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

injection

Paper	Title	Other Keywords	Page
MOPKF033	Operational Improvements in the ESRF Injection Complex	undulator, booster, wiggler, radiation	375
	Y. Papaphilippou, P. Elleaume, L. Farvacque, L. Hardy, G.A. Naylor, E. Plouviez, J.-L. Revol, B.K. Scheidt, V. Serriere ESRF, Grenoble
	The ESRF injection complex, comprising a 200MeV linac, a booster accelerator with a top energy of 6GeV and two transfer lines, has been routinely injecting beam to the storage ring since the beginning of its operation. The newly implemented injection with ‘‘front-end open'' triggered several operational improvements in order to maximise the reliability of the complex. A series of diagnostics (sychnotron light monitors, striplines, fast current transformers) were implemented allowing the measurement and monitoring of several components of the injected beam. New optics models were constructed and several application systems as the closed orbit correction or tune measurements have been upgraded. The operational procedures of injection at 100MeV in the booster and the injection efficiency maximisation were renewed and improved. Further developments for the uninterrupted operation of the storage ring during injection, such as the bunch cleaning in the booster were successfully tested.

MOPKF034	Status of the Development of Superconducting Undulators at the ESRF	undulator, booster, wiggler, radiation	378
	E.J. Wallén, J. Chavanne, P. Elleaume ESRF, Grenoble
	This note describes the present status of the development of superconducting undulators at the ESRF. Magnetic models of superconducting undulators suitable for the ESRF storage ring have been developed and evaluated. The superconducting undulators studied are horizontally polarizing undulators with a flat field profile and the vertical physical aperture of the undulator is 6 mm. Both 2D models of the local field in a period of the undulator and 3D models of the complete superconducting undulator, including the end sections and current leads, have been evaluated. The practical limit for the obtainable magnetic field has been estimated from the known performance of superconducting wire available from the cabling industry. This note also describes the conceptual design of the cryostat of the superconducting undulator and estimations of the expected heat load to the cryostat at different filling modes of the storage ring.

MOPKF035	Stabilization of the Pulsed Regimes on Storage Ring Free Electron Laser: The Cases of Super-ACO and Elettra	booster, wiggler, electron, damping	381
	C. Bruni, D. Garzella, G. Lambert, G.L. Orlandi LURE, Orsay E. Allaria, R. Meucci INOA, Firenze S. Bielawski PhLAM/CERCLA, Villeneuve d'Ascq Cedex M.-E. Couprie CEA/DSM, Gif-sur-Yvette M. Danailov, G. De Ninno, B. Diviacco, M. Trovò ELETTRA, Basovizza, Trieste D. Fanelli KTH/NADA, Stockholm L. Giannessi ENEA C.R. Frascati, Frascati (Roma)
	In a Storage Ring Free Electron Laser (SRFEL) a relativistic electron beam interacts with the magnetostatic periodic field of an undulator, thus emitting synchrotron radiation. The light is stored in an optical cavity and amplified during successive turns of the particles in the ring. The laser intensity may appear as a "continuous wave (cw)" or show a stable pulsed behaviour depending on the value of the temporal detuning, i.e. the difference between the electron beam revolution period and the round trip of the photons in the cavity. It was recently shown, that the loss of stability in a SRFEL occurs through an Hopf bifurcation []. This observation opens up the perspective of introducing a derivative self-controlled feedback to suppress locally the bifurcation and enlarge the region of stable signal. A feedback of this type has been implemented on Super-ACO and shown to produce a significant and reproducible extension of the stable "cw" region. We review here these results and discuss new experiments performed on the Super-ACO and ELETTRA SRFELs. G. De Ninno and D. Fanelli, Phys. Rev. Lett. in press; M.E. Couprie et al. Nucl. Instrum.and Meth. A., in press

MOPKF036	Wideband Infrared FEL	undulator, booster, wiggler, vacuum	384
	J.-M. Ortega, F. Glotin, R. Prazeres LURE, Orsay
	The infrared free-electron laser offers the advantage of a potential large tunability since the FEL gain itself remains subtantially high throughout the infrared spectral range, provided that the electron beam quality remains sufficient at low energy. Moreover, the reflectivity of metal mirrors used in the optical cavity remains close to unity from the near infrared up to the microwave range. The main limitation comes from the diffraction of the optical beam due to the finite size of the vacuum chamber of the undulator and other optical cavity elements. The undulator magnetic gap, and thus magnetic chamber inner heigth, cannot be made arbitrarily large since one needs a K parameter sufficiently large to produce a large wavength tunability (typically K > 2). The diffraction losses can however be further reduced by using an elliptical vacuum chamber inside the undulator and elliptical, instead of spherical, mirrors. Then the optical beam is partially guided inside the chamber. Working in this regime at CLIO, we have obtained an FEL tunable from 3 to 120 μm by operating the accelerator between 50 and 14 MeV. This is the largest spectral range ever obtained with a single optical cavity. We plan to use larger mirrors to further reduce the diffraction produced at the edges of the undulator chambers in order to increase the maximum wavelength to approximately 200 μm

MOPKF037	FERMI@ELETTRA: 100 nm - 10 nm Single Pass FEL User Facility	booster, wiggler, linac, vacuum	387
	R.J. Bakker, C. Bocchetta, P. Craievich, G. D'Auria, M. Danailov, G. De Ninno, S. Di Mitri, B. Diviacco, G. Pangon, L. Rumiz, L. Tosi, V. Verzilov, D. Zangrando ELETTRA, Basovizza, Trieste
	The FERMI@ELETTRA project is an initiative from ELETTRA, INFM and other Italian institutes, to construct a single-pass FEL user-facility for the wavelength range from 100 nm (12 eV) to 10 nm (124 eV), to be located next to the third-generation synchrotron radiation facility ELETTRA in Trieste, Italy. The project is concentrated around the existing 1.2-GeV S-band linac, i.e., the injector for the storage ring. Presently the linac is only operational for approximately 2 hours per day. The remaining time is available for the construction and operation of an FEL but modifications and operation must be planned such that operation of the storage ring can be guaranteed until the completion of a new full-energy injector (spring 2006). At this moment the FEL project evolves from a conceptional design stage towards a technical design and the actual implementation. Key issues are: incorporation of the free-electron laser in the infrastructure of the Sincrotrone Trieste, adjustments of the linac to facilitate FEL operation, required additional civil engineering, undulator design, FEL seeding options, and beamline design. This paper serves as an overview of the project in combination with a discussion of the critical issues involved.

MOPKF039	The ELETTRA Superconducting Wiggler	booster, linac, vacuum, damping	390
	L. Tosi, C. Knapic, D. Zangrando ELETTRA, Basovizza, Trieste
	A 3.5 Tesla 64 mm period superconducting wiggler has been installed in the ELETTRA storage ring as a photon source for a future X-ray diffraction beamline. After several technological upgrades, a series of measurements were carried out to characterize the device and its effects on the electron beam, such as optics distortion and dynamic aperture. A description of the upgrades and measurements are presented.

MOPKF040	Effect of Electron-beam Feedbacks on the ELETTRA Storage-ring Free-electron Laser	electron, laser, booster, linac	393
	M. Trovò, D. Bulfone, M. Danailov, G. De Ninno, B. Diviacco, V. Forchi', M. Lonza ELETTRA, Basovizza, Trieste L. Giannessi ENEA C.R. Frascati, Frascati (Roma)
	As is well known, the stability of a storage-ring free-electron laser is strongly related to that of the electron beam. With respect to second-generation devices, such as Super ACO and UVSOR, the free-electron laser at ELETTRA is characterized by a noticeably higher gain and, consequently, shows to be much more sensitive to electron-beam instabilities. In order to counteract the impact of such instabilities, both a longitudinal multibunch and a local orbit feedbacks have been implemented for free-electron laser operation. Aim of this paper is to report on the beneficial effect of these feedback systems on the laser performance.

MOPKF041	SPARC Photoinjector Working Point Optimization, Tolerances and Sensitivity to Errors	electron, laser, booster, emittance	396
	M. Ferrario, M.E. Biagini, M. Boscolo, V. Fusco, S. Guiducci, M. Migliorati, C. Sanelli, F. Tazzioli, C. Vaccarezza INFN/LNF, Frascati (Roma) L. Giannessi, L. Mezi, M. Quattromini, C. Ronsivalle ENEA C.R. Frascati, Frascati (Roma) J. Rosenzweig UCLA, Los Angeles, California L. Serafini INFN-Milano, Milano
	A new optimization of the SPARC photoinjector, aiming to reduce the FEL saturation length, is presented in this paper. Start to end simulations show that with 1.1 nC charge in a 10 ps long bunch we can deliver at the undulator entrance a beam having 100 A in 50% of the slices (each slice being 300 mm long) with a slice emittance ?1 mm, thus reducing the FEL-SASE saturation length to 12 m at 500 nm wavelength. In addition the stability of the nominal working point and its sensitivity to various type of random errors, under realistic conditions of the SPARC photoinjector operation, are discussed. A systematic scan of the main parameters around the operating point, performed with PARMELA code interfaced to MATLAB, shows that the probability to get a projected emittance exceeding 1 mm is only 10 % and the slice emittance remains below 1 mm in all cases.

MOPKF042	Status of the SPARC Project	electron, booster, linac, vacuum	399
	M. Ferrario, D. Alesini, M. Bellaveglia, S. Bertolucci, M.E. Biagini, R. Boni, M. Boscolo, M. Castellano, A. Clozza, G. Di Pirro, A. Drago, A. Esposito, D. Filippetto, V. Fusco, A. Gallo, A. Ghigo, S. Guiducci, M. Incurvati, C. Ligi, F. Marcellini, L. Pellegrino, M.A. Preger, R. Ricci, C. Sanelli, M. Serio, F. Sgamma, B. Spataro, A. Stecchi, A. Stella, F. Tazzioli, C. Vaccarezza, M. Vescovi, C. Vicario INFN/LNF, Frascati (Roma) F. Alessandria, A. Bacci, M. Mauri INFN/LASA, Segrate (MI) I. Boscolo, F. Brogli, S. Cialdi, C. De Martinis, D. Giove, C. Maroli, V. Petrillo, M. Romé, L. Serafini INFN-Milano, Milano L. Catani, E.C. Chiadroni, A. Cianchi, S. Tazzari Università di Roma II Tor Vergata, Roma F. Ciocci, G. Dattoli, A. Doria, F. Flora, G.P. Gallerano, L. Giannessi, E. Giovenale, G. Messina, L. Mezi, P.L. Ottaviani, L. Picardi, M. Quattromini, A. Renieri, C. Ronsivalle ENEA C.R. Frascati, Frascati (Roma) D. Dowell, P. Emma, C. Limborg-Deprey, D. Palmer SLAC, Menlo Park, California D. Levi, M. Mattioli, G. Medici Università di Roma I La Sapienza, Roma M. Migliorati, A. Mostacci, L. Palumbo Rome University La Sapienza, Roma P. Musumeci, J. Rosenzweig UCLA, Los Angeles, California M. Nisoli, S. Stagira, S. de Silvestri Politecnico/Milano, Milano
	The aim of the SPARC project is to promote an R&D activity oriented to the development of a high brightness photoinjector to drive SASE-FEL experiments at 500 nm and higher harmonics generation. It has been proposed by a collaboration among ENEA-INFN-CNR-Universita‘ di Roma Tor Vergata-INFM-ST and funded by the Italian Government with a 3 year time schedule. The machine will be installed at LNF, inside an existing underground bunker. It is comprised of an rf gun driven by a Ti:Sa laser to produce 10-ps flat top pulses on the photocathode, injecting into three SLAC accelerating sections. We foresee conducting investigations on the emittance correction and on the rf compression techniques up to kA level. The SPARC photoinjector can be used also to investigate beam physics issues like surface-roughness-induced wake fields, bunch-length measurements in the sub-ps range, emittance degradation in magnetic compressors due to CSR. We present in this paper the status of the design activities of the injector and of the undulator. The first test on diagnostic prototypes and the first experimental achievements of the flat top laser pulse production are also discussed.

MOPKF043	An Ultra-high Brightness, High Duty Factor, Superconducting RF Photoinjector	booster, vacuum, damping, alignment	402
	M. Ferrario INFN/LNF, Frascati (Roma) J. Rosenzweig UCLA, Los Angeles, California J. Sekutowicz DESY, Hamburg
	Recent advances in superconducting rf technology, and an improved understanding of rf photoinjector design optimization make if possible to propose a specific design for a superconducting rf gun which can simultaneously produce both ultra-high peak brightness, and high average current. Such a device may prove to be a critical component of next generation x-ray sources such as self-amplified spontaneous emission free-electron lasers (SASE FEL) and energy recovery linac (ERL) based systems. The design presented is scaled from the present state-of-the-art normal conducting rf photoinjector that has been studied in the context of the LCLS SASE FEL. Issues specific to the superconducing rf photoinjector, such as accelerating gradient limit, rf cavity design, and compatibility with magnetic focusing and laser excitation of a photocathode, are discussed.

MOPKF044	Wake Fields Effects in the Photoinjector of the SPARC Project	booster, vacuum, damping, alignment	405
	V. Fusco, M. Ferrario, B. Spataro INFN/LNF, Frascati (Roma) M. Migliorati, L. Palumbo Rome University La Sapienza, Roma
	When a bunch travels off axis across structures whose shape is not uniform, such as RF cavity or bellows, generates longitudinal and transverse wake fields. In addition transverse time dependent fields (like transverse RF components and wake fields ) may induce correlated slice centroids displacement, so that each slice centroid motion become affected also by space charge forces generated by the next slices. An evaluation of the emittance degradation and induced energy spread in the SPARC injector is performed with an improved version of the code Homdyn and the results are discussed. A comparison with other codes (ABCI, PARMELA 3D) to validate our model is also presented.

MOPKF045	Cesium Telluride and Metals Photoelectron Thermal Emittance Measurements Using a Time-of-flight Spectrometer	booster, emittance, vacuum, damping	408
	D. Sertore, D. Favia, P. Michelato, L. Monaco, P. Pierini INFN/LASA, Segrate (MI)
	The thermal emittance of photoemitted electrons in an RF gun is a crucial parameter for short wavelength FELs and future high luminosity electron colliders. An estimate of the thermal emittance of semiconductor and metal samples, commonly used as photocathodes, has been assessed using a Time-Of-Flight spectrometer. In this paper we present the analysis, based on angle resolved photoemission measurements, of both the cesium telluride (Cs2Te) photocathode films as used at the TESLA Test Facility, and polycrystalline metals. These latter measurements, at different laser wavelengths, are used to validate both our experimental apparatus and the thermal emittance reconstruction technique developed.

MOPKF046	Photoelectron RF Gun Designed as a Single Cell Cavity	gun, emittance, booster, cathode	411
	H. Dewa, T. Asaka, H. Hanaki, T. Kobayashi, A. Mizuno, S. Suzuki, T. Taniuchi, H. Tomizawa, K. Yanagida JASRI/SPring-8, Hyogo J. Sasabe Hamamatsu Photonics K.K., Hamakita, Shizuoka M. Uesaka UTNL, Ibaraki
	The paper describes the recent improvements of S-band RF-gun at SPring-8. The cavity of the gun is a single-cell pillbox, and the copper inner wall is used as a cathode. The electron beam from the cathode was accelerated up to 4.1 MeV at an electric field of 175 MV/m. For emittance compensation, two solenoid magnets were used. A 3m linac and a quadrupole scan emittance diagnostic were added after the RF-gun. The beam energy spread and beam emittance after the linac is presented. The beam emittance measured with quadrupole scan is compered to that measured with double slits just after the RF-gun. For high quantum efficiency, Cs2Te cathode was also tested. It is vacuum sealed in a cartridge-type electric tube and four tubes can be installed in a vacuum chamber behind the cavity. Although the quantum efficiency after RF conditioning for two hours to achieve 90MV/m was 3%, it decreased to 1% after the 28 hours RF conditioning.

MOPKF048	Injection Beam Loss at the SPring-8 Storage Ring	gun, emittance, booster, cathode	417
	M. Takao, T. Ohshima, S. Sasaki, J. Schimizu, K. Soutome, H. Tanaka JASRI/SPring-8, Hyogo
	Capture efficiency of injection beam is extremely important for top-up operation because open photon shutter permits the bremsstrahlung from lost particles to be transported to experimental floor. Furthermore, since the SPring-8 storage ring has many in-vacuum insertion devices with narrow gap, the demagnetization by the lost electron bombardment is also serious to the beam injection with gap closing. To clarify the loss mechanism of injected beam at the SPring-8 storage ring, we investigate the loss process under various conditions of the storage ring, and especially measure the dependence of injection loss rate on gaps of insertion devices. Comparing the measurements with simulations, we found that an injected particle with a large horizontal amplitude begins to oscillate in vertical direction through error magnetic field and eventually disappears at the vertical limit. It is also found that the low chromaticity of the storage ring is effective for the reduction of injection beam loss. In this paper, we report the loss mechanism of the injection beam of the SPring-8 storage ring and the possible improvements of the capture efficiency.

MOPKF049	Design Study for a 205 MeV Energy Recovery Linac Test Facility at the KEK	linac, booster, cathode, insertion	420
	E.-S. Kim PAL, Pohang K. Yokoya KEK, Ibaraki
	We present a lattice and beam dynmics analysis for a 200 MeV energy recovery linac test facility at the KEK. The test facility consists of a photocathode rf gun, a 5 MeV injector, a merger, 200 MeV superconducting linac, TBA sections and beam dump line. Beam parameters and optimal optics to relaize the energy recovery linac are described. Simulation results on emittance growth due to HOMs in the superconducting linac and coherent synchrotron radiation in the designed lattice are presented.

MOPKF050	Current Heart-like Wiggler	wiggler, linac, booster, cathode	423
	V.I.R. Niculescu, G.R. Anda, F. Scarlat INFLPR, Bucharest - Magurele V. Babin INOE, Bucharest C. Stancu, A. Tudorache Bucharest University, Faculty of Physics, Bucharest-Magurele
	A new wiggler structure for free electron lasers is presented. Current hart-like wiggler produced magnetic fields which were spatially periodic. The current wiggler structure was in the shape of stacks of modified circle wires. The current had alternating directions. The magnetic field components for each wire present a C2 symmetry (for a model with 3 branches). The wiggler transverse cross - section in arbitrary units was given by the following expressions: x = R(d+sin(3j))cos(j) , y = R(d+sin(3j))sin(j) , z = constant, where d and R are the parameters. In cylindrical coordinates the Biot - Savart law was evaluated numerically. The magnetic field aspect was mainly transversal and also easily adjusted with the current . The versatility of this structure permits new geometrical forms and developments in the wiggler and wiggler design .

MOPKF052	Design of an In Archromatic Superconducting Wiggler at NSRRC	wiggler, linac, booster, cathode	425
	C.-H. Chang, H.-H. Chen, T.-C. Fan, G.-Y. Hsiung, M.-H. Huang, C.-S. Hwang, F.-Y. Lin NSRRC, Hsinchu
	A 15-pole superconducting wiggler with period length of 6 cm is designed for National Synchrotron Research Center (NSRRC) in Taiwan. The compact superconducting wiggler will be installed near the second bending magnet of the triple bend achromat section in the 1.5 GeV storage ring. This wiggler magnet with maximum peak field of 3.2 T at pole gap width of 19 mm is operated in 4.2 K liquid helium vessel. A 5-pole prototype magnet is tested and measured to verify the magnetic field performance in the testing dewar. Furthermore, the cryogenic considerations and thermal analysis in the 4.2 K wiggler magnet and the 77 K vacuum chamber are also presented in this work.

MOPKF053	Pulsed-wire Method of Field Measurement on Short Elliptically Polarized Undulator	wiggler, linac, booster, cathode	428
	T.-C. Fan, C.-S. Hwang, F.-Y. Lin NSRRC, Hsinchu
	With two sets of photo illuminator and detector, scientists already have applied pulsed-wire method to measure the magnetic field along two mutually perpendicular directions. Two-dimensional pulsed-wire method is useful for the test of elliptically polarlized undulator (EPU). We tried to use this method to observe the first integral and second integral fields of a short EPU in real time during the polarization tuning. We have taken care more details than the pulsed-wire measurement of planner undulators. The phase difference, the relative field strength along two direction as well as the precise centerline can be achieved.

MOPKF054	Generation of Femtosecond Electron Pulses	wiggler, booster, radiation, cathode	431
	S. Rimjaem, V. Jinamoon, K. Kusoljariyakul, J. Saisut, C. Thongbai, T. Vilaithong FNRF, Chiang Mai S. Chumphongphan Mae Fah Luang University, Chiang Rai M.W. Rhodes, P. Wichaisirimongkol IST, Chiang Mai H. Wiedemann SLAC/SSRL, Menlo Park, California
	Femtosecond electron pulses have become an interesting tool for basic and applied applications, especially in time-resolved experiments and dynamic studies of biomolecules. Intense, coherent radiation can be generated in a broad far-infrared spectrum with intensities, which are many orders of magnitude higher than conventional sources including synchrotron radiation sources. At the Fast Neutron Research Facility (FNRF), Chiangmai University (Thailand), the SURIYA project has been established with the aim to produce femtosecond pulses utilizing a combination of a S-band thermionic rf-gun and an alpha-magnet as the magnetic bunch compressor. A specially designed rf-gun has been constructed to obtain the optimum beam characteristics for best bunch compression. Simulation results show that the bunch lengths as short as 50 fs rms can be expected at the experimental station. This rf- gun, an alpha-magnet and a 20 MeV linac with beam transport system were installed and are being commissioned to generate femtosecond electron bunches. To measure the bunch length of the electron pulses, a Michelson interferometer will be used to observe the spectrum of coherent FIR transition radiation via optical autocorrelation. The main results of numerical simulations and experimental results will be discussed in this paper.

MOPKF055	A Study of CSR Induced Microbunching Using Numerical Simulations	wiggler, booster, bunching, cathode	434
	M.A. Bowler, H.L. Owen CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
	Microbunching due to Coherent Synchrotron Radiation (CSR) has been predicted for high density bunches and has been 'observed' using numerical simulations by the code ELEGANT of M. Borland, which includes a 1D model of CSR. However, there is currently a debate as to whether this micro-bunching is a real physical effect or is a numerical artefact, possibly introduced by having to use macro-particles to model the electrons. In particular, the amplitude of the micro-bunching diminishes as the number of macroparticles increases, but the question remains open as to whether the amplitude converges to zero or a finite value. The micro-bunching produced by ELEGANT is being studied as a function of the numerical parameters of the code and also as a function of the range of bunch parameters and bending magnet strengths of relevance to the 180 degree bending arcs required for the proposed 4GLS at Daresbury Laboratory. Calculations with up to 2 million macroparticles have been carried out on a Linux workstation using gaussian bunches of FWHM of 2psec and charge of 1 nC, and show the existence of microbunching at the end of a 180 degree arc containing 5 TBA cells with magnet strengths of 0.5T. Further investigation of this problem is required.

MOPKF056	Injector Design for the 4GLS Energy Recovery Linac Prototype	wiggler, bunching, cathode, gun	437
	C. Gerth, F.E. Hannon CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
	Daresbury Laboratory has been given funding for the construction of an Energy Recovery Linac Prototype (ERLP) that operates at a target electron beam energy of 35 MeV and drives an IR oscillator FEL. The ERLP serves as a test-bed for the study of beam dynamics and accelerator technology important for the design and construction of the proposed 4th Generation Light Source (4GLS). A key component of the ERLP is a high-brightness injector. The injector consists of a DC photocathode gun, which is currently being built at Daresbury Laboratory and based on the design of the gun for the IR demonstrator FEL at Thomas Jefferson National Accelerator Facility. The gun section is followed by a conventional buncher cavity, a super-conducting booster and a transfer line to the main linac. In this paper, the design of the ERLP injector is discussed. The performance of the injector has been studied using the particle tracking code ASTRA.

MOPKF058	Construction of an APPLE-II Type Undulator at Daresbury Laboratory for the SRS	wiggler, bunching, cathode, gun	440
	F.E. Hannon, J.A. Clarke, C. Hill, A.A. Muir, D.J. Scott, B.J.A. Shepherd CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
	A new variable polarisation undulator of the APPLE-II type has been designed and constructed at Daresbury Laboratory. Testing of the 56mm period device has recently started in the new Magnet Test Facility at Daresbury Laboratory. This paper presents the magnetic and mechanical design of the undulator, and the first magnetic measurement results.

MOPLT018	Aperture and Delivery Precision of the LHC Injection System	lepton, wiggler, acceleration, undulator	572
	B. Goddard, M. Gyr, J.-B. Jeanneret, V. Kain, M. Lamont, V. Maire, V. Mertens, J. Wenninger CERN, Geneva
	The main LHC injection elements in interaction regions 2 and 8 comprise the injection septa (MSI), the injection kicker (MKI), together with three families of passive protection devices (TDI, TCDD and TCLI). The apertures of the injection septa for the injected and two circulating beams are detailed with a new enlarged vacuum chamber and final septum alignment. The circulating beam aperture of the TDI is detailed with a new TDI support design and modified vacuum tank alignment. A modified TCDD shape is also presented and the implications for the aperture and protection level discussed. The various errors in the SPS, the transfer lines and the injection system, which contribute to injection errors, are analysed, and the expected performance of the system is derived, in terms of the expected delivery precision of the injected beam.

MOPLT021	Attenuation and Emittance Growth of 450 GeV and 7 TeV Proton Beams in Low-Z Absorber Elements	lepton, wiggler, acceleration, undulator	581
	V. Kain, B. Goddard, Y. Kadi, R. Schmidt CERN, Geneva
	The intensity of the LHC beams will be several orders of magnitude above the damage thresholds for equipment, at 7 TeV, but also already at injection energy of 450 GeV. Passive protection of the equipment against failures during beam transfer, injection and dumping of the beam with absorbers and collimators is foreseen to ensure safe operation. Since these protection devices must be robust in case of beam impact, low-Z materials such as graphite are favored. The reduction of the energy density of the primary beam by the absorber is determined by the attenuation of the beam due to nuclear collisions and the emittance growth of the surviving protons due to scattering processes. Absorbers with low density materials tend to be several meters long to ensure sufficient reduction of the transverse energy density of the impacting beam. The physics principles leading to attenuation and emittance growth for a hadron beam traversing matter are summarised, and FLUKA simulation results for 450 GeV and 7TeV proton beams on low-Z absorbers are compared with theoretical predictions. Design criteria for the LHC absorbers can be derived from these results. As an example, for the transfer line from SPS to LHC a short, low-Z absorber has been proposed to protect the LHC injection elements.

MOPLT022	The Expected Performance of the LHC Injection Protection System	lepton, wiggler, acceleration, undulator	584
	V. Kain, O.S. Brüning, L. Ducimetière, B. Goddard, M. Lamont, V. Mertens CERN, Geneva
	The passive protection devices TDI, TCDD and TCLI are required to prevent damage to the LHC in case of serious injection failures, in particular of the MKI injection kicker. A detailed particle tracking, taking realistic mechanical, positioning, injection, closed orbit and local optical errors into account, has been used to determine the required settings of the absorber elements to guarantee protection against different MKI failure modes. The expected protection level of the combination of TDI with TCLI, with the new TCLI layout, is presented. Conclusions are drawn concerning the expected damage risk level.

MOPLT023	Electron Model of an FFAG Muon Accelerator	lepton, wiggler, undulator, cathode	587
	E. Keil CERN, Geneva J.S. Berg BNL, Upton, Long Island, New York A. Sessler LBNL, Berkeley, California
	Parameters are derived for the lattice and RF system of electron models of a non-scaling FFAG ring for accelerating muons. The models accelerate electrons from about 10 to about 20 MeV, and have circumferences between 10 and 17 m. Magnet types and dimensions, spacings, half apertures, about 12~mm by 20~mm,and number of cells are presented. The magnetic components are compared to existing magnets. The tune variation with momentum covers several integers, similar to that in a full machine, and allows the study of resonance crossing. The consequences of misaligned magnets are studied by simulation. The lattices are designed such that transition is at about 15 MeV. The variation of orbit length with momentum is less than 36~mm, and allows the study of acceleration outside a bucket. A 100~mm straight section, in each of the cells, is adequately long for an RF cavity operating at 3 GHz. Hamiltonian dynamics in longitudinal phase space close to transition is used to calculate the accelerating voltage needed. Acceleration is studied by simulation. Practical RF system design issues, e.g. RF power, and beam loading are estimated.

MOPLT024	Flexibility, Tolerances, and Beam-Based Tuning of the CLIC Damping Ring	lepton, wiggler, undulator, cathode	590
	M. Korostelev, J. Wenninger, F. Zimmermann CERN, Geneva
	The present design of the CLIC damping ring can easily accommodate anticipated CLIC parameter changes. Realistic misalignments of magnets and monitors increase the equilibrium emittance. In simulations we study both the sensitivity to magnet displacements and the emittance recovery achieved by orbit correction, dispersion-free steering and coupling compensation.

MOPLT025	Status and Plans for the SPS to LHC Beam Transfer Lines TI 2 and TI 8	lepton, wiggler, undulator, cathode	593
	V. Mertens, B. Goddard, T. Risselada CERN, Geneva
	Beam transfer from the CERN Super Proton Synchrotron (SPS) to the Large Hadron Collider (LHC) will be done through the two transfer lines TI 2 and TI 8, presently under construction, with a combined length of about 5.6 km. The final layout, optics design and correction scheme for these lines will be presented. The requirement of simultaneously matching their geometry and optics with that of the LHC will be treated, including the methodology for alignment of the elements along the line and a proposed solution in the final matching section. After the commissioning of the short transfer line TT40 just upstream of TI 8 in 2003, beam tests of the whole of TI 8 are scheduled for autumn 2004, with the aim to validate many of the new features and mechanisms involved in the future control and operation of these lines. The status of the installation will be described, comprising the progress with infrastructure, services and line elements. An outlook will be given for the work remaining until 2007.

MOPLT026	Equipment Manufacturing and Test Data Tracking for the LHC	lepton, wiggler, undulator, cathode	596
	E. Manola-Poggioli, S.-A. Chalard, C. Delamare, T. Ladzinski, S. Mallon-Amerigo, P. Martel, S. Petit, T. Pettersson, O. Rademakers Di Rosa, B. Rousseau, A.S. Suwalska, D. Widegren CERN, Geneva
	The MTF system was developed at CERN to capture the design, manufacturing and test data of equipment built for LHC. Today, more than 80.000 descriptions of LHC equipment are managed using the MTF. The system handles both production data and non-conformance issues. The acquisition of the equipment data is both an organisational and a technical challenge. On the organisational side many different aspects of production and management have to be taken into account. The LHC equipment suppliers, wherever their production facilities are located, whatever their computer skills or rates of production are, need a user friendly environment to provide the data with a very limited effort on the shop floor. For expensive equipment such as the LHC dipoles a reliable and robust non-conformance methodology must be put in place, the MTF provides the required information technology support tools. The EDMS Service has developed methods, training processes and tools to cope with an extensive use of the system, a use that will grow during the next years until the LHC is installed. This paper presents the experience acquired and the solutions put in place.

MOPLT027	Cold Beam Vacuum Interconnects for the LHC Insertion Regions	lepton, wiggler, undulator, cathode	599
	D.R. Ramos, D. Chauville, J. Knaster, R. Veness CERN, Geneva
	The LHC machine is composed of arcs and insertion regions where superconducting magnets, working at temperatures of 1.9 K and 4.5 K, have flexibly interconnected beam vacuum chambers. These interconnects must respect strict requirements in terms of impedance, aperture, space optimization and reliability. A complete interconnect design was first developed for the arc regions, and from which a total of 20 variants have been created according to the different functional requirements of each pair of cryostats along the machine. All design features and manufacture processes were validated through extensive testing. Manufacture and assembly cost was minimised by using a modular interconnect design, with common components shared among different design variants. A detailed quality assurance structure was implemented in order to achieve the high level of reliability required. This paper presents the layout of cold beam vacuum interconnects along with details of development and testing performed to validate design and integration.

MOPLT028	In-Situ Vibration Measurements of the CTF2 Quadrupoles	lepton, wiggler, undulator, cathode	602
	S. Redaelli, W. Coosemans CERN, Geneva
	The Compact LInear Collider (CLIC), presently under study at the European Organization for Nuclear Research (CERN), aims at colliding high-energy ‘‘nanobeams'' at a luminosity of 10³⁵ cm^-2s^-1. Vibrations of the lattice elements, if not properly corrected, can result in a loss in performance by creating both unacceptable emittance growth in the linear accelerator and relative beam-beam offsets at the interaction point. Of particular concern are the vibrations induced by the accelerator environment. For example, the circulating water used to cool the lattice quadrupoles will increase magnet vibration levels. In the framework of the CLIC stability study, in-situ measurements of quadrupole vibrations have been performed at the CLIC Test Facility 2 (CTF2) with all accelerator equipment switched on. Since the CTF2 quadrupoles and their alignment support structures are realistic prototypes of those to be used in the CLIC linac, the measurements provide a realistic estimate of the CLIC magnet vibrations in a realistic accelerator working environment.

MOPLT029	All Digital IQ Servo-system for CERN Linacs	lepton, wiggler, undulator, cathode	605
	A. Rohlev, J. Broere, R. Garoby, I. Kozsar, J. Serrano CERN, Geneva
	A VME based control system has been developed and built at CERN for the servo loops regulating the field in linac accelerating structures. It is an all-digital system built on a single VME card, providing digital detection, processing, and modulation. It is foreseen to be used, in different versions, for the needs of both present and future CERN hadron linacs. The first application will be in the energy ramping RF chain of the CERN Heavy Ion Linac (linac 3). In addition to regulating the cavity field, the system incorporates the measurement and control of the cavity resonance as well as an imbedded loop stabilizing the gain and the phase of the final amplifier operating near saturation. The design principle and the experimental results are described.

MOPLT030	Performance Limits and IR Design of a Possible LHC Luminosity Upgrade Based on Nb-Ti SC Magnet Technology	lepton, wiggler, undulator, cathode	608
	F. Ruggiero, O.S. Brüning, R. Ostojic, L. Rossi, W. Scandale, T.M. Taylor CERN, Geneva A. Devred CEA/DSM/DAPNIA, Gif-sur-Yvette
	We investigate the maximum LHC performance for a possible IR design based on classical Nb-Ti insertion magnets. We then extend our analysis to a ternary Nb-based ductile alloy such as Nb-Ti-Ta, a less developed but relatively cheap super-conducting material which would allow us to gain about 1 T of peak field on the coils, and discuss the corresponding luminosity reach for a possible LHC upgrade compared to that based on Nb3Sn magnet technology.

MOPLT031	LHC Abort Gap Filling by Proton Beam	lepton, wiggler, undulator, cathode	611
	E.N. Shaposhnikova, S.D. Fartoukh, J.-B. Jeanneret CERN, Geneva
	Safe operation of the LHC beam dump relies on the possibility of firing the abort kicker at any moment during beam operation. One of the necessary conditions for this is that the number of particles in the abort gap should be below some critical level defined by quench limits. Various scenarios can lead to particles filling the abort gap. The relevant time scales associated with these scenarios are estimated for top energy where the synchrotron radiation losses are not negligible for uncaptured particle motion. Two cases are considered, both with RF on and RF off. The equilibrium distribution of lost particles in the abort gap defines the requirements for maximum tolerable relative loss rate and as a consequence the minimum acceptable longitudinal lifetime of the proton beam in collision.

MOPLT032	Breakdown Resistance of Refractory Metals Compared to Copper	lepton, wiggler, undulator, linac	614
	M. Taborelli, S. Calatroni, M. Kildemo CERN, Geneva
	The behaviour of Mo, W and Cu with respect to electrical breakdown in ultra high vacuum has been investigated by means of a capacitor discharge method. The maximum stable electric field and the field enhancement factor, beta, have been measured between electrodes of the same material in a sphere/plane geometry for anode and cathode, respectively. The maximum stable field increases as a function of the number of breakdown events for W and Mo. In contrast, no systematic increase is observed for Cu. The highest values obtained are typically 500 MV/m for W, 350 MV/m for Mo and only 180 MV/m for Cu. This conditioning, found for the refractory metals, corresponds to a simultaneous decrease of beta and is therefore related to the field emission properties of the surface and their modification upon sparking. Accordingly, high beta values and no applicable field increase occur for Cu even after repeated breakdown. The results are in agreement with rf breakdown experiments [] performed on prototype 30 GHz accelerating structures for the CLIC accelerator. W. Wuensch, C. Achard, S. Döbert, H. H. Braun, I. Syratchev, M. Taborelli, I. Wilson, "A Demonstration of High Gradient Acceleration", CERN-AB-2003-048-RF; CLIC-Note-569, Proc. PAC2003.

MOPLT033	Experimental Studies of Controlled Longitudinal Emittance Blow-up in the SPS as LHC Injector and LHC Test-Bed	lepton, wiggler, undulator, linac	617
	J. Tuckmantel, T. Bohl, T.P.R. Linnecar, E.N. Shaposhnikova CERN, Geneva
	The longitudinal emittance of the LHC beam must be increased in a controlled way both in the SPS and the LHC itself. In the first case a small increase is sufficient to help prevent coupled bunch instabilities but in the second a factor three is required to also reduce intra-beam scattering effects. This has been achieved in the SPS by exciting the beam at the synchrotron frequency through the phase loop of the main RF system using bandwidth-limited noise, a method that is particularly suitable for the LHC which will have only one RF system. We describe the tests that have been done in the SPS both for low and high intensity beams, the hardware used and the influence of parameters such as time of excitation, bandwidth, frequency and amplitude on the resulting blow-up. After taking into account intensity effects it was possible to achieve a controlled emittance increase by a factor of about 2.5 without particle loss or the creation of visible tails in the distribution.

MOPLT034	Possible Causes and Consequences of Serious Failures of the LHC Machine Protection System	lepton, wiggler, undulator, linac	620
	J.A. Uythoven, R. Filippini, B. Goddard, M. Gyr, V. Kain, R. Schmidt, J. Wenninger CERN, Geneva
	The LHC machine protection systems, including the beam dumping system, are designed to ensure that failures leading to serious damage to the LHC during its lifetime are extremely unlikely. These kind of failures have to date been considered as being ?beyond the design case?, for instance requiring a combination of equipment failure and surveillance failure. However, they need to be evaluated to determine the required safety levels of the protection systems. A second objective is to understand if measures can and should be taken to further reduce the probability of such failures, or to minimise their impact. This paper considers various serious failure modes of the different machine protection systems. The probable consequences and possible ameliorating measures of the worst-case scenarios are discussed. The particular case of having a stored beam with an unavailable beam dumping system is mentioned, together with possible actions to be taken in such an event.

MOPLT069	Investigation of Injection for the Low-emittance Lattice with New-6.25 ohm Kicker Magnet System at the Photon Factory	background, wiggler, vacuum, undulator	710
	A. Ueda, K. Harada, Y. Kobayashi, T. Mitsuhashi KEK, Ibaraki
	We installed 6.25ohm traveling-wave kicker magnet in the Photon Factory to obtain a wide acceptance for the injected beam into the low-emittance lattice of the Photon Factory. We investigate the injection for the low-emittance lattice with this 6.25ohm kicker magnet system. Hence we have optical beam diagnostic systems which source point is inside of injection bump, we use this system for the investigation of injection. The pulse shape of the injection bump was measured by the optical beam profile monitor with high-speed gated camera by using a stored beam. The result of pulse shape of injection bump was agreed with the predicted one by using result of magnetic field measurement, and pulse duration was shorter than twice of revolution time. The instantaneous beam profile of injected beam was observed in turn by turn by using the same beam profile monitor system. We measure the turn by turn position of the injected beam from this observation and compare with a simulation. We also observe a smear out of beam oscillation by nonlinear effect from this instantaneous beam profile measurement.

MOPLT070	FFAG as Phase Rotator for the PRISM Project	background, wiggler, vacuum, undulator	713
	A. Sato, M. Aoki, Y. Arimoto, Y. Kuno, M. Yoshida Osaka University, Osaka Y. Iwashita Kyoto ICR, Uji, Kyoto S. Machida, Y. Mori, C. Ohmori, T. Yokoi, K. Yoshimura KEK, Ibaraki S. Ninomiya RCNP, Osaka
	A Fixed Field Alternating Gradient (FFAG) ring will be used as a phase rotator in the PRISM project. We report a design of the PRISM-FFAG in this paper. PRISM stands for "Phase Rotated Intense Slow Muon beam". It is a project to realize a super muon beam, which combines high-intensity, low-energy, narrow energy-spread and high purity. Its aimed intensity is about 10¹¹-10¹² muons per sec. The muon beam will be provided with a low kinetic energy of 20MeV to optimize for the stopped muon experiments. FFAG has some advantageous characteristics to achieve such superb beam. These are a large momentum (longitudinal) acceptance, a wide transverse acceptance with strong focusing, and synchrotron oscillation, which is needed to perform phase rotation. According to simulations, initial energy spread of 20MeV±40% is reduced down to ±6% after 5 turns of muons in the FFAG ring. In the FFAG ring almost all pions decay into muon, hence extracted beam has extremely low pion contamination. A program to construct the PRISM-FFAG ring has been started. It would be completed by the end of JFY 2005.

MOPLT071	EPICS Based Control System for the KOMAC RF System	background, wiggler, vacuum, undulator	716
	J.C. Yoon, J. Choi, K.M. Ha, J.H. Kim, J.M. Kim, J.-W. Lee PAL, Pohang
	This paper presents the RF control system for Korea Multi-purpose Accelerator Complex (KOMAC). KAERI (Korea Atomic Energy Research Institute) has been performing the project named KOMAC. As the 3nd phase of the project, 20MeV proton accelerating structure is under development. The new design is based on the use of VME based Multi-function modules connected to the specific low level RF Controllers(LLRF) via distributed I/O modules and Serial communication modules. The control system was based on EPICS (Experimental Physics and Industrial Control System) from the end of 2003. Installation and commissioning of the RF module is scheduled on 2004. Control system to integrated the RF System to the KOMAC control system is implemented. Hardware, software and various applications are developed to support the operation of RF Control system. This paper EPICS based control system for KOMAC RF

MOPLT072	Effects of Positrons on Relativistic Solitons in Laser-Plasma Interactions	background, wiggler, vacuum, undulator	719
	J.B. Kim, I.S. Ko POSTECH, Pohang, Kyungbuk H. Suk KERI, Changwon
	An extended 1D kinetic model of relativistic solitons by high power lasers in three species plasmas is suggested and it is applied to analysis on the effects of electron-positron pairs on the solitons. Stability condition of the solitons is derived. The range of parameters for the stable solitons are specified in the frequency-temperature plane. With the creation of electron-positron pairs, relativistic solitons appear stable in wider range of frequencies and temperatures. The regions are expanded toward higher values in overall ranges in the frequency-temperature plane. The stability conditions are affected by the density of positrons. The variation of shapes, peak E-field, and width of the solitons by varying the positron density are analyzed. We discuss the implications of the variation in the soliton on the ion accelerations by it.

MOPLT127	Diagnosing the PEP-II Injection System	damping, acceleration, vacuum, electron	833
	F.-J. Decker, M.H. Donald, R.H. Iverson, A. Kulikov, G.C. Pappas, M. Weaver SLAC, Menlo Park, California
	The injection of beam into the PEP-II B-Factory, especially into the High Energy Ring (HER) has some challenges. A high background level in the BaBar Detector has so far inhibited us from trickling charge into the HER similar to the Low Energy Ring (LER). Analyzing the injection system has revealed many issues which could be improved. The injection bump between two kickers was not closed, mainly because the phase advance wasn't exactly 180 degrees and the two kicker strengths were not balanced. Additionally we found reflections which kick the stored beam after the main kick and cause the average luminosity to drop about 3% for a 10 Hz injection rate. The strength of the overall kick is nearly twice as high than the design, indicating a much bigger effective septum thickness. Compared with single beam the background is worse when the HER beam is colliding with the LER beam. This hints that the beam-beam force and the observed vertical blow-up in the HER pushes the beam and especially the injected beam further out to the edge of the dynamic aperture or beyond.

MOPLT128	Lattice Effects due to High Currents in PEP-II	damping, acceleration, vacuum, electron	836
	F.-J. Decker, H. Smith, J.L. Turner SLAC, Menlo Park, California
	The very high beam currents in the PEP-II B-Factory have caused many expected and unexpected effects: Synchrotron light fans move the beam pipe and cause dispersion, higher order modes cause excessive heating, e-clouds around the positron beam blow up its beam size. Here we describe an effect were the measured dispersion of the beam in the Low Energy Ring (LER) is different at high and at low beam currents. The dispersion was iteratively lowered by making anti-symmetric orbit bumps in many sextupole duplets, checking each time with a dispersion measurement where a dispersive kick is generated. This can be done parasitically during collisions. It was a surprise when checking the low current characterization data that there is a change. Subsequent high and low current measurements confirmed the effect. It is located far away from any synchrotron radiation in the middle of a straight (PR12), away from sextupoles and skew quadrupoles and creates a dispersion wave of about 70 mm at high current while at low current it is negligible.

MOPLT129	Identifying Lattice, Orbit, and BPM Errors in PEP-II	damping, acceleration, vacuum, electron	839
	F.-J. Decker SLAC, Menlo Park, California
	The PEP-II B-Factory is delivering peak luminosities of up to 7.4·10³³ 1/cm² 1/s. This is very impressive especially considering our poor understanding of the lattice, absolute orbit and beam position monitor system (BPM). A few simple MATLAB programs were written to get lattice information, like betatron functions in a coupled machine (four all together) and the two dispersions, from the current machine and compare it the design. Big orbit deviations in the Low Energy Ring (LER) could be explained not by bad BPMs (only 3), but by many strong correctors (one corrector to fix four BPMs on average). Additionally these programs helped to uncover a sign error in the third order correction of the BPM system. Further analysis of the current information of the BPMs (sum of all buttons) indicates that there might be still more problematic BPMs.

TUZACH02	Ultra-high Gradient Compact Accelerator Developments	gun, positron, focusing, plasma	74
	G.J.H. Brussaard, M.J. Van der Wiel TUE, Eindhoven
	Continued development of relatively compact, although not quite 'table-top', lasers with peak powers in the range up to 100 TW has enabled laser-plasma-based acceleration experiments with amazing gradients of up to 1 TV/m. In order to usefully apply such gradients to 'controlled' acceleration, various hurdles need to be overcome. The main one is that of well-synchronized injection into a sub-mm to micron wavelength plasma wave. The talk will describe the various physics regimes of laser wakefield acceleration, and the two classes of experiments being pursued. One is that of atmospheric-density plasmas, non-linear wakefields with extreme gradients (hundreds of GV/m)and 'internal injection' of few-femtosecond electron bunches. A second class involves modest-density plasmas,wakefields of order 1 GV/m and external injection of (sub)-ps bunches. The state-of-the-art of these experiments will be covered, including the progress on plasma waveguiding of TW pulses over many diffraction lengths. The talk will also provide an outlook for the coming few years. This part includes proposed schemes for improvements in the area of injection, such as 'all-optical' injection and injection based on GV/m 'pulsed-DC' photoguns.
	Video of talk
	Transparencies

TUPLT065	Beams from RF Ovens and ECR Ion Sources	laser, beamloading, antiproton, 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	laser, beamloading, antiproton, 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	laser, beamloading, antiproton, 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	linac, laser, beamloading, antiproton	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	laser, beamloading, antiproton, 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	laser, beamloading, antiproton, 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	laser, beamloading, antiproton, 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	linac, laser, beamloading, antiproton	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.

TUPLT076	Optimization of Sextupole Strengths in a Storage Ring for Top-up Operation	sextupole, booster, laser, synchrotron	1330
	H. Tanaka, T. Ohshima, K. Soutome, M. Takao, H. Takebe JASRI/SPring-8, Hyogo
	In top-up operation of a light source, electron or positron beams are frequently injected to keep the stored current constant. Closing an injection bump orbit is thus critically important not to disturb precise experiments. However, there are sextupole magnets inside the injection bump in the SPring-8 storage ring and the bump never closes all over the bump amplitude due to the sextupole nonlinearity. To solve the problem, we proposed a scheme based on minimum condition for the injection bump leakage. The scheme only restricts the sextupole strengths within the bump. Introduction of other sextupole families outside the bump can enlarge the dynamic aperture (DA) of the ring with keeping the minimum leakage. To find the best solution, we optimized the sextupole strengths changing the number of sextupole family as a parameter. The simulation shows that addition of two sextupole families sufficiently enlarges DA. Cabling of the sextupole magnets was partly changed in the summer 2003 and the effects of the strength optimization on the bump leakage, injection efficiency and beam lifetime has been investigated experimentally. We present the obtained results compared with the simulations.

TUPLT077	R&D Status of the Fast Extraction Kicker Magnets for the KEK/JAERI 50 GeV Synchrotron	sextupole, extraction, booster, proton	1333
	Y. Shirakabe, Y. Arakaki, T. Kawakubo, Y. Mori, S. Murasugi, E. Nakamura, I. Sakai, M. Tomizawa KEK, Ibaraki
	The 50 GeV proton synchrotron composes the final stage of the high intensity proton accelerator complex now on construction at JAERI/Tokai site as a joint project by KEK and JAERI. In this ring, the proton beam is accelerated from 3 GeV to 50 GeV, and delivered to the experimental facilities through the fast and slow extraction lines. The distinctive feature of the fast extraction line is that the bipolar extraction function will be provided. In normal operations, the beam is extracted toward the inner side of the ring and transported to the facility for the long baseline neutrino oscillation experiment using the Super-Kamiokande detector. In case of emergency, for example, quenches of the superconducting magnets of the neutrino line or malfunctioning of the ring RF systems, the beam is extracted toward the outer side of the ring and sent directly to the abort line with a beam dump at the end. In the current kicker design, the bipolar function will be achieved by the Symmetric Blumlein PFN (SBPFN) system with two switches on both ends. The designed parameters of the fast extraction kicker magnets and the recent hardware R&D status will be described in this paper.

TUPLT078	Study of Impedances and Instabilities in J-PARC	sextupole, extraction, booster, laser	1336
	T. Toyama, K. Ohmi KEK, Ibaraki Y. Shobuda JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
	J-PARC consists of two high intensity proton rings with energies of 3 GeV and 50 GeV. Longitudinal impedances and instabilities, which are caused by beam chamber, cavities, kicker magnets and others, are mainly discussed in this paper.

TUPLT079	Opposite Field Septum Magnet System for the J-PARC 50GeV Ring Injection	septum, sextupole, booster, laser	1339
	I. Sakai, Y. Arakaki, K. Fan, Y. Mori, M. Muto, Y. Saitou, Y. Shirakabe, M. Tomizawa, M. Uota KEK, Ibaraki K. Gotou, Y. Morigaki, A. Nishikawa, M. Takahashi IHI/Yokohama, Kanagawa H. Mori, A. Tokuchi NICHICON, Shiga
	For the injection/extraction system of the high energy high intensity proton synchrotrons, high field wide aperture thin septum magnets are required. To solve these tight problems, new design concept of opposite-field septum magnet system has been invented. The same grade of opposite magnetic field is produced both inside and outside of the septum. The electromagnetic force and leakage flux around the septum conductor are cancelled out each other. The magnetic field of the circulating beam side is compensated by two sub-bending magnets set on the up-stream and down-stream of the opposite fields septum magnet. The beam-separation angle per magnet length is twice as large as normal septum magnet and the two sub-bending magnets also have a role to extend the injection/extraction angle. The newly developed method of the opposite field septum magnets system.is applied to the injection septum magnets for the J-PARC 50-GeV proton synchrotron to get the sufficient injection angle and clearance for low loss injection. The thin septum thickness and larger kick angle at the septum magnet can be obtained by the new system, which is applicable to many accelerators.

TUPLT132	Investigation of Injection through Bending Magnet Fringe Fields in X-rays Source NESTOR	linac, gun, booster, optics	1434
	A. Mytsykov, P. Gladkikh, A.V. Rezaev, A.Y. Zelinsky NSC/KIPT, Kharkov
	In paper injection in the X-rays source NESTOR through fringe fields of a bending magnet is considered. The simulation of a motion of a beam of charged particles through 3-d fields of magnetic devices of the injection channel, which ones is located on a ring, are performed. The focusing properties of the injection channel are determined.

TUPLT133	Test Results of Injector Based on Resonance System with Evanescent Oscillations	linac, booster, bunching, optics	1437
	S.A. Perezhogin, M.I. Ayzatskiy, E.Z. Biller, K. Kramarenko, V.A. Kushnir, V.V. Mytrochenko, Z.V. Zhiglo NSC/KIPT, Kharkov
	Report presents results of tune-up and tests of the compact electron S ? band injector consisting of the low-voltage diode electron gun and the bunching system based on the resonant system with the evanescent oscillation. In the considered bunching system electrical field increased from beam entrance to an exit of the buncher. The injector designed for bunching of electron beam with initial energy of 25 keV and pulse current of 300 mA and accelerating it to the energy of 1 MeV.

TUPLT137	Comparative Simulation Studies of Electron Cloud Build-up for ISIS and Future Upgrades	target, linac, bunching, optics	1446
	G. Bellodi CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
	Electron cloud effects currently limit the performance of several proton accelerators operating with high beam current. Although ISIS, the 160 kW 70-800 MeV proton synchrotron at the Rutherford Appleton Laboratory (UK), has never appeared to be affected by the problem in its 15 years of operations, e-p instabilities could potentially be a cause of concern for future machine upgrades to higher beam powers. In this paper we review the present status of simulations for ISIS and compare it to preliminary results for two upgrade options: a 0.5MW 180-800 MeV scheme and a 1MW 0.8-3 GeV scheme with an additional synchrotron using ISIS as a booster (see C. Prior et al., ISIS megawatt upgrade plans, in Proceedings of the 2003 Particle Accelerator Conference PAC 2003, Portland, Or, USA).

TUPLT138	A Fast Beam Chopper for Next Generation High Power Proton Drivers	target, bunching, optics, focusing	1449
	M.A. Clarke-Gayther CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
	The identification and development of a successful beam chopper design is regarded as key for the European Spallation Source (ESS), and for all next generation high intensity proton driver schemes that adopt the linac-accumulator ring configuration. A description is given of refinements to the beam line design of a 'Tandem' chopper system, developed to address the requirements of the ESS. Particle tracking using the 'General Particle Tracer' (GPT) code has enabled efficient optimisation of beam apertures, and the analysis of beam power density distributions on chopper beam dumps. Preliminary results of 'proof of principle' testing on prototype fast, and slower transition high voltage pulse generators, are presented.

TUPLT139	Extending the Duty Cycle of the ISIS H Minus Ion Source, Thermal Considerations	target, bunching, optics, ion	1452
	D.C. Faircloth, J.W.G. Thomason CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
	The ISIS H minus ion source is currently being developed on the Ion Source Development Rig (ISDR) at Rutherford Appleton Laboratory (RAL) in order to meet the requirements for the next generation of high power proton drivers. One key development goal is to increase the pulse width and duty cycle, but this has a significant effect on ion source temperatures if no other changes are made. A Finite Element Analysis (FEA) model has been produced to understand the steady state and dynamic thermal behavior of the source, and to investigate the design changes necessary to offset the extra heating.

TUPLT140	Redesign of the ISIS Main Magnet Power Supply Storage Choke	target, bunching, optics, ion	1455
	A.J. Kimber, J.W. Gray, A. Morris CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
	The ISIS facility, based at the Rutherford Appleton Laboratory in the UK, provides intense pulsed neutron and muon beams for condensed matter studies. As part of the facilities upgrade and refurbishment program, the 1MJ storage choke which forms part of the main magnet power supply system, will be replaced with a number of smaller units. The present storage choke, which consists of a split secondary winding transformer, is incorporated into a series-parallel resonant circuit known as the 'white circuit'. This circuit ensures that each magnet receives identical currents, but is not subjected to excessive voltages. Although the storage choke is essentially a transformer, its secondary magnetising inductance is relatively low and a precisely defined value. This paper discusses the design and development of ten smaller units which will eventually replace the present equipment, and the testing of a one fifth scale model, which will be used to prove the technology.

TUPLT141	The Effect of Extraction Geometry on the Measured ISIS H Minus Ion Source Beam	target, bunching, beamloading, lattice	1458
	J.W.G. Thomason, D.C. Faircloth, R. Sidlow, C.M. Thomas, M. Whitehead CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
	Recent Finite Element Analysis (FEA) electromagnetic modelling of the extraction region of the ISIS H minus source has suggested that the present set up of extraction electrode and 90 degree sector magnet is sub-optimal, with the result that the beam profile is asymmetric, the beam is strongly divergent in the horizontal plane and there is severe aberration in the focusing in the vertical plane. The FEA model of the beam optics has demonstrated that relatively simple changes to the system should produce a dramatic improvement in performance. These changes have been incorporated on the Ion Source Development Rig (ISDR) at Rutherford Appleton Laboratory (RAL), and their effects on the H minus beam are presented here.

TUPLT142	Status of Design of Muon Beamline for the Muon Ionisation Cooling Experiment	target, bunching, beamloading, lattice	1461
	K. Tilley CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
	The MICE collaboration proposes to install a Muon Ionisation Cooling Experiment at the ISIS facility, at Rutherford Appleton Laboratory. This experiment will be the first demonstration of ionisation cooling as a means to reduce the large transverse emittance of the muon beam, produced during the early stages of a neutrino factory. In order to permit a realistic demonstration of cooling, a source of muons must be produced, possessing particular qualities, notably in emittance and momenta. This paper describes the present design for the muon beamline source, and the plans for its implementation at RAL.

TUPLT143	Studies of Beam Loss Control on the ISIS Synchrotron	target, bunching, beamloading, lattice	1464
	C.M. Warsop CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
	The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. The ISIS 800 MeV Proton Synchrotron presently provides up to 2.5·10¹³ protons per pulse at 50 Hz, corresponding to a mean power of 160 kW. A dual harmonic RF system upgrade is expected to increase the intensity and power by about 50%. The tighter constraints expected for higher intensity running are motivating a detailed study of beam loss distributions and the main factors affecting their control. Main aims are maximising the localisation of activation in the collector straight, and minimising risk of damage to machine components. The combination of experimental work, developments of the loss measurement systems, and simulation studies are summarised. Key factors considered include: the effects of primary collector geometry and material; the nature of the beam loss; and methods for experimentally determining spatial loss distributions.

TUPLT144	Upgrade of the ISIS Main Magnet Power Supply	target, bunching, beamloading, lattice	1467
	S. West, J.W. Gray, A. Morris CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
	ISIS, situated at the Rutherford Appleton Laboratory (RAL) is the world?s most powerful pulsed neutron source. At the heart of the ISIS accelerator is a proton synchrotron which uses a ring of magnets connected in series and configured as a ?White Circuit?. The magnets are connected in series with capacitor banks so that they form a resonant circuit with a fundamental frequency of 50 Hz. The circuit allows the magnets to be fed with an AC current superimposed on a DC current. The AC is currently provided by a 1MVA Motor-Alternator set and it is now proposed to replace this by a solid state UPS (Uninterruptible Power Supply) system. Tests on a smaller 80kVA unit have shown that it is possible to control the magnet current with a modified UPS system in such a way that both the frequency, phase and output voltage are under the direct influence of the control system. This paper discusses the issues surrounding the upgrading of AC supply to the main magnets with a view to improving the system reliability, improving magnet current stability and reducing the risk of mains failure.

TUPLT145	Transverse Coupling Measurement using SVD Modes from Beam Histories	target, bunching, beamloading, antiproton	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, beamloading, antiproton	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, beamloading, antiproton	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, beamloading, antiproton	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, beamloading, antiproton	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.

TUPLT151	Status of the Fermilab Electron Cooling Project	electron, target, bunching, beamloading	1485
	J.R. Leibfritz, D.R. Broemmelsiek, A.V. Burov, K. Carlson, B. Kramper, T. Kroc, M. McGee, S. Nagaitsev, L. Nobrega, G. Saewert, C.W. Schmidt, A.V. Shemyakin, M. Sutherland, V. Tupikov, A. Warner Fermilab, Batavia, Illinois G. Kazakevich BINP SB RAS, Novosibirsk S. Seletsky Rochester University, Rochester, New York
	Fermilab has constructed and commissioned a full-scale prototype of a multi-MV electron cooling system to be installed in the 8.9 GeV/c Fermilab Recycler ring. This prototype was used to test all of the electron beam properties needed for cooling. However, because the prototype is not located within proximity of the Recycler ring, the actual electron cooling of antiprotons can not be demonstrated until it is relocated. The Fermilab electron cooling R&D project is scheduled to be completed in May, 2004 at which time it will be disassembled and relocated to a newly constructed facility where it will be installed in the Recycler. This paper describes the experimental results obtained with the prototype cooler system, gives an overview of the new electron cooling facility, and discusses the overall status of the project.

TUPLT153	Orbit Response Matrix Analysis Applied at PEP-II	electron, target, lattice, bunching	1488
	C. Steier, A. Wolski LBNL/AFR, Berkeley, California S. Ecklund, J.A. Safranek, P. Tenenbaum, A. Terebilo, J.L. Turner, G. Yocky SLAC, Menlo Park, California
	Beam-based techniques to study lattice properties have proven to be a very powerful tool to optimize the performance of storage rings. The analysis of orbit response matrices has been used very successfully to measure and correct the gradient and skew gradient distribution in many accelerators. The first applications were mostly in synchrotron light sources, but the technique is also used increasingly at colliders. It allows determination of an accurately calibrated model of the coupled machine lattice, which then can be used to calculate the corrections necessary to improve coupling, dynamic aperture and ultimately luminosity. At PEP-II, the Matlab version of LOCO has been used to analyze coupled response matrices for both the LER and the HER. The large number of elements in PEP-II and the very complicated interaction region present unique challenges to the data analysis. The orbit response matrix analysis will be presented in detail, as well as results of lattice corrections based on the calibrated machine model.

TUPLT154	Aperture Studies for the Fermilab AP2 Anti-proton Line	electron, bunching, beamloading, antiproton	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.

TUPLT156	Progress in Ideal High-intensity Unbunched Beams in Alternating Gradient Focusing Systems	electron, focusing, bunching, beamloading	1494
	R. Bhatt, C. Chen, J. Zhou MIT/PSFC, Cambridge, Massachusetts
	A persistent challenge in high-intensity accelerator design is the optimization of matching conditions between a beam injector and a focusing system in order to minimize non-laminar flows, envelope oscillations, emittance growth, and halo production. It has been shown [] that the fluid motion of a thin space-charge dominated beam propagating through a linear magnetic focusing channel consisting of any combination of uniform or periodic solenoidal fields and alternating gradient quadrupole fields can be solved by a general class of corkscrewing elliptic beam equilibria. The present work extends this discussion to asymmetric PPM focusing and derives conditions under which a uniform density elliptical beam can be matched to such a focusing channel by considering the fluid equilibrium in the paraxial limit. Methods of constructing such a beam are also discussed, with particular attention devoted to analytic electrode design for Pierce-type gun diodes of elliptical cross-section. Several applications are discussed, including heavy-ion fusion and a high-efficiency ribbon beam microwave amplifier for accelerator applications. C. Chen, R. Pakter, R. Davidson, "Ideal Matching of Heavy Ion Beams," Nucl. Inst. And Methods, A 464 (2001) p. 518-523

TUPLT159	First Commissioning Experiments at DARHT-II	focusing, bunching, beamloading, antiproton	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.

TUPLT160	Development of a 25-mA, 12% Duty Factor (df) H^- Source for LANSCE	focusing, bunching, emittance, beamloading	1500
	G. Rouleau, A. Arvin, E. Chacon-Golcher, E. Geros, G. Jacobson, J. Meyer, P. Naffziger, S. Schaller, J.D. Sherman, J. Stelzer, J. Zaugg LANL/LANSCE, Los Alamos, New Mexico
	Present operations at the Los Alamos Neutron Science Center (LANSCE) accelerator use a surface conversion source to provide 80-keV, 16 to 18-mA H^- beams with typical rms normalized emittance of 0.13 (pmm-mrad). Operational flexibility of the 800-MeV linac and proton storage ring will be increased by a higher current H^- source. The present goal is to achieve a 25-mA H^- surface converter source with modest (10-20%) emittance increase without sacrificing the present LANSCE production source 12% df and 28 day lifetime. The LANSCE 80-kV ion source test stand (ISTS) has been brought into reliable 24-hour per day operation with computer control and modern electronics. A fourth production source has been fabricated, and is now operating on the ISTS. H^- currents up to 25mA have been observed with 0.15 to 0.18(pmm-mrad) rms normalized emittances. An experimental study of surface converter geometries and electron filters at the emitter electrode are planned to optimize source current and emittance.

TUPLT161	Normal Form Analysis of Linear Beam Dynamics in a Coupled Storage Ring	focusing, bunching, betatron, emittance	1503
	M. Woodley SLAC/NLC, Menlo Park, California A. Wolski LBNL/AFR, Berkeley, California
	The techniques of normal form analysis, well known in the literature, can be used to provide a straightforward characterization of linear betatron dynamics in a coupled lattice. Here, we consider both the beam distribution and the betatron oscillations in a storage ring. We find that the beta functions for uncoupled motion generalize in a simple way to the coupled case. Defined in the way that we propose, the beta functions remain well behaved (positive and finite) under all circumstances, and have essentially the same physical significance for the beam size and betatron oscillations as in the uncoupled case. Application of this analysis to the online modeling of the PEP-II rings is also discussed.

TUPLT162	Computation of the Longitudinal Space Charge Effect in Photoinjectors	focusing, bunching, betatron, beamloading	1506
	C. Limborg-Deprey, P. Emma, Z. Huang, J.J. Welch, J. Wu SLAC, Menlo Park, California
	The LCLS Photoinjector produces a 100A, 10 ps long electron bunch which is later compressed down to 100 fs to produce the peak current required for producing SASE radiation. SASE saturation will be reached in the LCLS only if the emittance and uncorrelated energy spread remain respectively below 1.2 mm.mrad and 5. 10^-4. This high beam quality will not be met if the Longitudinal Space Charge (LSC) instability develops in the injector and gets amplified in the compressors. The Longitudinal Space Charge instability originates in the injector beamline, from an initial modulation of the current density. Numerical computations, performed with Multiparticle Space Charge tracking codes, showing the evolution of the longitudinal phase space along the LCLS Photoinjector beamline, are presented. Those results are compared with an analytical model for various regimes of energy and acceleration. This study justifies the necessity to insert a "laser heater" in the LCLS Photoinjector beamline to warm up the beam and thus prevent the amplification of the LSC instability in the compressors. Numerical calculations of the 'laser heater' performances are presented.

TUPLT163	Achieving Beam Quality Requirements for Parity Experiments at Jefferson Lab	focusing, electron, bunching, betatron	1509
	Y.-C. Chao, H. Areti, F.J. Benesch, B. Bevins, S.A. Bogacz, S. Chattopadhyay, J.M. Grames, J. Hansknecht, A. Hutton, R. Kazimi, L. Merminga, M. Poelker, Y. Roblin, M. Tiefenback Jefferson Lab, Newport News, Virginia D. Armstrong The College of William and Mary, Williamsburg D. Beck, K. Nakahara University of Illinois, Urbana K. Paschke University of Massachusetts, Amherst M. Pitt Virginia Polytechnic Institute and State University, Blacksburg
	Measurement of asymmetry between alternating opposite electron polarization in electron-nucleon scattering experiments can answer important questions about nucleon structures. Such experiments impose stringent condition on the electron beam quality, and thus the accelerator used for beam creation and delivery. Of particular concern to such ?parity? experiments is the level of correlation between beam characteristics (orbit, intensity) and electron polarization that can obscure the real asymmetry. This can be introduced at the beam forming stage, created due to scraping, or not damped to desired level due to defective transport. Suppression of such correlation thus demands tight control of the beam line from cathode to target, and requires multi-disciplined approach with collaboration among nuclear physicists and accelerator physicists/engineers. The approach adopted at Jefferson Lab includes reduction of correlation source, improving low energy beam handling, and monitoring and correcting global transport. This paper will discuss methods adopted to meet the performance criteria imposed by parity experiments, and ongoing research aimed at going beyond current performance.

TUPLT164	CEBAF Injector Achieved World's Best Beam Quality for Three Simultaneous Beams with a Wide Range of Bunch Charges	focusing, bunching, betatron, beamloading	1512
	R. Kazimi, K. Beard, F.J. Benesch, A. Freyberger, J.M. Grames, T. Hiatt, A. Hutton, G.A. Krafft, L. Merminga, M. Poelker, M. Spata, M. Tiefenback, B.C. Yunn, Y. Zhang Jefferson Lab, Newport News, Virginia
	The CEBAF accelerator simultaneously provides three 499 MHz interleaved continuous electron beams spanning 5 decades in beam intensity (a few nA to 200 uA) to three experimental halls. The typical three-user physics program became more challenging when a new experiment, G0, was approved for more than six times higher bunch charge than is routine. The G0 experiment requires up to 8 million electrons per bunch (at a reduced repetition rate of 31 MHz) while the lowest current hall operates at 100 electrons per bunch simultaneously. This means a bunch destined to one hall may experience significant space charge forces while the next bunch, for another hall, is well below the space charge limit. This disparity in beam intensity is to be attained while maintaining best ever values in the beam quality, including final relative energy spread (<2.5x 10^-5 rms) and transverse emittance (<1 mm-mrad norm. rms). The difficulties related to space charge emerge in the 10m long, 100 keV section of the CEBAF injector during initial beam production and acceleration. A series of changes were introduced in the CEBAF injector to meet the new requirements, including changes in the injector setup, adding new magnets, replacing lasers used for the photocathode and modifying typical laser parameters, stabilizing RF systems, and changes to standard operating procedures. In this paper, we will discuss all these modifications in some detail including the excellent agreement between the experimental results and detailed simulations. We will also present some of our operational results.

TUPLT165	A PARMELA Model of the CEBAF Injector valid over a Wide Range of Parameters	focusing, bunching, betatron, beamloading	1515
	Y. Zhang, K. Beard, F.J. Benesch, Y.-C. Chao, A. Freyberger, J.M. Grames, R. Kazimi, G.A. Krafft, R. Li, L. Merminga, M. Poelker, M. Tiefenback, B.C. Yunn Jefferson Lab, Newport News, Virginia
	A pre-existing PARMELA model of the CEBAF injector has been recently verified using machine survey data and also extended to 60 MeV region. The initial distribution and temperature of an electron bunch are determined by the photocathode laser spot size and emittance measurements. The improved injector model has been used for extensive computer simulations of the simultaneous delivery of the Hall A beam required for a hypernuclear experiment, and the Hall C beam, required for a parity experiment. The Hall C beam requires a factor of 6 higher bunch charge than the Hall A beam, with significantly increased space charge effects, while the Hall A beam has an exceedingly stringent energy spread requirement of 2.5x 10^-5 rms. Measurements of the beam properties of both beams at several energies (100 keV, 500 keV, 5 MeV, 60 MeV) and several values of the bunch charge were performed using the standard quad-wire scanner technique. Comparisons of simulated particle transmission rate, longitudinal beam size, transverse emittance and twiss parameters, and energy spread against experimental data yield reasonably good agreement. The model is being used for searching for optimal setting of the CEBAF injector.

TUPLT166	Beam Invariants for Diagnostics	focusing, bunching, betatron, beamloading	1518
	V.V. Danilov, A.V. Aleksandrov ORNL/SNS, Oak Ridge, Tennessee
	This paper deals with some measurable quantities of beams preserved under symplectic transformations. General beam distributions have no determined area, and rms quantities of the beam do not provide invariants in general nonlinear case. It is shown, though, that in the 1D case there exist some integral and local invariants, directly linked to Liouville's theorem. Beam invariants, related to general properties of symplectic transformations, are also found and presented for 2D and 3D cases. If measured at different locations, they can tell whether the transformation is symplectic or there exist diffusion, friction, or other non-Hamiltonian dynamic processes in the beam.

TUPLT167	Installation of the Spallation Neutron Source (SNS) Warm Linac	focusing, linac, bunching, betatron	1521
	P.E. Gibson, C. Deibele, J.J. Error, G.A.J. Johnson, P. Ladd ORNL/SNS, Oak Ridge, Tennessee N.K. Bultman LANL, Los Alamos, New Mexico
	The Spallation Neutron Source (SNS) is an accelerator-based neutron source being built at Oak Ridge National Laboratory. The SNS project design and construction is a partnership involving six DOE national laboratories including Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Oak Ridge, and Los Alamos. When completed in 2006, the SNS will provide the most intense, pulsed neutron beams in the world for scientific research and industrial development. At the present time we are installing and commissioning the warm linac system, designed by Los Alamos, and have to date had good success. The warm linac is comprised of six Drift Tube Linac (DTL) tanks and four Coupled Cavity Linac (CCL) modules. These accept an incoming negative hydrogen ion beam from the Front End injector at 2.5 MeV, and accelerate to a final energy of 185 MeV. At this time we have installed and commissioned DTL tanks 1-3 and installed CCL module 1 . Experience and information gained during installation will be presented. The performance in terms of alignment, vacuum and field tuning will be described.

TUPLT168	SNS Beam Commisioning Status	focusing, linac, bunching, betatron	1524
	S. Henderson, A.V. Aleksandrov, S. Assadi, W. Blokland, C. Chu, S.M. Cousineau, V.V. Danilov, G.W. Dodson, J. Galambos, M. Giannella, D.-O. Jeon, S. Kim, L.V. Kravchuk, M.P. Stockli, E. Tanke, R.F. Welton, T.L. Williams ORNL/SNS, Oak Ridge, Tennessee
	The Spallation Neutron Source accelerator systems will provide a 1 GeV, 1.44 MW proton beam to a liquid mercury target for neutron production. The accelerator complex consists of an H^- injector capable of producing 38 mA peak current, a 1 GeV linear accelerator, an accumulator ring and associated transport lines. The linear accelerator consists of a Drift Tube Linac, a Coupled-Cavity Linac and a Superconducting Linac which provide 1.5 mA average current to the accumulator ring. The staged beam commissioning of the accelerator complex is proceeding as component installation progresses. In three separate beam commissioning runs, the H^- injector and Drift Tube Linac tanks 1-3 have been commissioned at ORNL. Several important performance goals have been achieved, namely 38 mA peak beam current, 1 msec beam pulse length and 1 mA average beam current. Results and status of the beam commissioning program will be presented.

WEPLT028	High-intensity and High-density Charge-exchange Injection Studies into the CERN PS Booster at Intermediate Energies	focusing, acceleration, booster, bunching	1888
	M. Martini CERN, Geneva C.R. Prior CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
	For the high brilliance LHC ultimate beam and the high intensity CNGS beam, single batch injections into the CERN Proton Synchrotron (PS) will be used to increase the overall machine intensity compared with the present double batch injections. Charge-exchange injection into the PS Booster with a new linac at intermediate energies is thus examined. A key parameter to consider is the energy dependence of beam incoherent tune shifts at injection. Increasing the linac energy from the present 50 MeV to 160 MeV should yield a safer tune shift. For each PS Booster ring, a charge-exchange injection scheme is envisaged inside a proper straight section, redesigned with new bends to make a local bump and using the existing fast bump magnets for horizontal phase-space painting. ACCSIM simulations for charge-exchange injection at 160 MeV have been investigated for both LHC and CNGS beams. After optimizing the parameters that are used for the space charge tracking routines, the results of the simulations agree well with expectations, signifying that the LHC ultimate and CNGS beams may be provided with single PS Booster batches within the required emittances. For assessment, simulation of injection at 50 MeV for the current LHC beam has been performed, yielding a fairly good agreement with measured performance. Concurrently, similar charge-exchange injection simulations have been carried out using an alternative programme developed at the Rutherford Appleton Laboratory.

WEPLT029	Intensity Dependent Emittance Transfer Studies at the CERN Proton Synchrotron	focusing, acceleration, resonance, booster	1891
	E. Métral, C. Carli, M. Giovannozzi, M. Martini, R.R. Steerenberg CERN, Geneva G. Franchetti, I. Hofmann GSI, Darmstadt J. Qiang LBNL, Berkeley, California R.D. Ryne LBNL/CBP, Berkeley, California
	An intensive study has been undertaken since the year 2002 to understand better the various high-intensity bottlenecks of the CERN Proton Synchrotron machine. One of these limitations comes from the so-called Montague resonance. High-intensity proton synchrotrons, having larger horizontal than vertical emittance, may suffer from this fourth-order coupling resonance driven by space charge only. In particular, such resonance may lead to emittance sharing and, possibly, beam loss due to vertical acceptance limitation. Experimental observations made in the 2002 and 2003 runs on the Montague resonance are presented in this paper and compared with 3D particle-in-cell simulation results and theoretical predictions.

WEPLT082	General Performances of the Injection Scheme into the SOLEIL Storage Ring	impedance, antiproton, 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	antiproton, 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	antiproton, 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	impedance, antiproton, 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	impedance, antiproton, 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	impedance, antiproton, 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.

THOACH03	Top-up Operation at SPring-8 - Towards Maximizing the Potential of a 3rd Generation Light Source	wakefield, collider, beamloading, beamlosses	222
	H. Tanaka, T. Aoki, T. Asaka, S. Daté, K. Fukami, Y. Furukawa, H. Hanaki, N. Hosoda, T. Kobayashi, N. Kumagai, M. Masaki, T. Masuda, S. Matsui, A. Mizuno, T. Nakamura, T. Nakatani, T. Noda, T. Ohata, H. Ohkuma, T. Ohshima, M. Oishi, S. Sasaki, J. Schimizu, M. Shoji, K. Soutome, M. Suzuki, S. Suzuki, S. Takano, M. Takao, T. Takashima, H. Takebe, K. Tamura, R. Tanaka, T. Taniuchi, Y. Taniuchi, K. Tsumaki, A. Yamashita, K. Yanagida, H. Yonehara, T. Yorita JASRI/SPring-8, Hyogo M. Adachi, K. Kobayashi, M. Yoshioka SES, Hyogo-pref.
	Top-up operation maximizes research activities in a light source facility by an infinite beam lifetime and photon beam stability. We have been improving the SPring-8 accelerators to achieve the ideal top-up operation. For the perturbation-free injection, we adjusted the magnetic field shape of four bump magnets to close the bump orbit, and introduced a scheme to suppress the stored beam oscillation induced by the nonlinearlity of sextupole magnets. These reduced the horizontal oscillation down to a third of the stored beam size. For the loss-free injection, beam collimators were installed upstream of the injection line. This realized the injection efficiency of ~100% under the restricted gap condition of in-vacuum insertion devices (ID). Since autumn 2003, we have been injecting the beams keeping the photon beam shutters opened and ID gaps closed. We developed a bunch-by-bunch feedback system to reduce the beam loss further with all the ID gaps fully closed by lowering the operating chromaticity. The operation with constant stored current is scheduled in June 2004. We present the overview and progress of the SPring-8 top-up operation focusing on our developments and results.
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THYCH01	Issues and Challenges for Short Pulse Radiation Production	electron, wakefield, collider, beamloading	225
	P. Emma SLAC/ARDA, Menlo Park, California
	A new generation of light sources are being planned at many locations, pushing the frontiers of brightness, wavelength, and peak power well beyond existing 3rd generation sources. In addition to these large scale improvements there is great interest in extremely short duration pulses into the femtosecond and sub-femtosecond regime. Collective electron bunch instabilities at these scales are severe, especially in consideration of the high-brightness electron bunch requirements. Several new schemes propose very short radiation pulses generated with moderate electron bunch lengths. Such schemes include radiation pulse compression, differential bunch spoiling, staged high-gain harmonic generation, and selective pulse seeding schemes. We will describe a few of these ideas and address some of the electron bunch length limitations, highlighting recent measurements at the Sub-Picosecond Pulse Source (SPPS) at SLAC where <100-fs electron and x-ray pulses are now available.
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THOBCH01	The Beijing Electron-positron Collider and its Second Phase Construction	collider, synchrotron, radiation, wakefield	230
	C. Zhang, J.Q. Wang IHEP Beijing, Beijing
	The Beijing Electron-Positron Collider (BEPC) was constructed for both high energy physics and synchrotron radiation researches. As an e⁺e^- collider operating in the tau-charm region and a first synchrotron radiation source in China, the machine has been well operated for 14 years since it was put into operation in 1989. As a collider, the peak luminosity of the BEPC has reached its design goal of 510³⁰ cm^-2s^-1 at J/sai energy of 1.55 GeV and 110³¹ cm^-2s^-1 at 2 GeV respectively. The main parameters in the dedicated synchrotron radiation operation are: E=2.2~2.5 GeV, ex0=80 mm mrad at 2.2 GeV, Ib=140 mA and the beam lifetime of 20~30 hours. As the second phase project of the BEPC, the BEPCII , has been approved with total budget of 640 million RMB. The construction is started in the beginning of 2004 and is scheduled to complete by the end of 2007. The BEPCII is a double ring machine with its luminosity goal of 1*10³³ cm^-2s^-1 at 1.89 GeV, two orders of magnitude higher than present BEPC. The BEPCII will operate in the beam energy of 1-2.1 GeV so that its physical potential in the whole t and charm range is preserved, while the collider will be optimized at 1.89 GeV. The upgrading of the collider should also provide an improved SR performance with higher beam energy and intensity. The beam currents will be increased to 250 mA at E=2.5 GeV for the dedicated synchrotron radiation operation of the BEPCII. Some key technologies, such as superconducting RF system, low impedance vacuum devices, superconducting micro-beta quadrupoles and etc., has been intensively studied in order to achieve the target of the BEPCII.
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THOBCH02	DAFNE Operation with the FINUDA Experiment	synchrotron, radiation, wakefield, beamloading	233
	C. Milardi, D. Alesini, G. Benedetti, M.E. Biagini, C. Biscari, R. Boni, M. Boscolo, A. Clozza, G.O. Delle Monache, G. Di Pirro, A. Drago, A. Gallo, A. Ghigo, S. Guiducci, M. Incurvati, C. Ligi, F. Marcellini, G. Mazzitelli, L. Pellegrino, M.A. Preger, P. Raimondi, R. Ricci, U. Rotundo, C. Sanelli, M. Serio, F. Sgamma, B. Spataro, A. Stecchi, A. Stella, C. Vaccarezza, M. Vescovi, M. Zobov INFN/LNF, Frascati (Roma)
	DAFNE operation restarted in September 2003, after a six months shut-down for the installation of FINUDA, a magnetic detector dedicated to the study of hypernuclear Physics. FINUDA is the third experiment running, in sequence, at DAFNE and operates while keeping on place the other detector KLOE. During the shut-down both the Interaction Regions have been equipped with remotely controlled rotating quadrupoles in order to operate at different solenoid fields. Among many other hardware upgrades one of the most significant is the reshaping of the wiggler pole profile to improve the field quality and the machine dynamic aperture. Commissioning of the collider in the new configuration has been completed in short time. The peak luminosity delivered to FINUDA has reached 6 1031 s-1 cm-2, with a daily integrated value exceeding 3 pb-1. Work presented by C. Milardi on behalf of the DAFNE Team
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THOBCH03	Barrier RF Systems in Synchrotrons	synchrotron, radiation, wakefield, beamloading	236
	C.M. Bhat Fermilab, Batavia, Illinois
	Recently, the barrier bucket techniques have been used in many interesting applications in proton synchrotrons around the world. Specially designed broad-band rf cavities are used to generate barrier buckets. At Fermilab we have barrier RF systems in four different rings and have used them for various beam gymnastics. Particularly, in the case of Fermilab Recycler Ring, all rf manipulations required during beam cooling, beam stacking and unstacking are carried out using barrier buckets. Also, we have explored new methods for increasing the beam intensities in the Main Injector. Here, I review various uses of barrier rf system in particle accelerators and possible new applications.
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THZCH01	Status of Tevatron Collider Run II and Novel Technologies for the Tevatron Luminosity Upgrades	synchrotron, radiation, wakefield, beamloading	239
	V.D. Shiltsev Fermilab, Batavia, Illinois
	In the Tevatron Run-II, 36 antiproton bunches collide with 36 proton bunches at the CDF and D0 interaction regions at 980 GeV per beam. We present current status and performance of the collider complex. The plan for Run-II luminosity upgrades will be presented and novel technologies for the upgrade will be discussed.
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THZCH02	Electron Cooling: Remembering and Reflecting	synchrotron, radiation, electron, wakefield	244
	I.N. Meshkov JINR, Dubna, Moscow Region
	The report contains a brief review of developments in electron cooling methods. The influence of electron cooling concepts on progress in particle beam physics is considered, particularly: development of alternative and complementary cooling methods - stochastic, laser, muon cooling; physics of cooled and intense particle beams; ordering effects in cooled ion beams and the idea of crystalline beams; intrabeam scattering in cooled beams, etc. Creation of new accelerator technology, based on electron cooling and its application to different fields of experimental physics, particle, nuclear and atomic physics, is described. Modern trends and new concepts of electron cooling applications are discussed.
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THZCH03	JACoW, a Collaboration Serving the Accelerator Community	synchrotron, radiation, electron, wakefield	249
	J. Poole, C. Petit-Jean-Genaz CERN, Geneva
	The Joint Accelerator Conferences Website started from an idea to publish the conference proceedings on the WWW and has grown to an international collaboration which does much more than just publish the proceedings and is currently supported by seven conference series. Through attendance at Steering Committee meetings and Team Meetings and through active participation in the work of the editorial teams of sister conferences, people with the responsibility for the production of the electronic versions of conference proceedings come together to learn from the experience of colleagues, and to develop common approaches to problems. The activities of the collaboration cover all aspects of electronic publication and have recently extended into conference scientific programme management. This paper reviews the history of the collaboration, describes some of the highlights in the activities during the life of the collaboration and presents the current status and future plans.
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THOALH01	Bunch Length Measurements at the SLS Linac using Electro-optical Techniques	laser, synchrotron, wakefield, electron	253
	A. Winter, M. Tonutti RWTH, Aachen S. Casalbuoni, P. Schmüser, S. Simrock, B. Steffen DESY, Hamburg T. Korhonen, T. Schilcher, V. Schlott, H. Sigg, D. Suetterlin PSI, Villigen
	The temporal profile of the electron bunches in the SLS Linac will be determined by means of electro-optical techniques. A mode locked Ti:Sa Laser with 15 fs pulse width is used for coincidence measurements between the laser pulse and the coherent transition radiation (CTR) generated by short electron bunches. Synchronization accuracy of 100 fs rms between the 3 GHz Linac RF and the 81 MHz repetition rate of the laser was achieved, which is important for the optimum time resolution of the applied electro-optical sampling technique. Likewise, a mode locked Nd:YAG laser with 400 ps long pulses will be used for electro-optical autocorrelation measurements between the CTR and the laser pulses. This alternative technique promises single shot capability and requires much relaxed synchronization stability between laser and electron beam.
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THOALH02	Development of the Non-invasive Beam-size Monitor using ODR	laser, wakefield, beamloading, beamlosses	256
	T. Muto, S. Araki, H. Hayano, V. Karataev, N. Terunuma, J. Urakawa KEK, Ibaraki R. Hamatsu TMU, Hatioji-shi,Tokyo A. Naumenko, A.P. Potylitsyn Tomsk Polytechnic University, Physical-Technical Department, Tomsk
	The beam-size monitor based on Optical Diffraction Radiation (ODR) has been developed at the KEK-ATF. Because of its non-invasive nature, the ODR monitor might be one candidate to measure the extreme-low emittance electron beam for future LC?s and x-ray free electron lasers. To evaluate the beam-size, the angular distribution of the ODR emitted by the beam when crossing a slit in a metallic foil was measured. In the first trial, we observed interference patterns between ODR and backgrounds which may be the synchrotron radiation from most nearest bending magnet at the ATF extracted line. By the installation of the ceramic mask in front of our target, this interference was vanished. And comparing with the result of ODR measurements, we installed the wire scanner in the same position of our monitor. In this paper, we will present developments of the ODR monitor with some experimental results.
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THOALH03	The Measurements of the Longitudinal Beam Profile on the Preinjector VEPP-5	laser, wakefield, beamloading, beamlosses	259
	S. Gurov, P.A. Bak, P.V. Logatchev, V. Pavlov, E. Pyata BINP SB RAS, Novosibirsk D. Chernousov ICKC, Novosibirsk
	For effective work of preinjector VEPP-5 it is necessary 3 ns bunch with charge 1* 1010 electrons from termogun compress to bunch with 40 ps duration on the positron target. A new streak-camera with RF cavity on the main linac frequency is used. Streak-camera with circle scanning allows see 350 ps single light signal with sub-ps resolution. An additional slow scanning can obtain the trochoidal scanning. Thus one can see with picosecond resolution and with less then 1 psec synchronization the train of ten bunches which are spacing by 350psec. The results of worked streak-camera with RF-cavity for circle scanning are presented.
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THYLH01	Beam Diagnostics at the VUV-FEL Facility	electron, radiation, undulator, wakefield	262
	J. Feldhaus, D. Noelle DESY, Hamburg
	The free electron laser (FEL) at the TESLA Test facility at DESY will be the first FEL user facility for VUV and soft X-ray radiation down to 6 nm wavelength, the commissioning starts in summer 2004. Commissioning as well as stable FEL operation require a combination of different diagnostic tools for measuring both electron and photon beam parameters, including the full phase space distribution of the bunch charge, exact timing with sub-picosecond resolution, electron and photon beam overlap along the undulator, radiation beam position in the user area 50-70 m behind the undulator, intensity and spectral distribution of the radiation pulses and others. Much effort has been put in the development of instrumentation for measuring the longitudinal bunch charge distribution, for controlling the electron beam orbit along the undulator, and for online monitoring the radiation intensity, position and spectral distribution. This contribution gives an overview of the complete electron and photon beam diagnostics of the FEL facility and focuses particularly on the instrumentation which is crucial or specific for the FEL operation.
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THOBLH01	Recent Improvement of Slow-extraction at HIMAC Synchrotron	electron, extraction, radiation, undulator	267
	T. Furukawa, T. Furukawa, T.H. Uesugi Chiba University, Graduate School of Science and Technology, Chiba T. Fujimoto, M. Kanazawa, K. Noda, S. Shibuya, E. Takada, S. Yamada NIRS, Chiba-shi T. Naruse Seikei University, Graduate School of Engineering, Tokyo
	At HIMAC synchrotron, two kinds of slow-extraction method have been developed and utilized: third-order resonant slow-extraction and that with RF-knockout, not only for ion therapy but also for physics and biological experiments. Thus, the improvements of the extracted beam quality have also been carried out in both methods. One of the improvements is the global spill control. The global spill is improved owing to analytical approach in both methods. Cooperating with the feedback system, the flat spill is easily obtained without gain control of the feedback during the extraction. On the other hand, the effect of longitudinal motion for the bunched beam was studied to suppress the frequency component of the synchrotron oscillation in the spill ripple. Further, the transport of the extracted beam is readjusted for controlling the beam size. In this paper, recent improvement of slow-extraction at HIMAC is presented.
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THOBLH02	Ultrafast Compton Scattering X-Ray Source Development at LLNL	extraction, radiation, undulator, wakefield	270
	F.V. Hartemann, S. Anderson, C.P.J. Barty, S.M. Betts, R. Booth, J. Brown, K. Crane, R.R. Cross, D.N. Fittinghoff, D. Gibson, E.P. Hartouni, J. Kuba, G.P. Le Sage, D.R. Slaughter, P.T. Springer, A. Tremaine, A.J. Wootton LLNL, Livermore, California J. Rosenzweig UCLA, Los Angeles, California
	The LLNL PLEIADES (Picosecond Laser-Electron Inter-Action for the Dynamical Evaluation of Structures) facility is now operating between 30 and 80 keV, and produces > 5 x 10⁶ photons per shot at 10 Hz. This important milestone offers a new opportunity to develop laser-driven, compact, tunable x-ray sources for critical applications such as NIF diagnostics, time-resolved material studies, and advanced biomedical imaging. Initial x-rays were captured with a CCD using a CsI scintillator; the photon energy was measured at approximately 70 keV, and the observed spectral and angular distributions found to agree very well with three-dimensional codes. The electron beam was focused to 30 um rms, at 54 MeV, with 250 pC of charge, a relative energy spread of 0.2%, and a normalized emittance of 10 mm.mrad. Optimization of the x-ray dose is currently underway, with the goal of reaching 10⁷ photons per shot and a peak brightness approaching 10¹⁷ photons/mm2/mrad2/s/0.1%bandwidth. High-Z K-edge radiographs have been demonstrated, as well as diffraction using highly-ordered pyrolytic graphite crystals. Nonlinear scattering experiments, using a tightly focused laser spot will also be discussed, as well as plans to develop a source capable of reaching 1% conversion efficiency from the electron beam kinetic energy into x-rays, and ultrafast diffraction experiments.
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THOBLH03	BESSY II Operated as a Primary Source Standard	extraction, undulator, wakefield, laser	273
	R. Klein, R. Thornagel, G. Ulm PTB, Berlin
	The Physikalisch-Technische Bundesanstalt (PTB) is the German National Metrology Institute and responsible for the realization and dissemination of the legal units in Germany. For the realization of the radiometric units in the VUV and X-ray spectral range PTB has been using calculable synchrotron radiation of bending magnets from the BESSY I and BESSY II electron storage rings for more than 20 years. The spectral photon flux of synchrotron radiation can be precisely calculated by Schwinger's theory. Therefore, all the storage ring parameters entering the Schwinger equation have to be measured with low uncertainty which requires a stable and reproducible operation of the storage ring. At BESSY II, PTB has installed all equipment necessary to measure the electron energy, the electron beam current, the effective vertical source size and the magnet induction at the radiation source point as well as all geometrical quantities with low uncertainty. The measurement accuracy for these quantities enables PTB to calculate the spectral photon flux from the visible up to the soft X-ray range with relative uncertainties below 0.4 %. We report on the measurement of the storage ring parameters with low uncertainty.
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THPKF001	Status of 3 GeV CANDLE Synchrotron Light Facility Project	extraction, undulator, wakefield, laser	2251
	V.M. Tsakanov, M. Aghasyan, G. Amatuni, V.S. Avagyan, A. Grigoryan, B. Grigoryan, M. Ivanyan, V. Jalalyan, D. Kalantaryan, V.G. Khachatryan, E.M. Laziev, Y.L. Martirosyan, R.H. Mikaelyan, S. Minasyan, K.N. Sanosyan, S. Tatikian, S. Tunyan, A. Vardanyan CANDLE, Yerevan
	CANDLE- Center for the Advancement of Natural Discoveries using Light Emission – is a 3 GeV third generation synchrotron light facility project in Republic of Armenia. The presentation includes the main considerations that underlie the Conceptual Design Report of the project and the progress made after the last EPAC conference. An overview of machine and beam physics study, the prototype and laboratory development is given.

THPKF002	Linac RF Control System for CANDLE. Design and Simulation	extraction, undulator, linac, wakefield	2254
	A. Vardanyan, G. Amatuni CANDLE, Yerevan
	The design and constructional features of the control system for 500 MHz and 3 GHz RF system of CANDLE linac are presented. The linac includes an electron gun that is modulated by 500 MHz generator to produce 1 ns electron bunches, 500 MHz and 3 GHz bunchers, pre-accelerating cavity and the main accelerating section at 3 GHz. An important feature of the presented control system is a high level synchronization of amplitude-phase characteristics of the sub-systems that provide the required energy-space characteristics of the accelerated beam. This puts strict requirements on RF frequency, amplitude and phase stabilization. A digital feedback system has been adopted to provide flexibility in the control algorithms. The main feature is a 9 MHz sampling rate for the cavity signals and digital I/Q detection. The design was performed using the RF analyze tool, based on MATLAB SIMULINK, which allows the simulation and analyzes of the field regulation quality. The simulation results for CANDLE Linac RF system, based on the output parameters of electron beam are given.

THPKF004	The Australian Synchrotron Project - Update	extraction, undulator, linac, wakefield	2257
	A. Jackson ASP, Melbourne
	The Australian Synchrotron - a 3rd generation synchrotron light facility based on a 3-GeV electron storage ring - is under construction at a site adjacent to Monash University in the Metropolitan District of Melbourne. Site preparation started in September 2003 and project completion is scheduled for March 2007. In this paper we present an overview of the facility and discuss progress to date in meeting this very agressive schedule.

THPKF005	The Australian Synchrotron Project Storage Ring and Injection System Overview	extraction, undulator, linac, wakefield	2260
	G. LeBlanc, M.J. Boland, Y.E. Tan ASP, Melbourne
	This paper describes the Australian Synchrotron storage ring. The storage ring is a 3 GeV machine with 14 cells and a circumference of 216 m. The unit cell is based on a Double Bend Achromat (DBA) structure. The design of the magnet lattice and the results of simulations pertaining to the storage ring performance are presented.

THPKF006	Lifetime Studies in the LNLS Electron Storage Ring	extraction, undulator, linac, wakefield	2263
	N.P. Abreu, N.P. Abreu UNICAMP, Campinas, São Paulo P.F. Tavares LNLS, Campinas
	In this paper we present a set of measurements performed at the 1.37 GeV electron storage ring of the Brazilian Synchrotron Light Source. We measured the beam lifetime as a function of: current per bunch, gap voltage and position of horizontal and vertical scrapers. Those measurements helped us to determine the contribution of various particle loss mechanisms (Touschek, elastic and inelastic scattering and quantum fluctuations) to the lifetime of the beam. Comparison with theory is also presented as well as an interpretation of each effect.

THPKF008	Injection System for the Canadian Light Source	extraction, undulator, wakefield, laser	2269
	R.M. Silzer, R. Berg, J.C. Bergstrom, L. Dallin, X. Shen, J.M. Vogt CLS, Saskatoon, Saskatchewan
	The full energy injection system for the Canadian Light Source is made up of a 250 MeV linac, a low energy transfer line, a 2.9 GeV booster synchrotron and a high energy transfer line. The system has routinely provided up to 25 mA peak current in a 132 ns pulse train to the CLS storage ring injection point since September 2003. By January, 2004, injection efficiencies up to 10% have been acheived and stored currents up to 25 mA were accumulated in less than 4 minutes. The injection timing system allows a variety of fill patterns. By July, 2004, injection rates of up to 2 mA per second should be possible providing a fill time of under one minute for a 100 mA stored beam.

THPKF009	Orbit Control for the Canadian Light Source	extraction, undulator, wakefield, laser	2272
	R. Berg, L. Dallin, J.M. Vogt CLS, Saskatoon, Saskatchewan
	The orbit control system for the Canadian Light Source storage ring is design to provide both static global orbit correction and active correction up to 100 Hz. The system is made up of 48 button monitors (X and Y), 24 fast correcter magnets (X and Y), and 24 slow correction coils in sextupole magnets (X and Y). To date the system has been use to apply static corrections the to CLS storage ring. While some works remains on the horizontal correction, the vertical orbit has been corrected to an RMS value of less tha 0.75 mm. Future corrections may be augmented by some beam-based magnet re-alignment. The orbit correction system is run on a MATLAB(R) operating system. Singular value decompostion (svd) was used extensively to reduce initial gross mis-alignments.

THPKF011	Vibration Measurements at the Swiss Light Source (SLS)	extraction, undulator, wakefield, laser	2275
	S. Redaelli, R.W. Assmann, W. Coosemans CERN, Geneva M. Böge, M. Dehler, L. Rivkin PSI, Villigen
	Vibration measurements have been carried out at the Swiss Light Source (SLS) site as part of a collaboration between the Paul Scherrer Institute (PSI) and the European Organization for Nuclear Research (CERN). The vibration level of the SLS floor and of some lattice elements of the SLS ring have been monitored under various experimental conditions. In particular, vibration spectra of lattice quadrupoles have been measured with a circulating beam and compared with the spectra of transverse beam positions, as measured with beam position monitors. This paper summarizes the results.

THPKF012	Operation of the Swiss Light Source: Top-up for Highest Performance	extraction, undulator, wakefield, laser	2278
	A. Lüdeke PSI, Villigen
	The Swiss Light Source (SLS) is now in its third year of user operation. Right from the beginning Top-up has been the standard mode of operation. Operation at a fixed beam current makes many applications easier to implement and allows to push several systems to higher performance. It enabled us to reach an excellent orbit stability and reproducibility and it made our users less sensitive to shortened beam lifetimes. We succeeded to satisfy the high demands on the availability of the injector system and our flexible timing system allows for a parallel usage of the Linac for experiments during Top-up operation. The impact of Top-up operation on the overall performance of the SLS is documented in this paper.

THPKF013	Terahertz Diagnostics for the Femtosecond X-ray Source at BESSY	undulator, wakefield, beamloading, lattice	2281
	K. Holldack, S. Khan, R. Mitzner, T. Quast, G. Wustefeld BESSY GmbH, Berlin
	A longitudinal electron density modulation caused by femtoslicing in a storage ring is accompanied by a strong broad band coherent THz-light emission between 0.3 and 10 THz at certain synchrotron radiation emitting devices downstream of the interaction region. A technique to use the THz signal for the control of the overlap of laser and electron bunch using fast infrared bolometers is described. A new dedicated THz extraction port at a bending magnet as well as a spectroscopic setup based on a Martin Puplett spectrometer will be commissioned in May 2004 together with the new femtoslicing source at BESSY. * A. Zholentz, M. Zoloterev, PRL 76/1996, 912** H.-J. Baecker et al., these proceedings

THPKF014	Status of the BESSY II Femtosecond X-ray Source	wakefield, beamloading, lattice, beamlosses	2284
	S. Khan, H.-J. Baecker, J. Bahrdt, H.A. Duerr, V. Duerr, W. Eberhardt, A. Gaupp, K. Godehusen, K. Holldack, E. Jaeschke, T. Kachel, D. Krämer, R. Mitzner, M. Neeb, W.B. Peatman, T. Quast, G. Reichardt, M.-M. Richter, M. Scheer, O. Schwarzkopf, F. Senf, G. Wustefeld BESSY GmbH, Berlin I. Hertel, F. Noack, W. Sandner, I. Will, N. Zhavarnokov MBI, Berlin
	At the BESSY II storage ring, work is in progress to produce X-ray pulses with 50 fs (fwhm) duration and tunable energy and polarization by "femtoslicing" [].This work includes extensive alterations to the storage ring (one new and one modified undulator, both in the same straight section, three additional dipole magnets, a new IR beamline, and nine meters of new vacuum vessels) and to two beamlines (relocation and new optical designs), as well as the installation of a femtosecond Ti:sapphire laser system. Commissioning is planned for May 2004. This paper reviews the principles and technical implementation of the new femtosecond X-ray source, and reports the status of the project. A. Zholentz, M. Zoloterev, Phys.Rev.Lett. 76 (1996), 912

THPKF015	Compressed Electron Bunches for THz-Generation - Operating BESSY II in a Dedicated Low Alpha Mode	wakefield, beamloading, lattice, beamlosses	2287
	G. Wustefeld, J. Feikes, K. Holldack, P. Kuske BESSY GmbH, Berlin
	For the first time an electron storage ring was operated during regular user shifts in a dedicated 'low alpha' mode, where electron bunches are compressed to 5 times shorter length for THz [] and short X-ray pulses experiments. The 1 mm rms-long bunches emit powerfull, coherent THz waves, up to 107 times stronger than incoherent radiation. We report on machine set up and operating experience. M. Abo-Bakr et al., Phys. Rev. Lett. 88, 254801 (2002)

THPKF018	Study for a Frequent Injection Mode at Delta with Beam Shutters Open	wakefield, synchrotron, beamloading, lattice	2296
	G. Schmidt, M. Benna, U. Berges, J. Friedl, A. Gasper, M. Grewe, P. Hartmann, R.G. Heine, H. Huck, D. Schirmer, S. Strecker, T. Weis, K. Wille, N. Zebralla DELTA, Dortmund
	The Dortmunder Electron Accelerator (DELTA) is a 1.5 GeV synchrotron light source. DELTA is now operated for 3000 h per year including 2000 h beam time for synchrotron radiation use. The maximum beam current is limited by rf power. To increase the average beam current a frequent injection scheme with beam shutters open is discussed for Delta. The peak current is not enlarged but the number of injections is increased to establish a quasi constant beam current. The quasi constant beam current has in addition the advantage of a constant synchrotron radiation heat-load on vacuum chambers and experiments. First tests at Delta have shown the gain in stability of the closed orbit during frequent injection. This article shows the possibility to install a frequent injection mode with beam shutters open during injection at DELTA. The results of measurements and simulations are presented.

THPKF019	PETRA III: A New High Brilliance Synchrotron Radiation Source at DESY	wakefield, synchrotron, emittance, beamloading	2299
	K. Balewski, W. Brefeld, W. Decking, Y.L. Li, G.K. Sahoo, R. Wanzenberg DESY, Hamburg
	DESY has decided to rebuild its 2304 m long accelerator PETRA II into a dedicated light source called PETRA III. The reconstruction is planned to start mid of 2007.The new light source will operate at an energy of 6 GeV, a current of 100 mA, a horizontal emittance of 1 nmrad and an emittance coupling of 1%. In the first phase thirteen insertion devices are foreseen. In this paper the principle layout of the machine will be presented. The structure of the new machine combines properties of conventional storage rings and light sources and is therefore quite unconventional. One of the major challenges of the project is to achieve the small emittances. The basic idea is to use so called damping wigglers with a total length of 80 m to reduce the horizontal emittance to the desired level. To obtain and maintain the small emittances imposes tight tolerances on spurious dispersion and orbit quality and stability. These limits will be given and discussed.

THPKF020	Improvements of the Orbit Stability at DORIS III	wakefield, emittance, beamloading, lattice	2302
	F. Brinker, O. Kaul DESY, Hamburg
	Running since 1974, the storage ring DORIS experienced a major modification in 1991 to run as a dedicated synchrotron radiation source since 1993. Since then the increasing requirements of the users on beam stability lead to a series of technical and operational measures to improve the beam conditions. The beam pipe has been mechanically isolated from the magnets, the cooling has been improved and this year a new orbit feedback came to operation which uses positron beam position monitors as well as photon monitors in the beam lines to stabilise the different photon beams. The different measures taken are presented.

THPKF021	Beam Current Limitations in the Synchrotron Light Source PETRA III	emittance, beamloading, lattice, beamlosses	2305
	R. Wanzenberg, K. Balewski DESY, Hamburg
	At DESY it is planned to rebuild the PETRA ring into a synchrotron radiation facility, called PETRA III, in 2007. Different operation modes with single bunch intensities of up-to 5 mA are been considered to serve the needs of the user communities. A first estimate of the impedance budget of PETRA III is given based on analytical models and numerical wakefield calculations of several vacuum chamber elements. The impedance model includes higher order modes (HOMs) of the cavities to cover also multi bunch aspects. The beam current limitations due to multi and single bunch instabilities are discussed. The build up of an electron cloud is also investigated for the option of using a positron beam to generate the synchrotron radiation.

THPKF022	Energy Calibration of the ANKA Storage Ring	emittance, beamloading, lattice, beamlosses	2308
	A.-S. Müller, I. Birkel, E. Huttel, M. Pont, F. Pérez, R. Rossmanith FZK-ISS-ANKA, Karlsruhe
	The ANKA electron storage ring operates in the energy range from 0.5 to 2.5 GeV. An energy calibration using the method of resonant spin depolarisation yields the exact beam energy of ANKA. In addition this method allows to determine other parameters such as nonlinear momentum compaction factor and incoherent synchrotron tune with extraordinary precision. This paper discusses experimental set-up and energy measurements. The reproducibility of the ANKA beam energy is addressed as well as energy drifts caused by thermal expansion of the floor.

THPKF046	Feasibility Study of Constant Current Operation at TLS Storage Ring	target, cathode, laser, beamloading	2377
	G.-H. Luo, H.-P. Chang, J. Chen, C.-C. Kuo, K.-B. Liu, R.J. Sheu, H.-J. Tsai, M.-H. Wang NSRRC, Hsinchu
	Several top-up experiments were carried out at various upgrade path of Taiwan Light Source. However, there were too many obstacles laid ahead of various stages to prevent the realization of top-up injection routinely. The small gap undulators, the requirement of small emittance operation and high current operation by SC cavity have promoted the top-up injection project to hightest priority. During last one and half years, a series of beam parameters measurement, subsystem checkout, installing various sensors, control program modification and hardware upgrade made the top-up injection more likely in routine operation. Discussions on the results of some measurements of booster and storage ring, the requirement of hardware upgrade and the future executable plan will be presented in this paper.

THPKF050	Electron Accelerator for Energy up to 5.0 MeV and Beam Power up to 50 KW with X-ray Converter	target, electron, cathode, laser	2380
	V. Auslender, A.A. Bryazgin, B.L. Faktorovich, E.N. Kokin, I. Makarov, S.A. Maximov, V.E. Nekhaev, A.D. Panfilov, V.M. Radchenko, M.A. Tiunov, V.O. Tkachenko, A.F.A. Tuvik, L.A. Voronin BINP SB RAS, Novosibirsk
	In recent time the new powerful industrial electron accelerators appear on market. It caused the increased interest to radiation technologies using high energy X-rays due to their high penetration ability. One of the promising directions is the creation of the irradiation installations for treatment of wide variety of food products. The report describes the industrial electron accelerator ILU-10 for electron energy up to 5 MeV and beam power up to 50 kW specially designed for use in industrial applications. The ILU-10 accelerator generates the vertical electron beam. The beam line turns the beam through an angle of 90 degrees and transports the beam to the vertically posed X-ray converter to generate the horizontal beam of X-rays. In the work presented results of measurements of the dose distribution profiles on the surface of treated products.

THPLT065	Study of Multiturn Injection at HIMAC Synchrotron	laser, vacuum, antiproton, 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.