resonance, emittance	2161
	P. Gladkikh, A.Y. Zelinsky NSC/KIPT, Kharkov
	In the paper the status and new abilities of computer code package DeCA (Design of Cyclic Acclerators) are described. The main effort of the code developers were made to creation of software capable to simulate intrabeam scattering effect and Compton scattering. In addition modules for calculation of the second order dispersion and momentum compaction factor were developed.

WEPLT141	Beam-power Calibration System for Industrial Electron Accelerators	sextupole, laser, resonance, emittance	2164
	V.L. Uvarov, S.P. Karasyov, V.I. Nikiforov, R.I. Pomatsalyuk, V.A. Shevchenko, I.N. Shlyakhov, A.Eh. Tenishev NSC/KIPT, Kharkov
	Modern electron accelerators for industrial application provide particle energy of up to 10 MeV and beam power of up to 100 kW. Such a beam is ejected into an air using a scanning system. The measuring channel based on a total-absorption calorimeter of flow-type for a beam calibration with respect to energy flow is designed. The processes of beam interaction with the primary measuring converter (a water-cooled beam absorber of especial geometry) were previously studied using a computer simulation. The metering circuit of the channel is made as a stand-alone module with LCD display and control keypad. It performs the operations of temperature measurement at the input and output of the absorber, as well as a water flow-rate determination. The absorbed power is calculated from measured parameters and then is displayed and stored into channel memory using appropriate software. The process is carried out both in off-line mode and under control of the external PC via a serial interface of RS-232 type.

THPLT007	New Beam Profile Monitor Based on GEM Detector for the AD Transfer and Experimental Lines	linac, laser, simulation, insertion	2469
	J. Bosser, K. Gnanvo, J. Spanggaard, G. Tranquille CERN, Geneva
	Many multi-wire proportional chambers, (MWPC's), are installed on the CERN Antiproton Decelerator (AD) transfer and experimental lines. They are used for the steering and profile measurement of the low energy antiproton beam that is extracted at the energy of 5.3 MeV from the AD machine. At this very low energy, the standard MWPC's are not only destructive for the beam but also perturb strongly the 2D profile measurement. These chambers are also based on technology that is outdated and in recent years have shown to be fragile and expensive to repair. For these reasons a new, low cost profile monitor, based on a Gas Electron Multiplier (GEM) detector is under development as a possible replacement of the MWPC's. This new profile monitor will enable high precision, true 2D profile measurements of the low energy antiproton beam. In this paper, we present the modification of the standard GEM detector required by our specific application and the first results of the profile monitor with antiproton beams.

THPLT008	A Beam Condition Monitor for the Experimental Areas of the LHC	linac, laser, simulation, insertion	2472
	L. Fernandez-Hernando, L. Fernandez-Hernando, C. Ilgner, A. Oh, H. Pernegger CERN, Geneva A. Macpherson PSI, Villigen T. Pritchard CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon R. Stone Rutgers University, The State University of New Jersey, Piscataway, New Jersey
	The CERN Large Hadron Collider (LHC) will store 2808 bunches per colliding beam, with each bunch consisting of 1·10¹¹ protons at an energy of 7 TeV. If there is a failure in an element of the accelerator, the resulting beam losses could cause damage not only to the machine but also to the experiments. A Beam Condition Monitor (BCM) is foreseen to monitor fast increments of fluence rate near the interaction point and, if necessary, to generate an abort signal to the LHC accelerator control to dump the beams. The system is being developed initially for the CMS experiment, but is sufficiently general to find potential applications elsewhere. Due to its high radiation hardness, CVD diamond was chosen for investigation as the BCM sensor. Various samples of CVD diamond have been characterised extensively with both a Sr-90 source and in a high intensity testbeam in order to assess the capabilities of such sensors and to study whether this detector technology is suitable for a BCM system. A selection of results from these investigations is presented.

THPLT009	Comparative Transverse Distribution Measurements between the New SPS Rest Gas Ionisation Monitor and the Wire Scanner Monitors.	linac, laser, simulation, insertion	2475
	C. Fischer, B. Dehning, J. Koopman, D. Kramer, F. Roncarolo CERN, Geneva
	During the past two years, a new Ionization Profile Monitor was installed and tested in the CERN SPS. In parallel modifications were made on various wire scanner monitors. The aim is to develop instruments performing reliable measurements of transverse beam distributions in the SPS and in the LHC, in order to control the stringent emittance preservation requirements. Measurements made with the two types of monitors were performed under various conditions of LHC type beams, ranging from a pilot bunch up to beams having in the SPS nominal distributions in bunch number, intensity and energy for injection into the LHC. The data provided by the two types of instruments are compared. In the case of discrepancies, an analysis of the possible reasons is made. The cures implemented and the improvements foreseen are discussed.

THPLT010	Limiting High Frequency Longitudinal Impedance of an Inductive Pick-up by a Thin Metallic Layer	laser, simulation, insertion, target	2478
	M. Gasior CERN, Geneva
	An Inductive Pick-Up (IPU) was developed to measure the position and current of an electron beam of the CTF3 Drive Beam Linac. The pick-up construction is similar to a wall current monitor, but the pick-up inner wall is divided into 8 electrodes, each of which forms the primary winding of a toroidal transformer. The beam image current component flowing along each electrode is transformed to a secondary winding, connected to an output. The continuity of the vacuum chamber is taken care of by a ceramic insertion surrounded by the electrodes. The insertion is titanium coated on the inside and the end-to-end resistance of the layer is chosen in such a way that within the IPU bandwidth the image current flows over the electrodes. For higher frequencies the current is conducted by the coating to limit the longitudinal impedance of the device in the GHz range. This paper describes a simple electric network model, which was used to simulate the influence of the coating and to optimize its resistance. The model is built from sections of ideal transmission lines and resistors and is suitable for SPICE simulations. Results of measurements and simulations are compared.

THPLT011	Longitudinal Loss Distribution along the LHC	laser, simulation, target, lattice	2481
	E.B. Holzer, B. Dehning CERN, Geneva
	For the design and calibration of the LHC beam loss monitoring system it is essential to have good predictions of the expected longitudinal loss distributions. For this purpose a complete and detailed aperture model of one LHC sector was compiled and included with the tracking code MAD. The positions of all beam pipe bellows are included in the model as well. Therefore, it allows investigating the loss pattern due to misalignment effects, in addition to steady beam losses (beam halo, beam-beam and beam-rest gas interactions) and orbit errors. Loss maps of halo particles originating from the betatron cleaning insertion have been created for proton and ion beams. The distribution of particle losses along the beam pipe is folded with the result of GEANT simulations of the shower development through the magnets and cold masses. They link the loss of a beam particle on the aperture to particle fluencies outside of the cryostats, where the beam loss monitors will be installed. These simulations determine the positioning of the loss monitors, the longitudinal distance one detector has to cover to achieve the required resolution as well as all calibration factors for the individual detectors. The model also serves to identify hot spots, which can limit the performance of the LHC.

THPLT012	Design of the Beam Loss Monitoring System for the LHC Ring	laser, simulation, target, lattice	2484
	E.B. Holzer, B. Dehning, E. Effinger, G. Ferioli, J.L. Gonzalez, E. Gschwendtner, G. Guaglio, M. Hodgson, V. Prieto, C. Zamantzas CERN, Geneva
	The beam loss monitoring (BLM) system of the LHC is one of the most critical elements for the protection of the LHC. It must prevent the super conducting magnets from quenches and the machine components from damages, caused by beam losses. It helps in the identification of the loss mechanism by measuring the loss pattern. Special detectors will be used for the setup and control of the collimators. Furthermore, it will be an important tool during machine setup and studies. The specification requirements of the BLM system include a very high reliability

THPLT013	Simulation of Multi-bunch Multi-turn Instabilities in High Energy Proton Rings: Algorithms and Results	laser, target, lattice, undulator	2487
	A. Koschik CERN, Geneva
	A simulation code to study collective effects in multi-bunch proton machines has been developed and applied to the CERN SPS and LHC. The 3D simulation program allows the exploration of long-range effects due to resistive-wall and HOMs in circular, elliptic and rectangular vacuum chambers also for uneven filling schemes. The code has been benchmarked with measurements in the SPS. Results obtained for LHC, including beam stability and emittance growth, are presented and discussed.

THPLT014	Coupler Structures for the LHC Beam-pipe Waveguide Mode Reflectometer	laser, target, lattice, undulator	2490
	T. Kroyer TU Vienna, Vienna F. Caspers CERN, Geneva
	The LHC reflectometer will be used to detect and localize obstacles and other kinds of discontinuities in the LHC beam screen. An important part of this device is the RF coupler element, which provides the interface between the circular beam screen and the measurement equipment. Two different scenarios of operation are considered. The first option consists in carrying out measurements during assembly by directly branching a coupler to the end of the beam screen. The other one is a permanent installation to be used in situ requiring a different kind of coupler to keep the aperture free. The goal is to achieve a reasonably well-matched spurious mode-free excitation over a 25% bandwidth for the TM01 and the T·10¹¹ mode, respectively. The fulfillment of the required features is severely complicated by space and material restrictions arising mainly from vacuum and installation constraints.

THPLT015	Accuracy of Profile Monitors and LHC Emittance Measurements	laser, target, lattice, undulator	2493
	F. Roncarolo, G. Arduini, B. Dehning, G. Ferioli, J. Koopman, D. Kramer CERN, Geneva
	The monitoring and controlling of the beam transverse emittance is essential to allow high luminosity performances in a collider operation. The profile monitors in the LHC injection chain are exploited to determine their precision. A fit strategy was developed to reduce the fitting procedure error and make it negligible compared to instrumentation errors. The method proved to be robust against non-Gaussian tails and can estimate the fraction of non-Gaussian distributed beam intensity. The procedure was applied to the 2003 SPS Wire Scanner measurements with different kind of LHC type beams. The reproducibility of the six available monitors was determined by choosing one as a reference and making synchronized measurements. Several instrumental errors were discovered and corrected to the one per cent level. The demanding small LHC transverse emittances were determined under different beam conditions in terms of intensity, bunch spacing and length in the PS Booster, PS and SPS.

THPLT016	LHC Orbit Feedback Tests at the SPS	feedback, laser, target, lattice	2496
	J. Wenninger, J. Andersson, L.K. Jensen, R.O. Jones, M. Lamont, R. Steinhagen CERN, Geneva
	The real-time orbit feedback system foreseen for the LHC will be an essential component for reliable and safe machine operation. A test setup including a number of beam position monitors equipped with the LHC acquisition and readout system have been installed in the SPS ring to perform prototyping work on such an orbit feedback. A closed loop digital feedback was implemented and tested with LHC beams on the SPS during the 2003 machine run. The feedback loop was tested successfully at up to 100 Hz. The performance of the feedback loop and of its constituents will be described.

THPLT017	Review and Comparison of Simulation Codes Modeling Electron-Cloud Build Up and Instabilities	feedback, laser, target, lattice	2499
	F. Zimmermann, E. Benedetto, F. Ruggiero, D. Schulte CERN, Geneva G. Bellodi CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon M. Blaskiewicz, L. Wang BNL, Upton, Long Island, New York Y. Cai, M.T.F. Pivi SLAC, Menlo Park, California V.K. Decyk, W. Mori UCLA, Los Angeles, California M.A. Furman LBNL/AFR, Berkeley, California A.F. Ghalam, T. Katsouleas USC, Los Angeles, California K. Ohmi, S.S. Win KEK, Ibaraki G. Rumolo GSI, Darmstadt
	Several computer codes written at various laboratories are employed for modelling the generation and the consequences of an electron cloud. We review the most popular of these programs, which simulate either the build of an electron cloud or the instabilities it produces, and we compare simulation results for identical, or similar, input parameters obtained from the various codes.

THPLT018	Electron Beam Dynamics Simulations for the Low Emittance Gun	feedback, gun, electron, target	2502
	M. Dehler, S.C. Leemann PSI, Villigen A.E. Candel ETH, Zürich
	We report on theoretical simulation performed for the development of a high brightness, field emitter based electron gun suitable for an Angstrom wavelength free electron laser\cite{LEG}. First simulations have been done with available codes in 2 1/2D and 3D for basic gun configurations showing the global and local (due to the granularity of the emitter array) effects on the emittance dilution.Design and construction started on a test setup consisting of a 100 keV electron gun with solenoidal focusing and a diagnostics module. In addition to solenoid focussing, anode shaping will be investigated in order to compensate for non-linear fields leading to space charge blow-up. For advanced simulations of field emitter based guns allowing to resolve individual emitters and to capture the influence of mechanical imperfections, a massive parallel code for 3D particle-in-cell simulations is in development. The electromagnetic field solver is fully functional and the particle tracker has been completed in its basic structures.

THPLT019	Commissioning Results of the Multi Bunch Feedback System at SLS	gun, electron, target, lattice	2505
	M. Dehler, R. Kramert, P. Pollet, T. Schilcher PSI, Villigen D. Bulfone, M. Lonza ELETTRA, Basovizza, Trieste
	Within the frame of the project for a multi bunch feedback system for the Swiss Light Source (SLS), a new family of 500 MS/s analog to digital and digital to analog conversion boards with an 8 bit resolution has been developed, containing on board MUX and DEMUX circuitry to reduce data rates to approximately 20 MS/s using up to ten Front Panel Data Port (FPDP) ports. Using six quad processor DSP boards, full bandwidth bunch by bunch feedbacks in the transverse and longitudinal planes are set up to provide bunch by bunch correction kicks with a 2 nsec resolution. We report on the hardware setup and properties as well as feedback performance in the SLS storage ring.

THPLT020	The DSP-based Betatron Tune Feedback of the Ramped 1.5 GeV Electron Storage Ring BoDo	feedback, gun, electron, target	2508
	B. Keil PSI, Villigen K. Wille DELTA, Dortmund
	The ramped storage ring BoDo is the full energy injector of the 1.5 GeV synchrotron light source DELTA. All ramped booster magnet power supplies, RF power and beam diagnostics of BoDo are handled by a distributed VME-based DSP (digital signal processor) multiprocessing system developed at DELTA. The VME DSP boards of this system are interconnected by DeltaNet, a novel reflective memory ring network. DeltaNet transmits the measurement data from each DSP board to all other boards in real-time via fibre optic links. The generic hardware and software architecture of the system allows the implementation of different kinds of global real-time feedbacks with correction rates in the range from some 100 Hz to some 10 kHz. This paper presents architecture and performance of a real-time betatron tune feedback that was implemented with the DSP system. The betatron tune is measured and corrected in both planes at a rate of typically 700 Hz for arbitrary beam optics and energy ramps of BoDo. In combination with the global Bodo orbit feedback, the tune feedback increases the performance of Bodo both as an injector and as a testbed for machine studies and newly developed accelerator components.

THPLT021	A DSP-Based Fast Orbit Feedback System for the Synchrotron Light Source DELTA	feedback, gun, electron, target	2511
	B. Keil PSI, Villigen K. Wille DELTA, Dortmund
	A DSP-based Fast Orbit Feedback (FOFB) system has been designed for the synchrotron light facility DELTA. DELTA consists of a 60 MeV linac, the ramped storage ring BoDo as full-energy injector and the 1.5 GeV storage ring Delta. BoDo and Delta have the same dipole, quadrupole and corrector magnet design, the same beam pipe design and the same BPM RF frontends, therefore BoDo was used as a testbed for the newly developed FOFB hardware and software. Using the fast corrector magnet power supplies of BoDo, the FOFB could damp orbit perturbations up to 90 Hz. The envisaged future use of the FOFB for the Delta storage ring will require either the partial or full replacement of the present slow (1 Hz bandwidth) Delta corrector power supplies, or additional fast power supplies with dedicated FOFB corrector magnets. A first test of the FOFB in Delta for local orbit stabilization at one beamline is in preparation. This paper presents the results of a successful test of the FOFB at BoDo, where it achieves a correction rate of 4 kHz for a global SVD-based feedback in both planes. The FOFB is based on the "DeltaDSP" VMEbus DSP boards that are also used for the BoDo betatron tune feedback.

THPLT022	The Generic VME PMC Carrier Board: A Common Digital Hardware Platform for Beam Diagnostics and Feedbacks at PSI	gun, target, lattice, undulator	2514
	B. Keil, C. Buehler, P.-A. Duperrex, U. Greuter, R. Kramert, P. Pollet, V. Schlott, N. Schlumpf, P. Spuhler PSI, Villigen
	Rapid progress in digital electronics allows digitization of monitor signals at a very early stage of the signal processing chain, providing optimum performance and maximum flexibility for today's accelerator instrumentation. While the analog front-ends of such systems are usually specific for each monitor type, the subsequent digital part of the processing chain can be unified for many different measurement tasks. The "VME generic PMC Carrier board" (VPC) was developed to achieve this unification at the PSI electron and proton accelerator diagnostics and fast data acquisition and feedback systems. The core of the VME64x board consists of two Virtex2Pro FPGAs with two PowerPCs each, a floating point DSP and RAM. The FPGAs can acquire and process measurement data from the VMEbus P0/P2 connectors or from two application-dependent PMC mezzanine modules. Two 2 GBaud fibre optics transceivers may also be used to aquire or distribute measurement data. Envisaged applications include digital beam position (DBPM) and current monitors for proton beams, data processing for a muon decay experiment, and general beam diagnostics as well as global feedbacks at SLS accelerators and beamlines.

THPLT023	The Use of Photon Monitors at the Swiss Light Source	photon, gun, target, lattice	2517
	J. Krempasky, M. Böge, T. Schilcher, V. Schlott, T. Schmidt PSI, Villigen
	The photon beam position monitors (PBPM) in a synchrotron radiation facility are important tools for beam-line and machine diagnostics since they deliver position and angle information directly from the radiation source point. In the last two years a number of PBPMs have been installed and commissioned at the Swiss Light Source (SLS). Their readouts have been systematically studied and the results have been correlated with data from the digital beam position monitor (DBPM) system. It turns out that the PBPMs help understanding the influence of insertion device gap changes on photon beam position and thus on photon flux and/or energy resolution near the beam-line experimental stations. In addition to the global fast orbit feedback (FOFB), a local slow feedback based on PBPM data has been implemented to remove the remaining systematic effects of the DBPM system and to stabilize the photon beam to a micron level at the experimental station.

THPLT024	Commissioning and Operation of the SLS Fast Orbit Feedback	photon, gun, target, lattice	2520
	T. Schilcher, M. Böge, B. Keil, P. Pollet, V. Schlott PSI, Villigen
	The SLS Fast Orbit Feedback (FOFB) was successfully commissioned in 2003. Since November 2003 it runs during user operation of the accelerator. Taking into account 72 Digital Beam Position Monitors (DBPMs), the FOFB applies SVD-based global orbit corrections for 72 horizontal (x) and 72 vertical (y) correctors at a rate of 4 kHz, compared to ~0.5 Hz for the Slow Orbit Feedback (SOFB) that was used so far. While the SOFB was important for the elimination of orbit drifts due to temperature changes and slowly moving insertion device (ID) gaps, the FOFB is also able to damp orbit oscillations that are caused by fast changes of ID gaps or magnets, by ground and girder vibrations, 3 Hz booster crosstalk and power supply noise. This report presents experience from commissioning and user operation of the FOFB.

THPLT025	Using Visible Synchrotron Radiation at the SLS Diagnostics Beamline	gun, target, lattice, undulator	2523
	V. Schlott, M. Dach, Ch. David, B. Kalantari, M. Pedrozzi, A. Streun PSI, Villigen
	A diagnostics beamline has been set-up at the BX05 bending magnet of the SLS storage ring. It is equipped with a standard bending magnet front end, including two photon beam position monitors (PBPM) for determination of photon beam angle and position as well as a pinhole array monitor for online monitoring of beam size. The visual part of the dipole radiation is transported to an optical lab, where the temporal profile of the storage ring bunches can be measured with a minimal time resolution of 2 ps using a dual sweep, synchrocan streak camera. Simultaneously, beam size and coupling can be measured at 1.8 keV radiation energy with a zome plate monitor overcoming diffraction limitations. This paper describes the beamline design and summarizes the first experimental results.

THPLT026	Beam Profile Measurements at PETRA with the Laserwire Compton Scattering Monitor	positron, laser, gun, target	2526
	T. Kamps BESSY GmbH, Berlin K. Balewski, H.-C. Lewin, S. Schreiber, K. Wittenburg DESY, Hamburg G.A. Blair, G. Boorman, J. Carter, F. Poirier Royal Holloway, University of London, Surrey S.T. Boogert UCL, London T. Lefevre CERN, Geneva
	The vertical beam profile at the PETRA positron storage ring has been measured using a laserwire scanner. A laserwire monitor is a device which can measure high brilliant beam profiles by scanning a finely focused laser beam non-invasively across the charged particle beam. Evaluation of the Compton scattered photon flux as a function of the laser beam position yields the transverse beam profile. The aim of the experiment at PETRA is to obtain the profile of the positron beam at several GeV energy and several nC bunch charge. Key elements of laserwire systems are currently being studied and are described in this paper such as laser beam optics, a fast scanning system and a photon calorimeter. Results are presented from positron beam profile scans using orbit bumps and a fast scanning scheme.

THPLT027	Optical Transition Radiation Based Beam Diagnostics at the BESSY Synchrotron Radiation Source and FEL Accelerators	positron, gun, target, lattice	2529
	T. Kamps, K. Holldack, P. Kuske BESSY GmbH, Berlin
	Optical Transition Radiation (OTR) based diagnostics tools are widely used in linear accelerators to measure beam parameters like transverse beam size and emittance. Design ideas for OTR stations in the linac section of the BESSY FEL facility are presented. Several key components will be tested in the transfer lines of the BESSY storage ring. Furthermore a novel type of OTR monitor is introduced which enables the measurement of the transverse overlap of seed laser and electron beam in the undulator sections of the linac based FEL facility. Here a special radiator screen will be used allowing simultaneous imaging of both beams in the same optical readout channel.

THPLT028	High Precision Cavity Beam Position Monitor	positron, gun, target, lattice	2532
	A. Liapine, H. Henke TET, Berlin
	A cavity beam position monitor is proposed for measuring the beam deflection in the TESLA energy spectrometer. The precision of the measurement has to be better than 1 micrometer. A slotted cavity is chosen as pick-up in order to reject the background signals and enhance the precision and the dynamic range of the monitor. The paper gives the design overview for two prototypes with operating frequencies of 1.5 GHz and 5.5 GHz, respectively. The results obtained on the test bench with direct conversion electronics are presented. A resolution of about 100 nm was achieved.

THPLT029	Parallel Particle in Cell Computations with GdfidL	positron, gun, target, lattice	2535
	W. Bruns WBFB, Berlin
	The electromagnetic field solver GdfidL has been extended to compute with free moving charges. For computing in parallel, GdfidL partitions the computational volume in many small subvolumes. Each processor computes the electromagnetic field in its part of the whole volume. In addition to the normal field update equations, the movement of the particles must be computed from the Lorentz-force, and the convection current due to the moving charges must be computed and be used to change the electric field near the particle. For each particle, these computations are performed by the processor which is responsible for the volume where the particle is in. Details of the parallel implementation of the used algorithm, Particle in Cell, are given.

THPLT030	A Novel Device for Non-intersecting Bunch Shape Measurement at the High Current GSI-Linac	positron, gun, target, lattice	2538
	P. Forck, C. Dorn, M.H. Herty, P. Strehl GSI, Darmstadt V. Peplov RAS/INR, Moscow S. Sharamentov ANL, Argonne, Illinois
	Due to the high current of heavy ions accelerated at the UNILAC at GSI, non-intersecting beam diagnostics are mandatory. For bunch length and bunch structure determination in the range of 0.3 to 5 ns a novel device has been realized. It uses the time spectrum of secondary electrons created by atomic collisions between beam ions and residual gas molecules. These electrons are accelerated by an electric field of 400 V/mm toward an electro-static energy analyzer. The analyzer is used to restrict of the effective source region. Then the electrons are deflected by an rf-resonator running in phase with the acceleration frequency (36 or 108 MHz) to transform the time spectrum into spatial separation. The detection is done with a multi-channel plate equipped with a phosphor screen and observed by a digital CCD camera. The achieved time resolution is at least 50 ps, corresponding to 2 degree of rf frequency. The general layout of the device and first results will be presented.

THPLT031	Comparison of Rate Equation Models for Equilibrium Beam Parameters	positron, gun, lattice, wiggler	2541
	R.W. Hasse, O. Boine-Frankenheim GSI, Darmstadt
	We calculate equilibrium beam parameters from the counteraction of intrabeam scattering (IBS), electron cooling (EC) and target interaction for typical beams in the GSI cooler storge ring ESR and in the proposed HESR. This work is complementary to kinetic modeling efforts at GSI. We developed an easy to use simulation tool that includes various models for the EC rates and the IBS rates, averaged of the detailed ring lattices. The obtained scaling of the equilibrium parameters with beam current and energy are compared with existing experimental data from the ESR and with kinetic simulation results for the HESR.

THPLT032	Computer Controlled Beam Diagnostics for the HICAT Facility	positron, gun, lattice, wiggler	2544
	M. Schwickert, A. Peters GSI, Darmstadt
	A set of 93 diagnostic devices for beam diagnostics in the heavy ion cancer therapy facility (HICAT) at the university hospital in Heidelberg is currently under development at GSI. For the HICAT facility that is presently under construction, all beam diagnostic devices are fully computer controlled and allow an automated detection of all relevant beam parameters. The HICAT rasterscan method with active variation of intensity, energy and beam size requires the exact knowledge of the time resolved and spatial structure of the ion beam. An overview of the integrated devices is presented and the intensity measurement of both, the DC and AC beam in the different parts of the accelerator facility are reviewed. Additionally, the timing and control of the diagnostic devices are described.

THPLT033	The Heavy Ion Gantry of the HICAT-facility	ion, positron, gun, lattice	2547
	U. Weinrich, R. Fuchs GSI, Darmstadt P. Emde MAN Technologie AG, Mainz
	The Heavy Ion Cancer Therapy Project HICAT at the University Hospital of Heidelberg is under construction. One unique feature of the treatment facility is the first heavy ion gantry in the world. The Gantry will allow the patient treatment with different ion species up to 430 MeV/u with full geometrical flexibility. This functionality has to be maintained for up to 300 000 rotations over the envisaged life cycle of 15 years. GSI has taken the responsibility to coordinate the design and construction of all the different required components. At the time of the conference the design will be finished and the construction started. The contribution will report on challenging construction items like the survey and alignment strategy, safety aspects, flexibility of the ion optics. In order to gain confidence on the principle a test bench with the last part of the gantry was already mounted in a fixed manner at GSI and beam measurements were performed. The results of these tests will also be reported.

THPLT034	Implementation of Higher Order Moments for Beam Dynamics Simulation with the V-Code	ion, positron, gun, lattice	2550
	W. Ackermann, T. Weiland TEMF, Darmstadt
	Based on the moment approach V-Code is implemented to simulate charged particle beam dynamics in linear accelerators. Its main aim is to perform elementary studies in those cases when the beam can be considered as a whole and thus making the motion of individual particles negligible in the overall view. Therefore an ensemble of particles can be well described by the moments of its phase-space distribution and the regarded order influences naturally the achievable accuracy as well as the computational effort. Since the well known moment equations generally are not closed, a technique to limit the number of involved moments has to be applied. So far all moments up to the second order have been considered whereas higher order moments are truncated. As a further step towards higher accuracy the influence of higher order moments has to be investigated. For this reason additional third-order equations are implemented into the V-Code and the achieved results are compared with previous second-order-based ones as well as with higher order approximations.

THPLT035	Development of a 3D-Gun-Code based on a Charge Conserving Algorithm	ion, positron, electron, simulation	2553
	E. Gjonaj, J. Mudiganti, T. Weiland TEMF, Darmstadt
	Recent efforts in the development of electron sources are aiming at high intensity electron beams, beyond the limitations posed by space-charge effects in conventional guns. Field emitter arrays, multi-beam and sheet-beam guns are a few examples of emerging technology, which require an accurate characterization of the limiting current in complicated 3D-geometry. The newly developed gun code at the Technische Universität Darmstadt, implements a novel approach to the numerical simulation of space-charge-limited electron emission, which is based on the local conservation of charge for arbitrary cathode surfaces. It is shown that, imposing exact charge conservation using the CAD-data of the geometry eliminates the spurious oscillations in the charge density, which typically arise when the piecewise-planar diode approximation is applied in the simulation. The accuracy of this approach is demonstrated in the validation study of a spherical diode and in the large-scale simulation of a Traveling Wave Tube amplifier.

THPLT036	New Discretization Scheme for Wake Field Computation in Cylindrically Symmetric Structures	ion, positron, electron, simulation	2556
	R. Hampel, T. Weiland, I. Zagorodnov TEMF, Darmstadt
	Collective effects due to wake fields are a limiting factor in almost every new front line accelerator. Since the early 80's computer codes such as TBCI and MAFIA have been developed for computing wake fields in realistic accelerator structures. With the advent of linear collider studies and small wavelength FEL projects these codes had to face a severe limitation. For the very short bunches in these new accelerators combined with the need for an analysis of very long sections the discrete dispersion became a serious drawback. This effect of having only discrete field values rather than continous ones can be overcome by special algorithms such as semi-implicit integrators as used e.g. in the wake field code ECHO. In this paper we present a new explicit approach which combines the advantage of explicit algorithms (fast) with the absence of dispersion in beam direction.

THPLT037	Investigation of Numerical Noise in PIC-Codes	ion, positron, electron, simulation	2559
	S. Schnepp, S. Setzer, T. Weiland TEMF, Darmstadt
	For a detailed analysis of the dynamics of space charge dominated beams a combination of Particle-in-Cell methods with efficient FDTD schemes is widely used. Besides the calculation of the forces acting on the particles the interaction of the beam itself with the surrounding geometries is taken into account. A drawback of this method is its sensitivity to numerical noise in the spectral range nearby the grid cutoff frequency. In this paper we will present results of detailed studies of the impact of the bunch shape on the level of the numerical noise. Furthermore an a priori scheme for efficient noise suppression is derived which does not affect the FDTD update algorithm.

THPLT038	The Synchrotron Radiation Interferometer using Visble Light at DELTA	ion, positron, synchrotron, simulation	2562
	U. Berges, K. Wille DELTA, Dortmund
	Synchrotron radiation sources such as DELTA, the Dortmund electron accelerator, rely on a monitoring system to measure the beam size and emittance with sufficient resolution. The resolution limits of the different types of optical synchrotron light monitors at DELTA have been investigated. The minimum measurable beam size with the standard synchrotron light monitor using visible light at DELTA is appr. 80 μm. Due to this limitation an interferometer was built up and tested using the same beamline in the visible range. A minimum measurable beam size of appr. 8 μm could be obtained, which gives an increased resolution of one order of magnitude with the new system.

THPLT039	SVD Based Orbit Correction Incorporating Corrector Limitations at DELTA	ion, positron, synchrotron, simulation	2565
	M. Grewe, P. Hartmann, G. Schmidt, K. Wille DELTA, Dortmund
	Singular Value Decompostion (SVD) of the orbit response matrix has become an invaluable tool for orbit correction at storage rings worldwide. SVD based orbit correction has now been realised at DELTA, a 1.5 GeV electron storage ring. However, due to special orbit demands at DELTA and possibly by magnetic imperfections within the storage ring, we frequently have to face corrector limitations during the process of orbit correction. This work focuses on presenting an analytic algorithm on how to treat these limitations when seeking for an optimal SVD based orbit correction. In contrast to previously published methods, this approach is fairly easy to implement and does not afford an numerical solver. Concepts and results will be presented.

THPLT041	Beam Test Stand of the RFQ-drifttube-combination for the Therapy Center in Heidelberg	positron, synchrotron, simulation, lattice	2568
	A. Bechtold, M. Otto, U. Ratzinger, A. Schempp, E. Vassilakis IAP, Frankfurt-am-Main B. Schlitt GSI, Darmstadt
	A beam test stand for the Heidelberg medicine RFQ has been installed at the IAP in Frankfurt. The installation consists of a 8 keV/u H⁺ duoplasmatron ion source, the 400 keV/u RFQ itself and several diagnostic elements comprising a slit-grid emittance measurement system for scanning the transverse beam profile and a bending magnet for measuring the longitudinal beam properties. The test installation will be described in detail, first measurements will be presented and compared to corresponding beam dynamic simulations.

THPLT042	Automated Orbit Control for the HERA ep Collider	positron, synchrotron, simulation, lattice	2571
	S.W. Herb, P.K. Bartkiewicz, F. Brinker, J.M. Maass DESY, Hamburg
	Successful operation of the HERA electron-proton collider requires maintaining stable orbits during the typically 12 hour luminosity runs, as well as during the fill and acceleration procedures. The primary sources of orbit errors for the electron ring are the interaction region magnets, whose support structures are integrated with the experimental detectors and susceptible to thermal and magnetic effects. The orbit correction algorithms are designed to correct these effects locally, while operating with somewhat reduced sensitivity on error sources in the rest of the ring. We describe the correction system and our operating experience.

THPLT043	Development of a New Orbit Measurement System	positron, synchrotron, simulation, lattice	2574
	O. Kaul, F. Brinker, R. Neumann, R. Stadtmüller DESY, Hamburg
	Since DORIS III became a dedicated source for synchrotron radiation in 1993, the demands of the synchrotron-light-users concerning the beam position stability have permanently increased.In order to improve this stability, different measures have been adopted, all with success. The vacuum chambers have been renewed, since they were the source of quadrupole movement, which caused strong horizontal orbit distortion. In 2003 a new orbit position control was implemented, based on the ?Singular Value Decomposition? method. The position information comes from synchrotron light monitors, installed in the beam-lines, and from the orbit measurement system, which operates with a maximal measurement rate of 5Hz and a spatial resolution not less than 20μm. To satisfy the requirements for beam-position stability, the orbit measurement system has been further developed. The test stage is nearly finished and the new system will be installed soon. The orbit measurement rate will exceed 250Hz und the spatial resolution will be less than 2μm. In addition beam oscillations of up to 20Hz can be damped.

THPLT044	Measurement of the Transverse Coherence of the TTF Free Electron Laser	undulator, positron, synchrotron, radiation	2577
	R. Ischebeck, M. Tonutti RWTH, Aachen J. Feldhaus, E. Saldin, E. Schneidmiller, K. Tiedtke, R. Treusch DESY, Hamburg C. Gerth CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire P. Schmüser Uni HH, Hamburg M.V. Yurkov JINR, Dubna, Moscow Region
	The transverse coherence is important for many applications of a free electron laser (FEL). It depends on the inner structure of the electron bunch in the undulator, which is difficult to measure. It is therefore essential to determine the coherence properties of the FEL radiation directly. The coherence of the vacuum ultraviolet FEL at the TESLA Test Facility has been measured by recording the diffraction pattern of a double slit and measuring the visibility of the interference fringes. The experimental near field diffraction pattern is compared with a numerical model, taking into account the formation of the FEL radiation, the Fresnel diffraction in the near field zone and effects of the experimental set-up. Diffraction patterns have been recorded at various undulator lengths to measure the evolution of the transverse coherence along the undulator. This is compared to the expected evolution of the transverse radiation modes.

THPLT045	A more Accurate Approach to Calculating Proton Bunch Evolution under Influence of Intra-beam Scattering in a Storage Ring.	undulator, positron, synchrotron, radiation	2580
	I.V. Agapov, F.J. Willeke DESY, Hamburg
	Some perturbations of discrete nature are known to influence the performance of a proton storage ring, contributing to parasitic background, decay of beam currents and bunch tail buildup. Such are, for example, intra-beam scattering and residual gas scattering .These processes are to a big extent described by existing analytical theory. The latter, employing a large amount of averaging, usually neglects effects arising from system nonlinearity. So, the motion of tail particles in the presence of a sufficiently nonlinear RF voltage under influence of intra-beam scattering strongly deviates from the average across the bunch and the analytical approach seems inadequate for it. To overcome this situation we have developed more accurate numerical methods for calculations of bunch evolution under influence of a rather broad class of jump-like perturbations. Here we present the computational algorithms and their application to assessment of coasting beam and proton background in HERA-p.

THPLT046	The Synchrotron Radiation Beamline at TTF2	positron, radiation, scattering, simulation	2583
	O. Grimm, S. Casalbuoni, L. Fröhlich, O. Peters, J. Rossbach DESY, Hamburg
	The VUV-FEL at DESY, Hamburg, will require novel techniques to characterize the longitudinal charge distribution of the electron bunches that drive the free-electron laser. Conventional methods are inadequate at the short bunch lengths that will be obtained. One technique under study uses coherent far-infrared radiation to reconstruct the bunch shape through Fourier analysis of the spectrum. In a first step, a beam line to guide both far-infrared (50-1000 um) and optical synchrotron radiation from one of the bunch compressor magnets of the linear accelerator to a diagnostic station outside of the controlled area is currently under construction. It will also allow a comparison between streak camera and far-infrared measurements for features on length scales above some 100 um (the streak camera resolution). Later, infrared techniques extending to shorter wavelengths, i.e. to shorter bunch lengths, will also be used further downstream the accelerator, employing synchrotron, transition and undulator radiation. The beam line design, measurement principle and first measurements will be presented.

THPLT047	Beam Position Monitor Development for the IThemba LABS Cyclotron Beamlines	positron, radiation, scattering, simulation	2586
	J. Dietrich, I. Mohos FZJ/IKP, Jülich A.H. Botha, J.L. Conradie, J.L.G. Delsink, P.F. Rohwer IThemba Labs, Somerset West
	In cooperation of iThemba LABS (South Africa) and Forschungszentrum Juelich the specification of a sensitive tunable rf narrowband beam position monitor system for cyclotron beamlines has been elaborated. iThemba LABS developed and manufactured the four section stripline monitor chamber. The monitor electronics were developed in the Forschungszentrum Juelich-IKP. The electronics consisting of an RF signal processing module (BPM-RF) and a data acquisition and control module (BPM-DAQ) sequentially processes and measures the monitor signals and deliver via serial network calculated horizontal and vertical beam position data. First measurements with cyclotron beam has been performed in the iThemba LABS in November 2003. Changed beam position due to changing different cyclotron parameters could be studied with high accuracy. The resolution of the beam position measurement was better than 0.1 mm with beam currents down to 0.0005 mA.

THPLT048	Progress in 3D Space-charge Calculations in the GPT Code	positron, radiation, scattering, simulation	2589
	G. Pöplau, U. Van Rienen Rostock University, Faculty of Engineering, Rostock M.J. de Loos PP, Soest S.B. van der Geer TUE, Eindhoven
	The mesh-based 3D space-charge routine in the GPT (General Particle Tracer, Pulsar Physics) code scales linearly with the number of particles in terms of CPU time and allows a million particles to be tracked on a normal PC. The crucial ingredient of the routine is a non-equidistant multi-grid Poisson solver to calculate the electrostatic potential in the rest frame of the bunch. The solver has been optimized for very high and very low aspect ratio bunches present in state-of-the-art high-brightness electron accelerators. In this paper, we explore the efficiency and accuracy of the calculations as function of meshing strategy and boundary conditions.

THPLT050	End to End Simulations of the RX2 Beam Transport	positron, radiation, scattering, simulation	2592
	N. Pichoff, J.-M. Lagniel CEA/DAM, Bruyères-le-Châtel
	RX2 is a project aiming to produce a high flux of X-rays for radiography purpose. We proposed an RF linac using a DC photo-injector producing 20 bunches with 100nC each at 352 MHz. The beam is then injected in 4 RF superconducting cavities and accelerated to 40 MeV. It is then focused on a target producing X-rays. Here is presented the design, the specificities, and the beam simulations from the cathode to the target by coupling 2 multiparticle codes : PARMELA and PARTRAN.

THPLT051	End to End Multiparticle Simulations of the AIRIX Linac	positron, radiation, scattering, simulation	2595
	N. Pichoff, A. Compant La Fontaine CEA/DAM, Bruyères-le-Châtel
	AIRIX is a working 3 kA, 20 MeV induction accelerator. It has been designed with an enveloppe code : ENV. A new set of multiparticle codes (PBGUNS, MAGIC, PARMELA and PARTRAN) has been used recently to simulate the beam transport with an higher accuracy especially taking into account the field non-linearities. A dedicated space-charge routine has been written. The calculation results have been compared to experimental measurements.

THPLT052	Measurement of Relative Gas Chamber Pressure in Narrow Straight Section Vacuum Vessels by Observing Gas Bremstrahlung	vacuum, positron, radiation, scattering	2598
	G.A. Naylor, B. Joly, D. Robinson ESRF, Grenoble
	The measurement of gas pressure inside long, small cross section, vacuum vessels is difficult due to the distance between the centre of the vacuum vessel and vacuum gauges (leading to a low vacuum conductance). Following initial chamber installation, significant out-gassing is observed leading to a significant pressure bump within the chamber. A modified beam loss detector has been developed in order to monitor the gamma radiation produced by the collision of the 6GeV electrons in the storage ring with residual gas atoms. The narrow beam of gamma radiation is intercepted at various points by high Z materials in the beam line front-end allowing a radiation shower to be detected outside the vacuum vessel proportional to the gas pressure in the corresponding storage ring straight section. Various locations are considerred and results shown.

THPLT053	Fast Orbit Feedback Developments at ELETTRA	vacuum, feedback, positron, radiation	2601
	D. Bulfone, R. De Monte, M. Ferianis, V. Forchi', M. Lonza ELETTRA, Basovizza, Trieste
	A number of fast local orbit feedback stations are being sequentially installed at ELETTRA to improve the stability of the electron beam at the Insertion Device source points. They rely on Beam Position Monitors equipped with digital detector electronics that provides high precision and readout rate. The local feedback stations will be integrated in a fast global orbit feedback system, which is the goal of the ongoing developments. The performance and the operational experience gained with the local feedback systems are presented together with the planned road map towards the global system.

THPLT054	Emittance Diluition due to 3D Perturbations in RF Photoinjectors.	vacuum, feedback, positron, radiation	2604
	M. Quattromini, L. Giannessi, C. Ronsivalle ENEA C.R. Frascati, Frascati (Roma)
	The predictions from different simulation codes are compared to investigate the effects of non axis-symmetric conditions, fluctuations in cathode's quantum efficiency and other sources of dishomogeneities in the performances of a typical RF photoinjector. The layout includes a RF gun and a focusing solenoid in a configuration aimed at minimizing the emittance growth due to space charge effects.

THPLT055	Longitudinal Phase Space Characterization of the CTF3 Beam with the RF Deflector	vacuum, feedback, positron, radiation	2607
	D. Alesini, C. Biscari, A. Ghigo, F. Marcellini INFN/LNF, Frascati (Roma) R. Corsini CERN, Geneva
	The characterization of the longitudinal phase space of the CTF3 beam is an important item for tuning all machine parameters and increase the 30 GHz power production. By means of an RF deflector and a dispersive system the longitudinal phase space can be completely characterized. In this paper we present the simulation of the measurement and the mechanical layout of the full system.

THPLT056	Horizontal Instability and Feedback Performance in DAFNE e⁺ Ring	vacuum, feedback, radiation, scattering	2610
	A. Drago INFN/LNF, Frascati (Roma)
	In DAFNE, after the 2003 shutdown for the installation of FINUDA, a strong horizontal multibunch instability was found to limit the positron beam current at the level of ~450 mA. We have performed transverse grow-damp measurements in order to estimate the instability growth rates as well as the feedback damping rates for each bunch at different beam currents and to evaluate the tune shift along the bunch train. In particular, a strong dependence of oscillation amplitudes on the relative position of the bunch in the train has been observed. In this paper we describe the setup for multibunch oscillation amplitude recording, discuss the transverse feedback performance and summarize some observations on the transverse instability. The feedback rises the threshold by about a factor of two, depending on the machine configuration.

THPLT057	An RF Deflector Design for 6d Phase Space Characterization of the Sparc Beam	vacuum, feedback, radiation, scattering	2613
	C. Vaccarezza, D. Alesini INFN/LNF, Frascati (Roma) M. Amadei, P. Cascavola, A. Mostacci, L. Palumbo Rome University La Sapienza, Roma J. Rosenzweig UCLA, Los Angeles, California
	The characterization of the longitudinal and transverse phase space of the beam provided by the SPARC photoinjector is a crucial point to establish the performance quality of the photoinjector itself. By means of an RF deflector and a dispersive system, the six dimensional beam phase space can be analyzed. A five cell SW aluminum prototype of the SPARC RF deflector has been realized and tested. We report in this paper the design issues together with the RF measurement results. The simulation results of the 6D phase space reconstruction of the SPARC beam are also presented.

THPLT058	Commissioning of the OTR Beam Profile Monitor System at TTF/VUV-FEL Injector	vacuum, feedback, scattering, cyclotron	2616
	A. Cianchi, L. Catani, E.C. Chiadroni INFN-Roma II, Roma M. Castellano, G. Di Pirro INFN/LNF, Frascati (Roma) K. Honkavaara DESY, Hamburg M. Raparelli Università di Roma II Tor Vergata, Roma
	The TESLA Test Facility (TTF) linac at DESY is being extended to an energy of 1 GeV to drive a new Free Electron Laser facility (VUV-FEL)with wavelengths between 100 nm and 6 nm.Beam profile monitors based on optical transition radiation (OTR) are one of the most important electron beam diagnostics tools. The OTR imaging system is designed to measure the transverse beam size and shape with a resolution down to 10 um. The images are digitized by CCD cameras. A network structure allows a simpler topology to connect the large number of cameras (24).This paper considers the commissioning of the OTR beam profile monitors during the first running period of the injector in spring 2004.

THPLT059	Design Study of a Movable Emittance Meter Device for the SPARC Photoinjector	vacuum, emittance, feedback, scattering	2619
	A. Cianchi, L. Catani INFN-Roma II, Roma M. Boscolo, M. Castellano, A. Clozza, G. Di Pirro, M. Ferrario, D. Filippetto, V. Fusco INFN/LNF, Frascati (Roma) L. Giannessi, L. Picardi, M. Quattromini, C. Ronsivalle ENEA C.R. Frascati, Frascati (Roma)
	Preliminary studies of the SPARC rf gun are planned to obtain an accurate analysis and optimization of the emittance compensation scheme, measuring the beam emittance evolution downstream the RF gun with an appropriate diagnostic system. Since with a space charge dominated beam the use of the quad-scan method is not possible a 1D pepper-pot method will be used. A mask with narrow slits will be mounted on a movable support, spanning a 1.5 m meters region to measure the emittance in several positions and reconstruct its behavior in the post gun section. Numerical simulations of the measurement process, mainly based on PARMELA and TREDI, are used to estimate the achievable accuracy and to optimize the experimental setup. Wake field effects induced by the beam propagation through the long bellows have been also investigated with HOMDYN. Based on these simulations the design of the apparatus, called emittance-meter, has been realized and is under construction at LNF.

THPLT060	An Automatic Beam Characterization Instrument for Proton Therapy Applications	vacuum, emittance, feedback, scattering	2622
	D. Giove, C. De Martinis, M. Mauri INFN/LASA, Segrate (MI) C. Cirrone, G. Cuttone INFN/LNS, Catania
	The characterization in the transverse plane of the beam is a fundamental step in the design of a proton therapy facility. In this paper we will describe an automatic system able to measure the transverse profiles of the proton beam used in the Catana facility at LNS-Catania. The system has been designed as an autonomous equipment able to acquire optical images of the beam (after an interaction with a converter) and to elaborate them to extract the relevant parameters. The equipment may be interfaced to the rest of the control system of the facility and to the operator interface to provide high level control and monitoring tools. Operational experience will be discussed and the results so far obtained will be outlined.

THPLT061	Development of a Multibunch Photo-cathode RF Gun System	vacuum, gun, emittance, cathode	2625
	J. Urakawa, M. Akemoto, S. Araki, H. Hayano, M. Kuriki, T. Muto, N. Terunuma, Y. Yamazaki KEK, Ibaraki M.K. Fukuda, K. Hirano, M. Nomura, M. Takano NIRS, Chiba-shi
	A multibunch photo-cathode RF gun system has been developed as a electron source for the production of quasi-monoenergetic X-rays based on inverse Compton scattering. This system consists of a photocathode rf gun, a cathode system, a laser system, beam diagnostic sections, and beam dump line. The gun produces 100 bunches with a 2.8ns bunch spacing and 5nC bunch charge. We will report on the RF gun system with 4 bending dipoles of a chicane which makes the laser injection to the cathode with perpendicular angle possible.

THPLT062	Alternating-phase-focused Linac for an Injector of Medical Synchrotrons	vacuum, linac, gun, emittance	2628
	Y. Iwata, T. Fujisawa, T. Furukawa, T. Kanai, M. Kanazawa, N. Kanematsu, M. Komori, S. Minohara, T. Murakami, M. Muramatsu, K. Noda, M. Torikoshi, S. Yamada NIRS, Chiba-shi Y.F. Fujii, T. Mitsumoto, H. Tsutsui SHI, Tokyo T. Fujimoto, H.O. Ogawa, S. Shibuya AEC, Chiba V. Kapin MEPhI, Moscow
	Tumor therapy using Heavy Ion Medical Accelerator in Chiba (HIMAC) has been made over ten years at National Institute of Radiological Sciences (NIRS). Due to the successful clinical results, the project on developing compact medical accelerators for the tumor therapy has been started. To design these compact facilities, the size of a linac as well as the construction and operation costs is important. To satisfy these requirements, we propose Alternating-Phase-Focused (APF) linac using an Interdigital H-mode cavity. Since the axial and radial focusing of beam is made just with the acceleration rf field, no additional focusing elements is needed for the APF linac. This feature would make the costs lower than those of conventional linacs. The practical design of the APF linac will be presented.

THPLT063	Proposal of Carbon-beam Facility for Cancer Therapy in Japan	vacuum, gun, emittance, cathode	2631
	K. Noda, T. Fujisawa, T. Furukawa, Y. Iwata, T. Kanai, M. Kanazawa, N. Kanematsu, A. Kitagawa, Y. Kobayashi, M. Komori, S. Minohara, T. Murakami, M. Muramatsu, S. Sato, Y. Sato, S. Shibuya, E. Takada, O. Takahashi, M. Torikoshi, E. Urakabe, S. Yamada, K. Yoshida NIRS, Chiba-shi
	Since 1994, the clinical trial at HIMAC has been successfully being progressed and more than 1,700 patients have treated with carbon ions. Owing to the good result of HIMAC, several medical groups in Japan have strongly required the carbon therapy facility. Based on the development of accelerator and the irradiation technologies for 10 years, therefore, we started to design a carbon therapy facility in Japan. The accelerator complex for the facility consists of two ECR ion sources with permanent magnets, an injector linac cascade (RFQ+IH) with the energy of 4 MeV/n, a synchrotron ring with the maximum energy of 400 MeV/n and beam delivery system for three treatment rooms. The R&D for the new facility has been already approved and will be started from April 2004. We will describe the conceptual design of the new facility.

THPLT064	Enhancement of Laser Power from a Mode Lock Laser with an Optical Cavity	laser, vacuum, gun, emittance	2634
	M. Nomura, K. Hirano, M. Takano NIRS, Chiba-shi S. Araki, Y. Higashi, T. Taniguchi, J. Urakawa, Y. Yamazaki KEK, Ibaraki Y. Honda, N. Sasao, K. Takezawa Kyoto University, Kyoto H. Sakai ISSP/SRL, Chiba
	We have developed a laser-wire beam monitor to measure a beam profile in the KEK/ATF damping ring. This monitor is based on the inverse Compton scattering with a thin wire of the laser. The laser-wire is produced with a Fabry-Perot optical cavity in which laser power from a CW laser is stored and enhanced up to 1000 times. We have a plan to increase a gamma ray flux by using a pulsed laser instead of the CW laser. There are many applications for such a high flux gamma ray, e.g. medical use, transmutation and so on. We have done a test experiment of laser pulse stacking with a mode lock laser where wavelength is 1064 nm, repetition rate 357MHz, pulse width 7psec(FWHM) and a 42 cm long Fabry-Perot optical cavity. The experimental results show that laser power in the optical cavity can be enhanced by laser pulse stacking.

THPLT065	Study of Multiturn Injection at HIMAC Synchrotron	laser, vacuum, injection, gun	2637
	T.H. Uesugi, T. Furukawa, T. Naruse, K. Noda NIRS, Chiba-shi T. Fujimoto, S. Shibuya AEC, Chiba
	In the multiturn injection method at the HIMAC synchrotron, a collapsing speed of the bump orbit was decreased from 200 to 350 microseconds in order to obtain higher intensity beam. The injection line was readjusted to satisfy the optimum condition of multiturn injection method. Furthermore, COD correction and bump-orbit optimization were carried out. On the other hand, in order to prevent the resonance by tune shift and to keep the beam intensity constant, tune survey was carried out. While vertical tune is adjusted, we propose that the method to reduce beam loss after injection by expanding vertical beam size by means of the RF-knockout. This paper describes the improvement of injection at HIMAC synchrotron.

THPLT066	Commissioning of 150MeV FFAG Synchronisation	laser, vacuum, gun, emittance	2640
	Y. Yonemura, M. Matoba Kyushu University, Fukuoka M. Aiba, M. Sugaya University of Tokyo, Tokyo S. Machida, Y. Mori, A. Muto, J. Nakano, C. Ohmori, I. Sakai, Y. Sato, A. Takagi, T. Yokoi, M. Yoshii, M. Yoshimoto, Y. Yuasa KEK, Ibaraki T. Uesugi NIRS, Chiba-shi A. Yamazaki LNS, Sendai
	A 150MeV proton FFAG (Fixed Field Alternating Gradient) synchrotron has been constructed to be a prototype for various applications such as proton beam therapy. At the moment, all the components are assembled, and multi-turn injection and beam storage were successfully performed. We are in the phase of beam acceleration up to final energy and expect the beam extraction in a few months. In this paper, beam commissioning results such as multi-turn injection, orbit correction, tune survey and optimization of RF gymnastics will be presented.

THPLT067	Development of Optical Diffraction Radiation Beam Size Diagnostics at KEK Accelerator Test Facility	laser, vacuum, gun, cathode	2643
	V. Karataev, H. Hayano, T. Muto, N. Terunuma, J. Urakawa KEK, Ibaraki R. Hamatsu TMU, Hatioji-shi,Tokyo A. Naumenko, A.P. Potylitsyn Tomsk Polytechnic University, Physical-Technical Department, Tomsk
	Extremely low emittance high current beam is required for the accelerators of the next generation such as linear collider to achieve a reasonable luminosity. However, up to now there is no a simple non-invasive technique for beam diagnostics. A method based on optical diffraction radiation (ODR) appearing when a charged particle passes through a slit between two semi-planes can be one of the promising approaches. The estimations show that it might be possible to measure the beam size as small as 10mcm for a single shot. For a test of the proposed technique we designed an experimental setup and installed it at the extraction line of the KEK-ATF (1.26GeV beam energy, 10¹⁰ e/bunch, rms beam size > 10mcm). The electron beam was moving through a 0.26mm wide slit. We have measured backward ODR angular distribution. We have observed the beam size effect on the measured quantities. The sensitivity to the beam size as small as 20mcm was achieved. However, some undesirable factors such as X-ray background, SR photons coming through the mask slit, big detector angular acceptance have to be reduced. In this case a few micrometers beam size could be measured.

THPLT068	Transverse Bunch-by-bunch Feedback System for the SPring-8 Storage Ring	laser, gun, cathode, cyclotron	2646
	T. Nakamura, S. Daté, T. Ohshima JASRI/SPring-8, Hyogo K. Kobayashi SES, Hyogo-pref.
	A transverse bunch-by-bunch feedback system is developed for the SPring-8 storage ring. An analog de-multiplexer is developed to slice out every six-bunch signal for high-resolution 12-bit ADCs of clock frequency 85MHz, one-sixth of 508MHz RF frequency. Six commercial ADC-FPGA-DAC boards are used for processing the signal from the de-multiplexer. A custom FPGA board is used to multiplex the output signals from those boards. The feedback system is installed in the ring and working with the damping time of 0.5~2.5ms in 30kHz-254MHz and can suppress multi-bunch instabilities driven by impedances of resistive-wall of in-vacuum insertion devices and cavity HOMs at low chromaticity operation.

THPLT069	High Speed Beam Loss Monitor and its Deterioration by Radiation	laser, gun, cathode, cyclotron	2649
	T. Kawakubo, T. Ishida, T. Sanami KEK, Ibaraki
	High speed loss monitor is very useful for tuning and operating the beam in an accelerator, especially in the injection and extraction period. We made a new type loss monitor by connecting a fiber to a photo-multiplier (PMT). In the case that the fiber is made of quartz, the source of the signal is Cherenkov effect. And in the case of scintillation fiber, the signal comes from the scintillation effect. The quartz is much stronger than the scintillator to the radiation, but generating light in the quartz is weaker than scintillator, especially in low energy beam. It is very easy to make this monitor and the fabrication cost is cheap. The monitor can observe the bunch loss with an order of 10 ns. After long time use under high irradiation, the signal of the monitor will decrease. Therefore, we also report the dependence of the signal strength on accumulated radiation in various types of material.

THPLT070	Design and Constriction of Coronagraph for Observation of Beam Halo	laser, gun, cathode, cyclotron	2652
	T. Mitsuhashi KEK, Ibaraki
	The coronagraph is a spatial telescope to observe the sun-corona by artificial eclipse. The concept of this apparatus is to realize the Schlieren-optical system for cutting the bright diffraction fringes in order to observe a less-bright object surrounding the main image such as the sun-corona. We applied this concept for the observation of the surrounding structure (halo, tail) of the beam. Since the background is mainly scattered light come from the objective lens, the key point to observe a less-intense object is to reduce scattering light from objective lens. We used a very well-polished lens (better than scratch and dig 20/20) as objective lens, and succeeded to obtain the signal to background ratio better than 10^-5. As a test, we tried to observe the tail of beam by hiding the central peak with artificial eclipse by the coronagraph at Photon Factory storage ring. We succeeded to observe the tail of beam which has an intensity range of 1/104 of the peak intensity.

THPLT071	Upgraded Symplectic 3D Beam Tracking of the J-PARC 3 GeV RCS	laser, gun, cathode, cyclotron	2655
	M.J. Shirakata, H. Fujimori, Y. Irie KEK, Ibaraki
	The J-PARC 3 GeV ring is a rapid cycling synchrotron which consists of the large bore size magnets. The beam tracking with the 3D distributed magnetic fields is kept developing in order to investigate the beam injection process. In the case of the high intensity hadron accelerator, an accurate beam simulation is important for the designing because a very small amount of beam loss can be critical from the maintenance point of view. In order to improve the tracking accuracy and to save the calculation time, the symplectic integration with the fractal decomposition method has been introduced. The updated simulation results of the beam injection on the J-PARC 3 GeV RCS and the improved performance of ‘GenericSolver' are presented in this paper. The quadrupole fields are also treated as the 3D distributed magnetic fields because they interfered with the bump magnet fields. The remarkable features on the large bore magnet system in the ring accelerator are also discussed.

THPLT072	Magnet and RF Systems of Small Pulse Synchrotron for Radiotherapy	laser, gun, cathode, cyclotron	2658
	K. Endo, K. Egawa, Z. Fang, S. Yamanaka KEK, Ibaraki
	To cure the malignant tumor it is desirable to equalize the treatment level to everybody anywhere he lives in. Proton and/or carbon-ion therapy are now considered as a powerful remedy as the radiation dose can be easily concentrated to the target volume by utilizing the Bragg?s peak. If a small medical accelerator is developed at a reasonable cost, it has a big potential to promote the advanced medical treatment with the accelerator in every place. This pulse synchrotron aims to reduce the size of the accelerator by generating the high magnetic field in a short time which leads to a compact ring of high field magnets. Acceleration time is only 5 msec by using the discharge current of a capacitor bank as large as 200 kA at peak, almost equivalent to half sinusoidal 50 Hz. Part of the discharge current is branched to excite the quadrupole magnets to assure the tracking between the dipole and quadrupole fields. Pulsed power technique is also adopted to drive the RF power tubes. Both magnet and RF systems have been developed and being extensively studied. Technological sides of both systems will be treated in details as well as the computational beam behaviors in this pulse synchrotron.

THPLT073	Numerical Methods for the Orbit Control at the KEK 12 GeV PS	laser, gun, cathode, cyclotron	2661
	Y. Hitaka, H. Sato, M.J. Shirakata KEK, Ibaraki M.K. Kono, Y.M. Yokomichi Miyazaki University, Miyazaki
	At the KEK 12GeV-PS main ring, when the least square method is applied to correct whole beam orbit all at once, it remains unacceptable beam loss and it is necessary to adjust the local positions of the beam orbit by hands with the beam loss monitors until the beam loss is suppressed under an acceptable level. However, the orbit does not realize the minimum-loss condition. In this paper, a new method is proposed. It focuses a fact that the beam loss distribution depends on the shape of the beam orbit and formulates this relationship to a functional approximation by using a nural network algorithm. Then, solving an optimization problem for generated network system, data of the beam shape which is more suitable for the beam loss of the accelerator can be obtained. The description of the system construction and experimental results are presented.

THPLT074	The Beam Loss Monitor System of the J-parc LINAC, 3 GEV RCS and 50 GEV MR	laser, gun, cathode, cyclotron	2664
	S. Lee, T. Toyama KEK, Ibaraki J. Kishiro JAERI/LINAC, Ibaraki-ken M. Tanaka JAERI, Ibaraki-ken
	The high intensity beam accelerator complex itself requires the significant progress of design study and hardware R&D. Operational beam intensity should be limited by the beam loss and activation level of the equipment. Once the beam loss exceeds a criterion at outer environment, beam intensity has to be decreased to prevent the further activation. In order to investigate loss mechanism and suppress the beam loss, a beam loss monitor system have been developed for the J-PARC linac, 3 GeV RCS and 50GeV MR. The system will be essential component for beam commissioning, tuning and machine protection in high intensity beam accelerators. The loss monitor system is composed of scintillator, argon-methane/3He gas filled proportional counter and air filled coaxial cable ionization chamber, which detect g-ray, neutron and charged particles induced by lost particle. It is necessary to measure wide dynamic range of loss intensity for various beam energies. To prevent the activation and heat load by intense beam loss, fast time response of loss signals is required. In this paper, construction and application of loss monitor system are described in detail. Preliminary result of demonstration in the KEK-PS and calibration with cobalt 60 g-ray radiation source are also discussed.

THPLT076	Compact X-band (11.424 Ghz) Linac for Cancer Therapy	laser, gun, cathode, cyclotron	2667
	N.H. Quyet, K. Dobashi, F. Ebina, M. El-Ashmawy, A. Fukasawa, H. Iijima, H. Ogino, M. Uesaka UTNL, Ibaraki
	Since most of medical linacs use S-band frequency, so far, such linacs cannot fit to modern advanced treatment techniques such as Tomotherapy and Stereotactic radiotherapy, which allows physicians to locate the tumor position during treatment time and enable for beam modification based on the real time analysis. Therefore, a new generation of electron linac with the compact size, higher power, higher gradient that can supply the advanced requirements of cancer treatment has been become necessary. X-band frequencies range is one of the suitable frequencies range for design such linacs. In this paper we will describe the possible design of a X-band (11.424 GHz) medical linac with side-coupled standing wave structure which understudying in NERL, The University of Tokyo. We aim to couple the therapy machine to the Compton scattering tunable monochromatic X-ray inspection device to realize the simultaneous inspection/therapy. Detailed design and numerical results are presented.

THPLT077	MPI Parallel Computation of Wake Fields by Using Time Domain Boundary Element Method	laser, gun, simulation, cathode	2670
	K. Fujita, H. Kawaguchi Muroran Institute of Technology, Department of Electrical and Electronic Engineering, Muroran T. Weiland, I. Zagorodnov TEMF, Darmstadt
	This paper presents wake field and wake potential calculation by using the Time Domain Boundary Element Method (TDBEM) on the MPI parallel computation system. The TDBEM is based on the electric field integral equation (EFIE) and the electric field integral equation (MFIE) in time domain. In wake field simulation, an important advantage of these equations is that electromagnetic fields in an accelerator cavity are explicitly expressed as a sum of charged particle self-fields and wake fields in time domain. On the other hand, the TDBEM has serious difficulties in practical numerical simulation, such as numerical instabilities, huge memory requirements, and heavy calculation cost. However, recent remarkable progress of computer performance makes the TDBEM possible to be used in practical simulations. According to these backgrounds, we apply the TDBEM to wake field simulation in the MPI parallel computer system. Simulation results are compared with that of a conventional method, the Finite Integration Techniques (FIT), and good agreements are shown.

THPLT078	Construction of FFAG Accelerators in KURRI for ADS Study	laser, gun, simulation, booster	2673
	M. Tanigaki, K. Mishima, S. Shiroya KURRI, Osaka S. Fukumoto, Y. Ishi Mitsubishi Electric Corp, Energy & Public Infrastructure Systems Center, Kobe M. Inoue SLLS, Shiga S. Machida, Y. Mori KEK, Ibaraki
	KART (Kumatori Accelerator driven Reactor Test) project has started at Kyoto University Research Reactor Institute (KURRI) from the fiscal year of 2002. The purpose of this project is to demonstrate the basic feasibility of ADS, studying the effect of incident neutron energy on the effective multiplication factor of the subcritical nuclear fuel system. We are now constructing a proton FFAG accelerator complex as a neutron production driver for this project. Our accelerator complex consists of a 2.5 MeV FFAG betatron as an injector and 20 MeV and 150 MeV FFAG synchrotrons as a booster and a main ring, respectively. Our FFAG betatron is a spiral sector type. Both booster and main rings are radial sector type FFAG synchrotrons, but different in the production of required magnetic field with a certain magnetic field index. The distribution of magnetic field is determined by the shaped pole-face in the main ring while the magnetic field is realized by use of trim coils in the booster ring. This FFAG complex will be combined with our Kyoto University Critical Assembly (KUCA) in KURRI by the end of March 2006 and the experiments will begin as soon as the whole system is ready.

THPLT079	The Study of APF-IH Linac	laser, gun, booster, cathode	2676
	K. Yamamoto, T. Hattori, K. Yamamoto RLNR, Tokyo M. Okamura RIKEN, Saitama S. Yamada NIRS, Chiba-shi
	We have manufactured the IH linac with Alternating Phase Focus as the test machine of medical accelerator injection. It will accelerate C⁴⁺ ion up to 2MeV/u from 40 keV/u, the tank length is around 1.5m, operation frequency is 100MHz. Furthermore, We have succeeded the acceleration test using proton with simple acceleration system consist of P.I.G. ion source, bending magnets and focus lenses, less than 5m long. Otherwise, We have been making the program of beam dynamics with the results of the electro-magnetic simulation soft (Micro-Wave-Studio,OPERA-3D), it has the merit of easily to calculate the 3D- beam dynamics in the tank. We will report the some results of the test and the beam simulation and the comparisons.

THPLT080	Simulation Study of the Beam Loading Effect in an RF Gun	laser, gun, booster, cathode	2679
	K. Shinto, H. Hama, F. Hinode, A. Miyamoto, T. Tanaka LNS, Sendai
	Because of simple structure and apparatus, a thermionic rf gun has been considered to be employed in a new pre-injector for the future synchrotron radiation facility at Tohoku University. A 3-D beam simulation code for the rf gun using a Finite Difference Time Domain (FDTD) method to solve Maxwell's equations has been developed. In the rf gun, especially in case of the high beam current, electromagnetic fields induced by the electron beam are considered to affect beam characteristics such as beam emittance and energy spread. In the FDTD method, because the Maxwell?s equations are able to be solved including the term of current density of the charge, the electromagnetic fields produced by both the external rf power and the electron beam can be anticipated. Using the simulation code, beam loading effects on the characteristics of the electron beam extracted from the rf gun is investigated.

THPLT081	Present Status of Photo-cathode RF Gun System and its Applications at Waseda University	electron, booster, laser, cyclotron	2682
	R. Kuroda, Y. Hama, K. Hidume, H. Hirama, M. Kawaguchi, N. Kudo, T. Kuribayasi, S. Minamiguchi, R. Moriyama, T. Saito, K. Sakaue, D. Ueyama, M. Washio RISE, Tokyo H. Hayano, J. Urakawa KEK, Ibaraki S. Kashiwagi ISIR, Osaka X.J. Wang BNL/NSLS, Upton, Long Island, New York
	High quality electron beam generation using photo-cathode rf gun system and its application have been developed at Waseda University. This system can generate about 4 MeV low emittance electron beam. This is applied for soft X-ray generation using laser Compton scattering and pulse radiolysis experiments based on the pump-probe technique. In case of the soft X-ray generation, Compton scattering experiments between about 4.2 MeV electron beam and Nd:YLF laser light (1047nm) is performed at 20 degrees interaction angle, so that about 300 eV soft X-ray is generated. In case of the pulse radiolysis experiments, the electron beam is used for the pump beam. The probe light is generated as white light by concentrating Nd:YLF laser light (1047nm) on the water cell. The measurement with about 30 ps (FWHM) time resolution of this system is demonstrated for the absorption of hydrated electrons. In this conference, we will present the experimental results, status of this system and future applications.

THPLT082	Beam Diagnostics for a Photocathode Rf-gun System	emittance, booster, electron, cyclotron	2685
	K. Sakaue, N. Kudo, R. Kuroda, M. Washio RISE, Tokyo H. Hayano, J. Urakawa KEK, Ibaraki S. Kashiwagi ISIR, Osaka
	Beam diagnostic systems for high quality electron beam emitted from photo-cathode rf gun have been developed. Beam characteristics such as bunch length and emittance measurements were performed at Waseda University. The bunch length was measured using an rms bunch length monitor based on beam spectrum analysis. The monitor is very useful as the non-destructive and conventional tool even for the relatively low energy electron beam around 5MeV. The measurement results of the rms bunch lengths using this monitor are in good agreement with the simulation results of PARMELA. However, it is not applicable for the measurement of longitudinal profile of the electron bunch, so that we have started the manufacturing of a deflection cavity, so-called RF-Kicker, to measure the longitudinal profiles of the bunch. The emittance has been measured by using a slit scan technique. By using double slit scan technique, emittance of 9mmmrad has been obtained. Though the value is not satisfactory small, we believe that much smaller emittance can be obtained by optimizing a laser profile. The measurement results and progress of rf gun at Waseda University will be presented at the conference.

THPLT083	Femto-second Bunch Length Measurement using the RF Deflector	emittance, booster, cyclotron, focusing	2688
	S. Kashiwagi, G. Isoyama, R. Kato, K.K. Kobayashi, Y. Matsui, A. Saeki, J. Yang ISIR, Osaka H. Hayano, M. Kuriki KEK, Ibaraki M. Kudo, M. Washio RISE, Tokyo
	The traveling wave type rf cavities operating in dipole mode (TM110-like) is being developed for a measurement of femto-second electron bunch. The femto-second electron bunch is used the pulse radiolysis experiments for the studies on radiation physics and chemistry with femto-second time resolution. The resonant frequency is tuned to the designing value 2856 MHz, which is accelerating frequency of a photo-injector linac at ISIR Osaka University. Further, we are planning to apply the design of the traveling wave rf deflector to a X-band crab cavities for the Global Linear Collider (GLC) project. In this conference, we will report the design of the traveling wave rf deflector and the result of cold test.

THPLT084	Test Result of Slow Global Orbit Feedback using MATLAB at PLS	feedback, emittance, booster, cyclotron	2691
	H.-S. Kang, J. Choi, K.M. Ha, E.-H. Lee, T.-Y. Lee, W.W. Lee PAL, Pohang
	A slow global orbit feedback using MATLAB has been tested to control the slow orbit movement for the PLS. The feedback program uses MATLAB tools such as matrix algebra, mathematical functions, and graphic display, and uses the SVD (singular value decomposition) method. The PLS uses 70 corrector magnets with the maximum angle of 2-mrad for each plane among which 11 use the 16-bit DAC power supplies for the insertion device orbit control and others the 12-bit corrector power supplies with the minimum step of 1-micro-rad, and thus the orbit feedback is not acceptable to beamline users. For the best performance of the feedback, the major hardware components have been upgraded: the replacement of 12-bit BPMs with 16-bit was completed, and the upgrade of corrector power supplies from DAC 12-bit to 18-bit or higher will be completed soon. In this paper, the orbit feedback test result using the current corrector power supplies is presented and the upgrade plan of orbit feedback is described.

THPLT085	Reengineering and Refactoring Large-scale Scientific Programs with the Unified Process: A Case Study with OSIRIS PIC Program	feedback, emittance, booster, cyclotron	2694
	J.B. Kim, I.S. Ko POSTECH, Pohang, Kyungbuk H. Suk KERI, Changwon
	As science and engineering problems get more complex, programs which help modelling complicated problems larger and more sophisticated. This trend makes us recognize the importance of well-established engineering disciplines not only in designing large-scale scientific programs for special purposes in appropriate development time but also in importing the programs from other research group and refactor it for conveniences and more advanced applications. OSIRIS is a large-scale PIC code which was developed at UCLA for modelling of laser-plasma interactions. OSIRIS was reengineered and documented in UML by our group and ported to Linux cluster machine of 8 nodes. We report our current status of developing the extended version of OSIRIS, which was named as OSIRIS-X, and how a large-scale scientific programs can be enhanced efficiently with the Unified Process. Some guidelines in designing and refactoring large-scale scientific codes are presented and discussed. A common architecture model of numerically intensive programs for large-scale computing is suggested , and it is discussed how we can use it for rapid development and prototyping of scientific programs. We also discuss future challenges and prospects in OSIRIS-X development.

THPLT086	High Temporal Resolution, Single-shot Electron Bunch-length Measurements	feedback, electron, emittance, booster	2697
	G. Berden, B. Redlich, A.F.G. Van der Meer FOM Rijnhuizen, Nieuwegein W.A. Gillespie, A. MacLeod UAD, Dundee S.P. Jamison Strathclyde University, Glasgow
	A new technique, combining the electro-optic detection of the Coulomb field of an electron bunch and the single-shot cross-correlation of optical pulses, is used to provide single-shot measurements of the shape and length of sub-picosecond electron bunches. As in our previous technique [I. Wilke et al., Phys. Rev. Lett. 88, 124801 (2002)], the electric field of the electron beam is encoded electro-optically on an optical pulse. Our earlier measurements, which involved encoding the time profile of the electron bunch on the spectrum of the optical pulse, showed electric field profiles with a FWHM of the order of 1.7 ps. The new method offers a much better time resolution since it avoids the significant measurement artifacts that can arise in our previous (spectral encoding technique due to the coupling between the temporal envelope and spectral content of the optical pulse. The cross-correlation technique has been applied to the measurement of electron bunches in FELIX, showing single bunches of around 500fs FWHM. The resolution is limited primarily by the electro-optic crystal thickness and the relatively low energy of the electrons (50 MeV).

THPLT089	MATLAB Based TPSA Toolbox for the Particle Mapping Through Three-dimensional Magnetic Fields	feedback, electron, emittance, booster	2700
	H.-P. Chang, H.-J. Tsai NSRRC, Hsinchu
	Based on the object-oriented programming of MATLAB, a truncated power series algebra (TPSA) toolbox has been developed. The TPSA toolbox as a differential algebra has been applied to realize the algorithm of particle mapping through three-dimensional magnetic field configurations. The capability of symbolic calculation by using this MATLAB-based TPSA toolbox can be used for the theoretical simulation and modeling in accelerator physics. Associated with the use of MATLAB in the control of machines, one can derive the real machine with a virtual machine model built in MATLAB. In this paper, the method of symplectic mapping of three-dimensional magnetic fields is introduced and the structure of TPSA toolbox is presented. Applications of TPSA toolbox in the symplectic mapping of three-dimensional magnetic fields are demonstrated as well.

THPLT090	The Operating of Digital Beam Position Monitor in NSRRC	feedback, electron, emittance, booster	2703
	C.H. Kuo, J. Chen, K.-T. Hsu, K.H. Hu, D. Lee NSRRC, Hsinchu
	The digital beam position monitors are configured to operation system in the NSRRC now. This integration includes of multi-channel access, channel calibration, gain control, and parameter control to meet various operation condition, perform functionality and performance evaluation. The programmability nature of DBPM system is essential for multi-mode high precision beam position measurement. The system will support high performance beam position, turn-by-turn beam position, tune and other diagnostic measurements. Control system interface was implemented to support the operation of DBPM system. T various aspects will be discussed and presented in this report.

THPLT091	The Synchrotron Radiation Monitor Upgradation in NSRRC	feedback, electron, emittance, cyclotron	2706
	C.H. Kuo, J. Chen, K.-T. Hsu, S.Y. Hsu, Y.-T. Yang NSRRC, Hsinchu
	Synchrotron radiation monitor in the storage has been operated for a long time. This system is upgrading to booster operation now. The basic system includes optics, digital image acquisition, image analysis, compressed image transportation and visualization tools at workstation. The linearity and dynamic of new is discussed for some beam physics study. This system is also supported to the booster by new camera and addition operation. The hardware configuration and software structure will be summarized in this report.

THPLT093	Particle-in-cell Numerical Simulations of Particle Dynamics in Beams and ECR Sources	feedback, plasma, emittance, ion	2709
	G. Shirkov, V. Alexandrov, V. Shevtsov JINR/PPL, Dubna, Moscow Region
	A summary of recent development of physical and mathematical basements and the first version of computer code library based on the particle-in-cell method are presented. The code library is aimed for the three-dimensional (3D) simulation of the ECR plasma and ion production in the ECR ion source. The particle-in-cell (finite particle) method is one of the most powerful methods for the numerical simulation of multicomponent ECR plasma and electron-ion beams. This method allows studying the detailed characteristics of plasma, taking into account the distribution functions of particles (spatial, velocity and energy distributions), real self and external fields, particle-particle interactions and many other effects. This technique promises to provide very precise numerical simulations and optimizations of ECR ion sources. The first results of simulations of ECR source plasma are presented. It has been shown that a complete and adequate description of ECR plasma requires the full-scale 3D model and computer codes. This is out of frames of existed project and could be an aim of some addition investigations.

THPLT094	Ordered Ion Beam in Storage Rings	feedback, plasma, ion, emittance	2712
	A. Smirnov, I.N. Meshkov, A.O. Sidorin, E. Syresin, G.V. Troubnikov JINR, Dubna, Moscow Region T. Katayama CNS, Saitama H. Tsutsui SHI, Tokyo
	The using of crystalline ion beams can increase of the luminosity in the collider and in experiments with targets for investigation of rare radioactive isotopes. The ordered state of circulating ion beams was observed experimentally at several storage rings. In this report a new criteria of the beam orderliness are derived and verified with BETACOOL code with using molecular dynamics technique. The sudden reduction of momentum spread observed on a few rings is described with this code. The simulation shows a good agreement with the experimental results. The code has then been used to calculate characteristics of the ordered state of ion beams for ion rings which will have experimental programs for the study of crystalline beams. A new strategy of the cooling process is proposed which permits to increase the linear density of the ordered ion beam.

THPLT095	Nuclotron Extracted Beam Spill Control	plasma, ion, emittance, feedback	2715
	V. Volkov, V. Andreev, E. Frolov, V. Karpinsky, A. Kirichenko, A.D. Kovalenko, V.A. Mikhaylov, S. Romanov, B. Vasilishin, A. Volnov JINR, Dubna, Moscow Region
	The first experiments with the Nuclotron Beam Slow Extraction System (BES) were carried out in December 1999. After the BES commissioning, the development of the system was continued together with experiments on relativistic nuclear physics. To realize the constant-current-beam or the constant-time-length spill and to suppress the low frequency spill structure in the range up to several hundred hertz, a spill control subsystem was designed and put into operation. It consists of a feedback loop in parallel with a feed-forward control. In the feedback loop the extracted particle flux is measured with beam current monitor and is compared with the request flux. The resulting error signal is fed into a feedback controller. The controller is an analog unit in which integration, differentiation and gain can be adjusted separately. The output control signal is added to the extraction quadrupoles power supply pattern generated by the corresponding function generator. The beam spill control subsystem has been improved in stages since its commissioning in 2000. The beam spill duration of more than 10s and the beam spill uniformity of about 0.9 were achieved in recent Nuclotron runs.

THPLT099	The Analysis of the Electron Beam Scanning Method for the Beam Profile Monitoring.	plasma, emittance, feedback, cyclotron	2718
	D.A. Liakin ITEP, Moscow
	The method of the beam profile monitoring with scanning electron beam is analyzed. Simulation model of the ion/electron beam interaction is presented and some simulation results are shown. In the report the estimation of overall performance characteristics of this method such as sensitivity, spatial resolution, frequency bandwidth etc. are given.

THPLT100	Development of a Permanent Magnet Residual Gas Profile Monitor With Fast Readout	plasma, emittance, feedback, cyclotron	2721
	D.A. Liakin, S.V. Barabin, V. Skachkov ITEP, Moscow P. Forck, T. Giacomini GSI, Darmstadt A. Vetrov MSU, Moscow
	The beam profile measurement at modern ion synchrotrons and storage rings require high timing performances on a turn-by-turn basis. From the other hand, high spatial resolutions are very desirable for cold beams. We are developing a residual gas monitor to cover the wide range of beam currents and transversal distributions of particles. It supplies the needed high-resolution and high-speed tools for beam profiling. The new residual gas monitor, will operate on secondary electrons whose trajectories are localized within 0.1 mm filaments. The required magnetic field of 100 mT will be excited by a permanent magnet. In the fast turn-by-turn mode the beam profile will be read out with a resolution of 1 mm by a 100-channel photodiode-amplifier-digitizer. The high resolution mode of 0.1 mm is provided by a CCD camera with upstream MCP-phosphor screen assembly. In this paper the first results of the photodiode-digitizer device testing, the compact mechanical design features and simulation results of the permanent magnet device are presented.

THPLT102	Characteristics of Sealed-off Electron Gun with Wide Beam	plasma, gun, emittance, feedback	2724
	V.M. Pirozhenko MRTI RAS, Moscow A.N. Korolev, K.G. Simonov ISTOK, Moscow Region
	Compact sealed-off electron gun is a new promising type of devices. The gun generates wide beam of electrons with energy up to 200 keV and high peak power in 2-microsecond pulses. The beam is extracted to the atmosphere or a gas through the foil being uniformly distributed over the area of exposure. The gun contains the long ribbon cathode of oxide type, the electrodes for forming required distribution of the beam, the output window with 20-micron titanium foil, the high-voltage ceramic insulator, and the vacuum casing of rectangular shape. The gun is applied in the radiation technology system intended for the treatment of continuously moving tapes with 300 mm width. The gun design provides 10% uniformity of the radiation dose on the tape width.

THPLT106	Measurement of Beam Polarization in VEPP-3 Storage Ring using Internal Target-based Moeller Polarimeter	plasma, gun, polarization, emittance	2727
	A.V. Grigoriev, V. Kiselev, E.V. Kremyanskaya, E. Levichev, S.I. Mishnev, S.A. Nikitin, D.M. Nikolenko, I.A. Rachek, Y.V. Shestakov, D.K. Toporkov, V.N. Zhilich BINP SB RAS, Novosibirsk
	A method for beam polarization measurement in a storage ring has been for the first time developed and applied based on measuring the asymmetry in scattering of polarized beam electrons on the internal polarized gas jet target. Using this method we have studied the polarization in VEPP-3 booster storage ring. VEPP-3 is the source of polarized beams for VEPP-4M electron-positron collider in the planned experiment on high-precision mass measurement of tau-lepton near the production threshold of the latter (1777 MeV). Radiative polarization of beams obtained in VEPP-3 is used for absolute calibration of particle energy by the resonant depolarization technique after injection into VEPP-4M ring. The polarimeter design is described. Results of polarization measurements performed in 60 MeV range of VEPP-3 energy contiguous from above to tau-lepton production threshold are presented and discussed. The depolarizing influence of the integer machine spin resonance (1763 MeV) as well as of the combination spin resonances with the betatron frequencies are found to be significant.

THPLT107	VEPP-4M Optical Beam Profile Monitor with a One-turn Temporal Resolution	plasma, gun, polarization, emittance	2730
	O.I. Meshkov, V.F. Gurko, A.D. Khilchenko, V. Kiselev, N.Y. Muchnoi, N.A. Selivanov, V.V. Smaluk, A.N. Zhuravlev, P.V. Zubarev BINP SB RAS, Novosibirsk
	The transverse beam profile monitor based on Hamamatsu multi-anode photomultiplier with 16 anode strips is used at the VEPP-4M collider. The monitor is applied to study turn-to-turn dynamics of the transverse beam profile during 131 000 turns. The device provides a permanent measurement of synchrotron and betatron frequencies as well.

THPLT108	The Study of the Beam TAILS with the Optical Coronagraph	plasma, gun, polarization, emittance	2733
	O.I. Meshkov, M.G. Fedotov, E.V. Kremyanskaya, E. Levichev, N.Y. Muchnoi, Yu.A. Pakhotin, N.A. Selivanov, A.N. Zhuravlev BINP SB RAS, Novosibirsk
	Optical white-light Lyot coronograph is applied at the VEPP-4M collider to study the "tails" of the transverse beam profile. The device is used for investigation of the beam-beam effects.

THPLT109	The Upgraded Optical Diagnostic of the VEPP-4M Collider	plasma, gun, polarization, emittance	2736
	O.I. Meshkov, M.G. Fedotov, V.F. Gurko, A.D. Khilchenko, N.Y. Muchnoi, Yu.A. Pakhotin, N.A. Selivanov, A.N. Zhuravlev, E.I. Zinin, P.V. Zubarev BINP SB RAS, Novosibirsk
	The upgraded optical diagnostic of the VEPP-4M collider is described. The system abilities are improved sufficiently in comparing with the previous version. Now the diagnostic supplies the data about an electron/positron beam transversal and longitudinal size, shape and position. It is applied to study the electron beam "tails" and turn-to-turn beam profile dynamics. The system is used to tune of the beam pass-by from the VEPP-3 booster to the VEPP-4M collider and provides the permanent measurements of the synchrotron and betatron frequencies.

THPLT110	Modelling of Accelerating Structures with Finite-difference Time-domain Method	plasma, gun, polarization, emittance	2739
	E.V. Pickulin, V.N. Malyshev LETI, Saint-Petersburg S.A. Silaev, Y.A. Svistunov NIIEFA, St. Petersburg
	A finite-difference time-domain (FDTD) method is very popular for electromagnetic field modeling. The practical interest in the method is the ability to calculate fields in time domain at any time point in the accelerating structure. That is to say the FDTD method is able to model transient process taking into account the peculiarity of RF power input device. A FDTD approach for modeling of alternate phase focusing structure is presented in this paper. The modeling of lossy metals is a problem in classical formulation of FDTD method. This matter is investigated and one of the solutions is presented in this paper. There are some problems of signal processing when using time-domain method for resonant structure modeling. The matters of mode determination are also investigated and presented in this paper. The simulation results are compared with experimental data.

THPLT111	An Accelerator-based Thermal Neutron Source for BNCT Application	plasma, gun, polarization, emittance	2742
	A. Makhankov, A. Gervash, R. Giniyatulin, I. Mazul, M. Rumyantsev NIIEFA, St. Petersburg J. Esposito, L.B. Tecchio INFN/LNL, Legnaro, Padova V. Khripunov RRC Kurchatov Institute, Moscow
	An accelerator-based thermal neutron source, aimed at the BNCT treatment of skin melanoma is in construction at the INFN-LNL in the framework of SPES project. The BNCT device exploit the intense proton beam provided by a 5 MeV, 30 mA RFQ that represent the first accelerating step of the SPES exotic nuclei production beam facility. Neutrons are generated by 9Be(p,n)9B nuclear reaction in a high power (150 kW) Beryllium target. The operational condition of the Beryllium converter is close to the condition of Be-armoured components in fusion reactors. The main difference consists in the necessity of limitation of structural materials amount used in the design in order to meet therapeutic irradiation requirements. Two possible design of neutron converter are developed: one with saddle block tiles brazed to CuCrZr tubes and another one with Be target made from solid Be block. Results of R&D works on the development of water cooled Be target for converter are presented, including data on selected materials, technological trials and mockups high heat flux testing.

THPLT112	Methods and Instrumentation for Measurement of Low Ion Beam Currents at Cryring	plasma, gun, polarization, emittance	2745
	A. Paal, A. Källberg, A. Simonsson MSL, Stockholm J. Dietrich, I. Mohos FZJ/IKP, Jülich
	In many CRYRING experiments an accurate measurement of the circulating ion beam current is essential for determination of e.g. absolute cross sections. However, the current produced from the ion source can be very low. Furthermore, when surface barrier detectors are used, for example in the merged electron-ion beam experiments, the current has to be kept low to avoid saturation. With new electronics, using an Integrating Current Transformer with 5 V/A sensitivity, the current resolution of the Bergoz Beam Charge Monitor (BCM) has been increased to below 1 nA for bunched beams. The sum signal of the capacitive pick-up located at the farthest point from the RF-system is integrated by a second gated integrator. The RMS resolution is about 100 pA. To measure the intensity of coasting beams neutral particle detectors and a residual-gas beam profile monitor are used, calibrated with the BCM output during 20-100 ms after acceleration. The micro-channel plate detectors can handle a few Mcps count rate with a maximum 1 cps dark count rate. Presently a 50 Mcps secondary electron multiplier is being tested as a neutral particle monitor, having a maximum dark count rate of 0.05 cps

THPLT113	Conceptual Design of a Microwave Confocal Resonator Pick-up	plasma, gun, polarization, emittance	2747
	V.G. Ziemann, A. Ferrari, T. Lofnes TSL, Uppsala F. Caspers, I. Syratchev CERN, Geneva
	A confocal resonator may be used as a pick-up for frequencies in the multi-GHz region. In this report we discuss the design by analytical and numerical methods of such a device. Furthermore we discuss engineering issues such as the damping of unwanted modes, shielding of image fields and manufacturing tolerances. Such a device can be used both as pick-up and kicker where the actual structure is several wavelengths away from the beam in the transverse direction. It is intended for highly relativistic beams and does not require changing particle trajectory as opposed to a diagnostic wiggler.

THPLT114	A New Mono-energetic Neutron Beam Facility in the 20-180 MeV Range	plasma, gun, polarization, emittance	2750
	V.G. Ziemann, L.-O. Andersson, T. Bergmark, O. Bystrom, A. Bäcklund, H. Calen, L. Einarsson, C. Ekström, J. Fransson, K.J. Gajewski, N. Haag, T. Hartman, E. Hellbeck, T. Johansen, O. Jonsson, B. Lundström, R.P. Peterson, L. Pettersson, A. Prokofiev, D. Reistad, P.-U. Renberg, R. Wedberg, D. Wessman, L. Westerberg, D. van Rooyen TSL, Uppsala J. Blomgren, S. Pomp, U. Tippawan, M. Österlund INF, Uppsala
	Recent interest in nuclear applications involving neutrons, like ransmutation of nuclear waste, fast-neutron cancer therapy, dose to personnel in aviation and electronics failures due to cosmic-ray neutrons, motivate the development of a facility producing intense mono-energetic neutron beams. At The Svedberg laboratory (TSL), Uppsala, Sweden, we have developed such a facility by utilizing the existing cyclotron and inserting a flexible Lithium target in a rebuilt beam line. The new facility can operate at unsurpassed quasi-monoenergetic neutron intensities and provides large flexibility of the neutron beam properties, like diameter and shape.

THPLT122	The Energy Deposition Profile of 0.1-3.0 MeV Electrons in NaCl	plasma, gun, polarization, emittance	2753
	V.V. Gann NSC/KIPT, Kharkov A.V. Sugonyako, D.I. Vainshtein, H.W. den Hartog RUG, Groningen
	An analysis is presented of existing experimental and theoretical data of energy loss profiles and energy deposition in thick targets irradiated with MeV-energy electrons. A simple approximate calculation is proposed for the energy deposition profile of a perpendicular beam of 0.1-3 MeV electrons in matter. The results obtained with this method are in agreement with existing calculated and measured energy absorption profiles for a variety of materials. It will be shown that the build-up phenomenon has a significant effect on the energy deposition profile in thick samples. A systematic experimental investigation of the energy deposition profile of 0.5 MeV electrons in 0.2 - 0.8 mm thick NaCl platelets has been carried out. The distribution of the absorbed dose was determined with differential scanning calorimetry method by measuring either the latent heat of melting of the radiation-induced Na-precipitates or the stored energy.

THPLT123	Coupling Coefficients in the Inhomogeneous Cavity Chain	plasma, gun, polarization, emittance	2756
	K. Kramarenko, M.I. Ayzatskiy NSC/KIPT, Kharkov
	In this paper a mathematical method on the base of a rigorous electrodynamic approach for description of inhomogeneous chain of cylindrical cavities is presented. The form of the obtained for chosen amplitudes set of equations is similar to the set of equations that describe the simple coupled circuit chain. As the cavity have the infinite number of resonant frequencies, to obtain the coupling coefficients one have to solve additional infinite set of linear equations with coefficients that depend on the frequency. Using the developed method in the case of inhomogeneous cavity chain we calculated the dependence of the coupling coefficients on frequency and geometrical sizes with taking into account the 'long-range' coupling.

THPLT124	Simulation Technique for Study of Transient Self-consistent Beam Dynamics in RF Linacs	plasma, gun, polarization, emittance	2759
	V.V. Mytrochenko, A. Opanasenko NSC/KIPT, Kharkov
	The report describes a simulation technique for study of unsteady self-consistent dynamics of charged particles in resonant linacs. The technique allows simulating the linacs that consist of resonant cavities and traveling wave sections. The proposed approach is based on unsteady theories of excitation of resonant cavities and waveguides by a beam of charged particles and RF feeders. The theory of waveguide excitation is generalized to the case of spatially inhomogeneous traveling wave structures. The system of self-consistent differential equations for fields and motion of particles is integrated over time and space. The SUPERFISH code is used to evaluate characteristics of the axially symmetrical cavities and traveling wave sections. The PARMELA code is applied to simulate motion of the particles at each time step of the integration. In such a way the fields and beam characteristics in the axially symmetrical accelerating structures can be obtained for transient and steady state operation. Description of the algorithm and results of its validation are presented.

THPLT127	Beam Diagnostics Systems for the Diamond Synchrotron Light Source	plasma, gun, polarization, electron	2762
	G. Rehm, A.F.D. Morgan, C. Thomas Diamond, Oxfordshire
	We present an overview of the diagnostics systems that will be implemented at the Diamond synchrotron light source. The aim of this paper is to give a complete picture of the systems to measure the quality of the electron beam from the injector through to the storage ring. We will show how we intend to measure the dimensions, the position and the time structure of the electron bunches. In addition, the instrumentation to measure the charge, the current and the emittance of the electron beam will be described. Finally, systems to provide accurate measurement of electron losses and the injection efficiency will be detailed.

THPLT129	Ion Chambers for Monitoring the NuMI Beam at FNAL	plasma, gun, proton, polarization	2765
	S.E. Kopp, D. Indurthy, R. Keisler, S. Mendoza, Z. Pavlovich, M. Proga, R.M. Zwaska The University of Texas at Austin, Austin, Texas M. Diwan, B. Viren BNL, Upton, Long Island, New York A.R. Erwin, H.P. Ping, C.V. Velisaris UW-Madison/PD, Madison D. Harris, A. Marchionni, J. Morfin Fermilab, Batavia, Illinois J. McDonald, D. Naples, D. Northacker University of Pittsburgh, Pittsburgh, Pennsylvania
	We summarize selected instrumentation under construction for the NuMI neutrino beam facility at Fermilab. An array of foil secondary emission monitors (SEM's) will measure the 120GeV proton beam position, profile and halo at 10 stations along the transport to the NuMI target. The final two foil SEM's align the proton beam to within 50 microns on target. These are capable of withstanding the 400kW proton beam and causing <5·10^-6 beam loss. Further instrumentation includes four stations of ionization chambers located downstream of the decay volume, one upstream and three downstream of the beam dump. The latter three monitor the tertiary muon beam, the first monitors the remnant hadron beam. The ion chamber arrays align the proton beam to 14microRadian and the neutrino beam to within 50 microRadian, as well as monitoring flux to better than 1%. The ion chambers are designed to withstand the ~1GRad doses and 10⁹ particle/cm²/spill fluxes anticipated during NuMI beam operations. Beam tests and R&D efforts are discussed.