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lattice

  
Paper Title Other Keywords Page
MOPCH078 Simulation of Dynamic Vacuum Induced Beam Loss ion, vacuum, beam-losses, target 211
 
  • C. Omet, P.J. Spiller, J. Stadlmann
    GSI, Darmstadt
  In synchrotrons, operated with intermediate charge state, heavy ion beams, intensity dependent beam losses have been observed. The origin of these losses is the change in charge state of the beam ions at collisions with residual gas atoms or molecules. The resulting A/Z deviation from the reference beam ion leads to modified trajectories in dispersive elements, which finally results in beam loss. At the impact positions, secondary particles are produced by ion stimulated desorption and increase the vacuum pressure locally. In turn, this pressure rise will enhance the charge change- and particle loss process and finally cause significant beam loss within a very short time (a few turns). A program package has been developed, which links the described beam loss mechanisms to the residual gas status and determines the vacuum dynamics. Core of the program is an ion optics tracking routine, in which the atomic physics and vacuum effects are embedded.  
 
MOPCH079 Ion Optical Design of the Heavy Ion Synchrotron SIS100 ion, extraction, synchrotron, acceleration 214
 
  • J. Stadlmann, K. Blasche, B. Franczak, C. Omet, N. Pyka, P.J. Spiller
    GSI, Darmstadt
  • A.D. Kovalenko
    JINR, Dubna, Moscow Region
  We present the ion optical design of SIS100, which is the main synchrotron of the FAIR project. The purpose of SIS100 is the acceleration of high intensity heavy ion and proton beams and the generation of short compressed single bunches for the production of secondary beams. Since ionization in the residual gas is the main loss mechanism, a new lattice design concept had to be developed, especially for the operation with intermediate charge state heavy ions. The lattice was optimized to generate a peaked loss distribution in charge separator like lattice cells. Thereby it enables the control of generated desorption gases in special catchers. For bunch compression, the lattice provides dispersion free straight sections and a low dispersion in the arcs. A special difficulty is the optical design for fast and slow extraction, and the emergency dumping of the high rigidity ions within the same short straight section.  
 
MOPCH089 Basic Aspects of the SIS100 Correction System Design dipole, quadrupole, resonance, sextupole 240
 
  • V.A. Mikhaylov, A.V. Alfeev, A.V. Butenko, A.V. Eliseev, H.G. Khodzhibagiyan, A.D. Kovalenko, O.S. Kozlov, V.V. Seleznev, A.Y. Starikov, V. Volkov
    JINR, Dubna, Moscow Region
  • E. Fischer, P.J. Spiller, J. Stadlmann
    GSI, Darmstadt
  The basic concept and the main design features of the superconducting SIS100 correction system are presented. The system comprises 84 steerer magnets consisting of two orthogonal dipole windings each for correction of the beam close orbit in vertical and horizontal planes, 48 normal sextupole windings connected in two families with opposite polarities for chromaticity correction and 12 units containing skew quadrupoles, normal and skew sextupoles and octupoles as well. The correction system should operate in a pulse mode corresponding to the accelerator cycle, i.e., up to 1 Hz. The main magnetic, geometrical and electrical parameters of the corrector magnets were specified. They are based on the beam dynamic analysis within the frames of the DF-type SIS100 lattice at different betatron tune numbers and tolerable alignment and manufacturing errors of the main lattice dipole and quadrupole magnets. The problem of reasonable unification of the corrector modules is discussed also, including their geometrical sizes, maximum supply current and cooling at 4.5 K. The concept of the SIS100 corrector magnets is based on the pulsed correctors designed for the Nuclotron.  
 
MOPCH096 LEIR Lattice injection, quadrupole, electron, optics 261
 
  • J. Pasternak, P. Beloshitsky, C. Carli, M. Chanel
    CERN, Geneva
  The Low Energy Ion Ring (LEIR) is a low energy ion cooling and accumulation ring and serves to compress long ion pulses from Linac 3 into high density bunches suitable for LHC ion operation. Issues of the LEIR lattice are to fulfil all constraints with a small number of quadrupoles and compensations of perturbations due to an electron cooler and gradients seen by the beam in the bending magnets during the ramp. Furthermore, experimental investigations via orbit reponse measurements will be reported.  
 
MOPCH137 An Anti-symmetric Lattice for High Intensity Rapid-cycling Synchrotrons injection, collimation, dipole, synchrotron 369
 
  • J. Wei, Y.Y. Lee, S. Tepikian
    BNL, Upton, Long Island, New York
  • S.X. Fang, Q. Qin, J. Tang, S. Wang
    IHEP Beijing, Beijing
  • S. Machida, C.R. Prior, G. Rees
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  Rapid cycling synchrotrons are used in many high power facilities like spallation neutron sources and proton drivers. In such accelerators, beam collimation plays a crucial role in reducing the uncontrolled beam loss. Furthermore, the injection and extraction section needs to reside in dispersion-free region to avoid couplings; a significant amount of drift space is needed to house the RF accelerating cavities; orbit, tune, and chromatic corrections are needed; long, uninterrupted straights are desired to ease injection tuning and to raise collimation efficiency. Finally, the machine circumference needs to be small to reduce construction costs. In this paper, we present a lattice designed to satisfy these needs. The lattice contains a drift created by a missing dipole near the peak dispersion to facilitate longitudinal collimation. The compact FODO arc allows easy orbit, tune, coupling, and chromatic correction. The doublet straight provides long uninterrupted straights. The four-fold lattice symmetry separates injection, extraction, and collimation to different straights. This lattice is chosen for the Beijing Spallation Neutron Source synchrotron.  
 
MOPCH141 Fast Argon-Baking Process for Mass Production of Niobium Superconducting RF Cavities ion, vacuum, superconductivity, superconducting-RF 381
 
  • B. Visentin, J.-P. Charrier, Y. Gasser, S. Regnaud
    CEA, Gif-sur-Yvette
  Baking is a necessary stage to reach high gradients with niobium superconducting cavities. In the standard process, so called "in-situ UHV baking", Nb cavity is baked at 110°C, during 2 days. During this treatment the inner part of the cavity is pumped out under Ultra High Vacuum conditions. In order to save time, "fast UHV baking" at 145 °C during 3 hours, under UHV pumping, has been successfully demonstrated* with similar improvements for cavity performances compare to the standard treatment. With the same simplification concern, we report here about an alternative method to avoid restrictive UHV requirements. Experiments have been carried out to perform "fast baking" in oxygen-free atmosphere, because bad performances have been observed with "fast baking" in air. These degradations are closely connected with a strong oxygen penetration in bulk analysed by Secondary Ion Mass Spectroscopyon on Nb samples .

*Proceedings of SRF Workshop – Ithaca (July 2005) – TuP05.

 
 
MOPCH167 PBG Superconducting Resonant Structures pick-up, radiation, cryogenics, simulation 454
 
  • M.R. Masullo
    INFN-Napoli, Napoli
  • A. Andreone, E. Di Gennaro, F. Francomacaro, G. Lamura
    Naples University Federico II, Napoli
  • V. Palmieri, D. Tonini
    INFN/LNL, Legnaro, Padova
  • M. Panniello, V.G. Vaccaro
    Naples University Federico II and INFN, Napoli
  We have realized normal conducting and superconducting “open resonators” based on the Photonic Band Gap (PBG) concept. We present the study, the optimisation and the measurements (from room temperature to 1.5 K) of Copper and Niobium PBG accelerating cavities operating at two different frequencies, 6 GHz and 16 GHz. All the structures are realised by extruding a single bulk piece of material, using a new machining method that minimizes the surface losses caused by the contact between different conducting parts. Measurements on the compact (54 mm external diameter) 16 GHz Nb structure are very good, showing in the superconducting state a quality factor Q =1.2x105 at the lowest temperature (1.5 K), limited by radiation losses only. The shunt impedance measured for the 16 GHz prototype is 70 MOhm/m, underlining the applicability of such resonant structures as accelerating cavities.  
 
MOPLS018 High-order Effects and Modeling of the Tevatron COSY, collider, damping, simulation 577
 
  • P. Snopok, M. Berz
    MSU, East Lansing, Michigan
  • C. Johnstone
    Fermilab, Batavia, Illinois
  The role and degree of nonlinear contributions to machine performance is a controversial topic in current collider operations and in the design of future colliders. A high-order model has been developed of the Tevatron in COSY, which includes the strongest sources of nonlinearities. Signatures of nonlinear behavior are studied and compared with performance data. The observed nonlinear effects are compared before and after implemention of nonlinear correction schemes.  
 
MOPLS026 Monitoring of Interaction-point Parameters using the 3-dimensional Luminosity Distribution Measured at PEP-II luminosity, monitoring, coupling, SLAC 598
 
  • B.F. Viaud
    Montreal University, Montreal, Quebec
  • W. Kozanecki
    CEA, Gif-sur-Yvette
  • C. O'Grady, J.M. Thompson, M. Weaver
    SLAC, Menlo Park, California
  The 3-D luminosity distribution at the IP of the SLAC B-Factory is monitored using e+ e- -> e+ e-, mu+ mu- events reconstructed online in the BaBar detector. The transverse centroid and spatial orientation of the luminosity ellipsoid provide a reliable monitor of IP orbit drifts. The longitudinal centroid is sensitive to small variations in the average relative RF phase of the beams and provides a detailed measurement of the phase transient along the bunch train. Relative variations in horizontal luminous size are detectable at the micron level. The longitudinal luminosity distribution depends on the e± overlap bunch length and the vertical IP beta-function beta*y. In addition to continuous online monitoring of all the IP parameters above, we performed detailed studies of their variation along the bunch train to investigate a temporary luminosity degradation. We also used controlled variations in RF voltage and beam current to extract separate measurements of the e+ and e- bunch lengths. The time-history of the beta*y measurements, collected over a year of routine high-luminosity operation, are compared with HER & LER phase-advance data periodically recorded in single-bunch mode.  
 
MOPLS041 MAD-X/PTC Lattice Design for DAFNE at Frascati survey, collider, emittance, luminosity 631
 
  • F. Schmidt
    CERN, Geneva
  • E. Forest
    KEK, Ibaraki
  • C. Milardi
    INFN/LNF, Frascati (Roma)
  In absence of a program that takes as an input the desired or known location of the magnets in the tunnel, accelerator designers have been using MAD8/X that looks at a ring as a sequence of magnets without a connection to the tunnel. In many simple examples that is just fine, but once more complicated structures are treated one is bound to play tricks with MAD. Here PTC comes to the rescue. It is shown how pieces of this machine that exist in MAD-X format are used in PTC to create this double ring, as found in the tunnel, with a proper survey in the forward and backward direction. Special elements have been implemented in MAD-X to allow the full PTC description of the machine. It is discussed how this real PTC model differs from the 'fake' MAD-X model and how well PTC describes the real machine.  
 
MOPLS043 Studies of the Beam-beam Interaction at CESR electron, positron, optics, injection 637
 
  • J.A. Crittenden
    Cornell University, Department of Physics, Ithaca, New York
  • M.G. Billing
    CESR-LEPP, Ithaca, New York
  The Cornell Electron Storage Ring facility operates 2-GeV multi-bunch electron and positron beams in a single beam-pipe. Electrostatic separators are used to separate the two counter-rotating beams at the parasitic crossings. When the beam energy was lowered from 5 GeV in 2003, the strength of the beam-beam interaction became a more important factor in beam-current limitations, resulting in extensive experimental and calculational studies of their characteristics. The CESR lattice design procedure has been modified recently to account explicitly for their dynamic consequences. We describe our modelling of the beam-beam interaction, experimental validation techniques, and investigations into compensation strategies.  
 
MOPLS050 Combined Phase Space Characterization at the PEP-II IP using Single-beam and Luminous-region Measurements emittance, luminosity, coupling, simulation 655
 
  • A.J. Bevan
    Queen Mary University of London, London
  • Y. Cai, A.S. Fisher, C. O'Grady, J.M. Thompson, M. Weaver
    SLAC, Menlo Park, California
  • W. Kozanecki
    CEA, Gif-sur-Yvette
  • B.F. Viaud
    Montreal University, Montreal, Quebec
  We present a novel method to characterize the e ± phase space at the IP of the SLAC B-factory, that combines single-beam measurements with a detailed mapping of luminous-region observables. Transverse spot sizes are determined in the two rings with synchrotron-light monitors & extrapolated to the IP using measured lattice functions. The 3-D luminosity distribution, as well as the spatial dependence of the transverse-boost distribution of the colliding beams, are measured using e+ e- –> mu+ mu- events reconstructed in the BaBar tracking detectors; they provide information on the luminous spot size, the e- angular divergence & the vertical emittance. The specific luminosity, which is proportional to the inverse product of the overlap IP beam sizes, is continuously monitored using Bhabha-scattering events. The combination of these measurements provide constraints on the horizontal & vertical spot sizes, angular divergences, emittances & beta functions of both beams at the IP during routine high-luminosity operation. Preliminary results of this combined-spot size analysis are confronted with measurements of IP beta-functions & overlap IP beam sizes at low beam current.  
 
MOPLS074 Collimation Optimisation in the Beam Delivery System of the International Linear Collider collimation, betatron, linear-collider, collider 721
 
  • F. Jackson
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  The collimation systems of the International Linear Collider (ILC) beam delivery system (BDS) must perform efficient removal of halo particles which lie outside the acceptable ranges of energy and spatial spread. An optimisation strategy is developed to improve the performance of the BDS collimation system. Primary considerations are the phase relationships between collimation systems and the final focus, and the overall bandwidth of the system.  
 
MOPLS097 Progress on the CTF3 Test Beam Line CLIC, CTF3, quadrupole, extraction 783
 
  • D. Schulte, S. Doebert, G. Rumolo, I. Syratchev
    CERN, Geneva
  • D. Carrillo
    CIEMAT, Madrid
  In CLIC, the RF power to accelerate the main beam is produced by decelerating a drive beam. The test beamline (TBL) of the CLIC test facility (CTF3) is designed to study and validate the stability of the drive beam during deceleration. This is one of the R&D items required from the International Linear Collider Technical Review Committee to demonstrate feasibility of CLIC. It will produce 30 GHz rf power in the GW range and allow to benchmark computer codes used for the CLIC decelerator design. Different options of this experimental beam line are discussed.  
 
MOPLS099 A Study of Failure Modes in the ILC Main Linac quadrupole, linac, klystron, simulation 789
 
  • D. Schulte, P. Eliasson, A. Latina
    CERN, Geneva
  • Eckhard. Elsen, D. Kruecker, F. Poirier, N.J. Walker, G.X. Xia
    DESY, Hamburg
  Failures in the ILC can lead to beam loss or even damage the machine. Also failures that do not lead to beam loss can affect the luminosity performance, in particular since some time is required to recover from them. In the paper a number of different failures is being investigated and the impact on the machine performance is being studied.  
 
MOPLS120 Mitigation of Emittance Dilution due to Transverse Mode Coupling in the L-band Linacs of the ILC emittance, linac, simulation, coupling 843
 
  • R.M. Jones, R.M. Jones
    UMAN, Manchester
  • R.H. Miller
    SLAC, Menlo Park, California
  The main L-band linacs of the ILC accelerate 2820 bunches from a center of mass of 10 GeV to 500 GeV (and in the proposed later upgrade, to 1 TeV). The emittance of the vertical plane is approximately 400 times less than that of the horizontal plane. Provided the vertical and horizontal mode dipole frequencies are degenerate, then the motion in each plane is not coupled. However, in reality the degeneracy will more than likely be removed with the eigen modes lying in planes rotated from the x and y planes due to inevitable manufacturing errors introduced in fabricating 20,000 cavities. This gives rise to a transverse coupling in the horizontal-vertical motion and can readily lead to a dilution in the emittance in the vertical plane. We investigate means to ameliorate this emittance dilution by splitting the horizontal-vertical tune of the lattice.  
 
MOPLS137 Tracking Studies to Determine the Required Wiggler Aperture for the ILC Damping Rings wiggler, damping, positron, injection 879
 
  • I. Reichel
    LBNL, Berkeley, California
  • A. Wolski
    Liverpool University, Science Faculty, Liverpool
  The injection efficiency of an ILC damping ring is closely tied to its acceptance. To maximize both, one wants a physical aperture as large as possible in the wiggler magnets, as these are the limiting physical apertures in the ring. On the other hand, a small aperture in the wiggler magnets is needed to achieve the required field profile, a high magnetic field that is very linear over the whole physical aperture of the magnet. Tracking studies were done for all proposed ILC damping ring lattices to determine their required apertures. Although a half-aperture of 8 or 10 mm had been proposed, our studies showed that, for most lattices, a 16 mm half-aperture is required. (For some lattices a 12 mm half aperture might suffice.) We present here the results of our studies, which led to adopting a 16 mm half-aperture in the current ILC damping ring baseline design.  
 
MOPLS138 Space Charge and Equilibrium Emittances in Damping Rings emittance, space-charge, damping, radiation 882
 
  • M. Venturini
    LBNL, Berkeley, California
  • K. Oide
    KEK, Ibaraki
  • A. Wolski
    Liverpool University, Science Faculty, Liverpool
  The unusual combination of small beam size and long ring circumference may cause space charge to have noticeable effects on the beam dynamics of the ILC (International Linear Collider) damping rings. One possible consequence is a modification of the vertical equilibrium emittance resulting from a non-ideal lattice. One simple way to account for this effect is to model space charge in the linear approximation within the framework of Oide's envelope (or Chao's matrix) formalism, whis is commonly used to calculate equilibrium emittances in lepton storage rings. However, this model would likely overestimate the effect as a linear approximation for space charge is accurate only in a small neighborhood of a bunch center. For a more accurate modelling, we propose to make use of Sacherer's envelope equations consisting of a closed set of equations for the second moments of a beam distribution that account for the nonlinear dependence of the space-charge force. Here we will illustrate how Sacherer's equations can be combined with Oide's formalism and apply the result to the ILC damping rings.  
 
MOPLS139 Choosing a Baseline Configuration for the ILC Damping Rings damping, wiggler, kicker, dynamic-aperture 885
 
  • A. Wolski
    Liverpool University, Science Faculty, Liverpool
  • J. Gao
    IHEP Beijing, Beijing
  • S. Guiducci
    INFN/LNF, Frascati (Roma)
  The damping rings for the International Linear Collider must be capable of accepting large beams from the electron and positron sources, and producing highly damped beams meeting demanding stability specifications, at the machine repetition rate of 5 Hz. Between March and November 2005, a program of studies was undertaken by an international collaboration of 50 researchers to compare a number of configuration options, including ring circumferences between 3 and 17 km. Here, we outline the studies and discuss the principal considerations in the choices of the baseline and alternative damping ring configurations.  
 
MOPLS142 Optimization of CESR-c Superferric Wiggler for the International Linear Collider Damping Rings wiggler, damping, dynamic-aperture, TESLA 894
 
  • J.T. Urban, G. Dugan, M.A. Palmer
    Cornell University, Laboratory for Elementary-Particle Physics, Ithaca, New York
  We present the results of an optimization of the Cornell Electron Storage Ring (CESR) superferric wiggler for the International Linear Collider (ILC) damping ring. The superferric CESR wiggler has been shown to have excellent beam dynamics properties in the ILC damping ring. We reduced the physical size, and hence cost, of the CESR wiggler with minimal degradation of ILC damping ring beam dynamics. We will provide a description of the optimized superferric wiggler and show the performance of this wiggler in the ILC baseline damping ring.  
 
TUODFI02 DAFNE Experience with Negative Momentum Compaction electron, positron, luminosity, feedback 989
 
  • M. Zobov, D. Alesini, M.E. Biagini, A. Drago, A. Gallo, C. Milardi, P. Raimondi, B. Spataro, A. Stella
    INFN/LNF, Frascati (Roma)
  There are several potential advantages for a collider operation with a lattice having a negative momentum compaction factor (alfa): bunches can be shorter and have a more regular shape; longitudinal beam-beam effects and synchrobetatron resonances are predicted to be less dangerous; requirements on sextupole strengths can be relaxed because there is no head-tail instability with the negative chromaticity. Since the lattice of the Frascati e+e- Phi-factory DAFNE is flexible enough to provide collider operation with alfa < 0, we have exploited this possibility to study experimentally the beam dynamics. The negative momentum compaction lattices have been successfully implemented and stable 1 A currents have been stored in both the electron and positron rings without any problem for RF cavities and feedback systems operation. First collisions have been tested at low currents. In this paper we describe the experimental results and compare them with expectations and numerical simulations. Present limitations to DAFNE operation with alfa < 0 are also discussed.  
slides icon Transparencies
 
TUPCH063 Novel Method for Beam Dynamics using an Alpha Particle Source simulation, injection, betatron, closed-orbit 1157
 
  • A. Sato, M. Aoki, Y. Arimoto, I. Itahashi, Y. Kuno, T. Oki, M. Yoshida
    Osaka University, Osaka
  PRISM is a future muon source which would provide high intense, monochromatic and pure muon beams. In order to achieve such muon beams we use a technique called Phase Rotation using an FFAG ring (PRISM-FFAG). The PRISM-FFAG ring is now under construction in Osaka university. The Commissioning will start in JFY 2007. In order to investigate the dynamical performances of the FFAG before the actual commissioning, we propose a novel experimental method. The principle of the method and its application to PRISM-FFAG will be described in this paper.  
 
TUPLS005 Preliminary Study of Using "Pipetron"-type Magnets for a Pre-accelerator for the LHC Collider LHC, injection, dipole, SPS 1493
 
  • G. De Rijk, L. Rossi
    CERN, Geneva
  • H. Piekarz
    Fermilab, Batavia, Illinois
  One of the luminosity limitations of the LHC is the rather low injection energy (0.45 TeV) with respect to the collision energy (7 TeV). The magnetic multipoles in the main dipoles at low field and their dynamic behaviour are considered to limit the achievable bunch intensity and emittance. We report on a preliminary study to increase the injection energy to 1.5 TeV using a two beam pre-accelerator (LHCI) in the LHC tunnel. The LHCI is based on "Pipetron" magnets as originally proposed for the VLHC. The aim of the study is to assess the feasibility and to identify the critical processes or systems that need to be investigated and developed to render such a machine possible.  
 
TUPLS016 Characterization of Crystals for Steering of Protons through Channelling in Hadronic Accelerators proton, scattering, CERN, extraction 1523
 
  • V. Guidi, S. Baricordi, M. Fiorini, G. Martinelli, A. Mazzolari, E. Milan
    UNIFE, Ferrara
  • E. Boscolo Marchi, G. Della Mea, R. Milan, S. Todros, A. Vomiero
    INFN/LNL, Legnaro, Padova
  • A. Carnera, D. De Salvador, A. Sambo
    Univ. degli Studi di Padova, Padova
  • Y.A. Chesnokov
    IHEP Protvino, Protvino, Moscow Region
  • Yu.M. Ivanov
    PNPI, Gatchina, Leningrad District
  • W. Scandale
    CERN, Geneva
  Channeling of relativistic particles through a crystal may be useful for many applications in accelerators, and particularly for collimation in hadronic colliders. Efficiency proved to be dependent on the state of the crystal surface and hence on the method used for preparation. We investigated the morphology and structure of the surface of the samples that have been used in accelerators with high efficiency. We found that crystal fabrication by only mechanical methods (dicing, lapping, and others) leads to a superficial damaged layer, which is correlated to performance limitation in accelerators. A planar chemical etching was studied and applied in order to remove the superficial damaged layer. RBS analysis with low-energy protons highlighted better crystal perfection at surface, as a result of the etching. Finally, measurement with 70-GeV protons at IHEP demonstrated a superior performance of the chemically cleaned crystals with respect to conventional samples. A protocol for preparation and characterization of crystal for channelling has been developed, which may be of interest for reliable operation with crystals in accelerators.  
 
TUPLS021 First Observation of Proton Reflection from Bent Crystals proton, scattering, CERN, collimation 1535
 
  • W. Scandale
    CERN, Geneva
  • V.T. Baranov, V.N. Chepegin, Y.A. Chesnokov
    IHEP Protvino, Protvino, Moscow Region
  • Yu.A. Gavrikov, Yu.M. Ivanov, L. P. Lapina, A.A. Petrunin, A.I. Schetkovsky, V. Skorobogatov, A. V. Zhelamkov
    PNPI, Gatchina, Leningrad District
  • V. Guidi
    UNIFE, Ferrara
  • A. Vomiero
    INFN/LNL, Legnaro, Padova
  We recently suggested using short bent crystals as primary collimators in a two-stage cleaning system for hadron colliders, with the aim of providing larger impact parameters in the secondary bulk absorber, through coherent beam-halo deflection*. Tests with crystals a few mm long, performed with 70 GeV proton beams at IEHP in Protvino, showed a channeling efficiency exceeding 85%. We also observed disturbing phenomena such as dechanneling at large impact angle, insufficient bending induced by volume capture inside the crystal, multiple scattering of non-channeled protons and, for the first time, a proton flux reflected by the crystalline planes. Indeed, protons with a tangent path to the curved planes somewhere inside the crystal itself are deflected in the opposite direction with respect to the channeled particles, with an angle almost twice as large as the critical angle. This effect, up to now only predicted by computer simulations**, produces a flux of particles in the wrong direction with respect to the absorber, which may hamper the collimation efficiency if neglected.

*A. Afonin et al. PhysRevLett.87.094802(2001).**A. M. Taratin and S.A.Vorobiev, Phys.Lett. A119(1987)425.

 
 
TUPLS025 Racetrack Non-scaling FFAG for Muon Acceleration betatron, acceleration, focusing, linac 1544
 
  • D. Trbojevic
    BNL, Upton, Long Island, New York
  The non-scaling Fixed-Field Alternating Gradient (FFAG) machines have very strong focusing, large momentum acceptance, and small dispersion and betatron functions. This report is a study of using a compact non-scaling FFAG in combination with the superconducting linac to accelerate the muons. The drift space between two kinds of combined function magnets in the previous non-scaling FFAG is removed. The time of flight in the non-scaling FFAG has a parabolic dependence on momentum. The large energy acceptance of the machine requires matching between the linac and the non-scaling FFAG arcs for both the betatron and dispersion functions over the entire energy range.  
 
TUPLS027 A Non-scaling FFAG for Radioactive Beams Acceleration (RIA) acceleration, injection, extraction, RIA 1547
 
  • D. Trbojevic, T. Roser, A.G. Ruggiero
    BNL, Upton, Long Island, New York
  One of the most expensive components of proposals to accelerate heavy radioactive beams is the superconducting linac. This is an attempt to design a non-scaling Fixed-Field Alternating-Gradient (FFAG) lattice to allow acceleration of heavy radioactive beams in a short time period with an acceptance in momentum of ±50%. As it had been previously reported the non-scaling FFAG has very small orbit offsets, very strong focusing, and large momentum acceptance. The lattice with small combined function magnets would provide substantial savings in the cost of the RF.  
 
TUPLS029 Optical Scheme of an Electrostatic Storage Ring quadrupole, storage-ring, simulation, ion 1553
 
  • V. Aleksandrov, Yu. Kazarinov, V. Shevtsov
    JINR, Dubna, Moscow Region
  • R. Doerner, H. Schmidt-Boecking, K.E. Stiebing
    IKF, Frankfurt-am-Main
  • A. Schempp
    IAP, Frankfurt-am-Main
  We consider the optical scheme of an electrostatic storage ring for low energy heavy ions/molecules* with special requirements to type of optical functions. Results of calculation are presented.

*C. P. Welsch et al. Proc. of PAC’03, 12-16 May 2003, Portland, Oregon, USA, p.1622.

 
 
TUPLS070 Chromaticity Control in Linear-field Nonscaling FFAGs by Sextapoles quadrupole, focusing, betatron, LEFT 1657
 
  • S.R. Koscielniak
    TRIUMF, Vancouver
  Because of their high repetition rate and large apertures, FFAGs are proposed for high-current medical accelerators suitable for cancer therapy. The linear-field nonscaling FFAG is made from repeating cells containing D and F combined function magnets. The betatron tune profiles decrease with momentum; this leads to the crossing of resonances. We examine how sextapole magnets may be used to flatten the tune profile; in particular (i) whether it is better to place them at the D or F; (ii) what strength is required; and (iii) what is their effect on the closed orbits and path length? The orbit geometry is derived from a thin-element model and the tunes from power series in the quadrupole strength. Chromaticity is corrected by coupling focusing strength to dispersion, which is far stronger in the F element. The zeros of the orbit dispersion become the poles of the "sextapole strength to flatten the tune at some particular momentum". We demonstrate that a weak F sextapole can produce a substantial horizontal tune flattening, and has little impact on other optical properties. Contrarily, placing the sextapole at the D element may destroy the dynamic aperture and or vertical focusing.  
 
TUPLS071 Minimum Cost Lattices for Nonscaling FFAGs LEFT, closed-orbit, acceleration, quadrupole 1660
 
  • S.R. Koscielniak
    TRIUMF, Vancouver
  Previously, linear-field FFAG lattices for muon acceleration have been optimized under the condition of minimum path length variation. For non-relativistic particles, as are employed in the hadron therapy of cancer, that constraint is removed allowing a wider range of design choices. We adopt the thin-element kick model for a degenerate F0D0 cell composed of D and F combined function magnets. The dipole field components are parametrised in terms of the bending at the reference momentum and the reverse bend angle. The split between positive and negative bending sets the shape of the closed orbits. The cost function, based on stored magnetic energy, is explored in terms of the split. Two cost minima are found, one corresponding to minimum peak magnet field in the F element, and another to minimum radial aperture in the D element. Analytic formulae are given for the minimization conditions. The minimum field lattice is similar to existing designs based on minimizing the path length variation, but the minimum aperture lattice presents a new direction for future detailed design studies.  
 
TUPLS072 Nonscaling FFAG with Equal Longitudinal and Transverse Reference Momenta closed-orbit, radio-frequency, acceleration, controls 1663
 
  • S.R. Koscielniak
    TRIUMF, Vancouver
  An unusual feature of linear-field nonscaling FFAG designs is that the radio-frequency is not necessarily synchronous with the reference orbit and momentum chosen for the lattice design. This arises because optics design prefers the reference geometry to be composed of straight lines and arcs of circles - either at the mean momentum, or at high momentum to centre the orbit in the F element. The asynchronous acceleration proposed for rapid acceleration has strong requirements to set the longitudinal reference at 1/4 and 3/4 of the momentum range to minimize phase slip. The usual particle-tracking programs, such as MAD, though sophisticated in the transverse plane, are far cruder in their longitudinal working and do not allow for a longitudinal reference momentum and RF phase independent of the transverse values. In the context of a thin-element lattice model, we show how to make the transverse reference momentum and optic design coincident with the longitudinal reference by adjusting the ratio of positive and negative bending in the D and F elements, respectively, and retaining a lines and arcs composition for the reference orbit. This prepares the way for MAD tracking.  
 
TUPLS073 Formulae for Linear-field Non-scaling FFAG Accelerator Orbits betatron, proton, ion, resonance 1666
 
  • M.K. Craddock
    UBC & TRIUMF, Vancouver, British Columbia
  • S.R. Koscielniak
    TRIUMF, Vancouver
  Non-scaling FFAG accelerators using constant-gradient F and D magnets with their fields decreasing outwards can compact ion orbits for a wide range of momentum (e.g., 1:2) into a narrow radial range. Designs to accelerate protons, ions and muons are currently being studied for proton drivers, cancer therapy facilities and neutrino factories. In this paper, analytic formulae are reported for some basic orbit properties, helping to make clear their dependence on the various design parameters and momentum. For the designs tested so far the numerical results are in excellent agreement with those obtained using lattice codes.  
 
TUPLS115 Transverse Phase Space Painting for the CSNS Injection injection, emittance, space-charge, simulation 1774
 
  • J. Qiu, J. Tang, S. Wang
    IHEP Beijing, Beijing
  • J. Wei
    BNL, Upton, Long Island, New York
  The CSNS accelerators consist of an 80 MeV proton Linac, and a 1.6 GeV rapid cycling synchrotron (RCS). The ring accumulates 1.88*1013 protons via H－stripping injection in the phase CSNS-I. The injected beam is painted into the large transverse phase space to alleviate space-charge effects. The uniformity of beam emittance is important in reducing the tune shift/spread due to space charge effect. The paper introduces two parameters to evaluate the uniformity of a distribution. To satisfy the low-loss design criteria, extensive comparison of different painting scenarios has been carried out by using the simulation code ORBIT. This paper gives detailed studies on painting schemes and the dependence on the lattice tune, the injection peak current, and also chopping rate.  
 
TUPLS116 Extraction System Design for the CSNS/RCS kicker, extraction, septum, shielding 1777
 
  • J. Tang, Y. Chen, Y.L. Chi, Y.L. Jiang, W. Kang, J.B. Pang, Q. Qin, S. Wang, W. Wang
    IHEP Beijing, Beijing
  • J. Wei
    BNL, Upton, Long Island, New York
  The CSNS extraction system takes use one of the four dispersion-free straight sections. Five vertical kickers and one Lambertson septum magnet are used for the one-turn extraction. The rise time of less 250 ns and the total kicking angle of 20 mrad are required for the kickers that are grouped into two tanks. The design for the kicker magnets and the PFN is also given. To reduce the low beam loss in the extraction channels due to large halo emittance, large apertures are used for both the kickers and septum. Stray magnetic field inside and at the two ends of the circulating path of the Lambertson magnet and its effect to the beam has been studied.  
 
WEOFI03 Beam Dynamics Simulation in e- Rings in SRFF Regime CSR, simulation, vacuum, synchrotron 1908
 
  • L. Falbo
    INFN-Pisa, Pisa
  • D. Alesini
    INFN/LNF, Frascati (Roma)
  • M. Migliorati
    Rome University La Sapienza, Roma
  The concept of strong RF focusing has been recently proposed to obtain locally short bunches in electron/positron colliders, by modulating the longitudinal bunch dimensions along the rings. To study the single bunch dynamics, a macroparticle numerical code has been written which simulates the effects of the objects generating broad band impedance along the ring and the effects of the coherent synchrotron radiation in dipoles and wigglers. The obtained results are shown and discussed.  
slides icon Transparencies
 
WEPCH008 The Beta-beam Decay Ring Design injection, insertion, resonance, ion 1933
 
  • A. Chancé, J. Payet
    CEA, Gif-sur-Yvette
  The aim of the beta-beams is to produce highly energetic beams of pure electron neutrino and anti-neutrino, coming from beta radioactive decays of the 18Ne10+ and 6He2+, both at gamma = 100, directed towards experimental halls situated in the Frejus tunnel. The high intensity ion beams are stored in a ring until the ions decay. Consequently, all the injected particles will be lost anywhere in the ring, generating a high level of losses. The ring circumference has to be a multiple of the SPS circumference. The straight sections must be as long as possible in order to maximize the useful neutrino flux. The straight section length is chosen to be about 35% of the circumference length, which gives 1-km-long arcs. The bend field in the arcs is then reasonable. The arc has been chosen as a 2Pi phase advance insertion, which improves the optical properties (dynamic aperture and momentum acceptance) and allows the easy determination of the working point by the optics of the straight sections.  
 
WEPCH009 Loss Management in the Beta-beam Decay Ring dipole, ion, collimation, injection 1936
 
  • A. Chancé, J. Payet
    CEA, Gif-sur-Yvette
  The aim of the beta-beams is to produce pure electronic neutrino and anti-neutrino highly energetic beams, coming from beta radioactive disintegration of the 18Ne10+ and 6He2+, both at gamma = 100, directed towards experimental halls situated in the Frijus tunnel. The high intensity ion beams are stored in a ring, until the ions decay. Consequently, all the injected particles will be lost anywhere around the ring generating a high level of losses. In order to keep a constant neutrino flux, the losses due to the decay of the radioactive ions are compensated with regular injections. The new ion beam is then merged with the stored beam with a specific RF program Two sources of losses have been considered: -The beta-decay products: their magnetic rigidity being different from the reference one, they are bent differently and lost. -The losses during the injection merging process. The first one needs a particular ring design in order to insert appropriate beam stoppers at the right place. The second one needs a specific collimation system which allows beam longitudinal halo cleaning between two successive injections.  
 
WEPCH011 Optimisation of a New Lattice for the ESRF Storage Ring optics, resonance, quadrupole, ESRF 1942
 
  • A. Ropert, L. Farvacque
    ESRF, Grenoble
  The installation of canted undulators in some of the straight sections of the ESRF storage ring is envisaged in the future. In order to free maximum space in the straight sections and minimise the reduction in length of the undulators, a new lattice, in which the straight section quadrupole triplets are replaced by doublets, is being studied. The paper describes the main features of the lattice and presents the experimental results achieved so far.  
 
WEPCH018 Finite Elements Calculations of the Lattice and Ring Acceptance of the Heidelberg CSR CSR, quadrupole, ion, storage-ring 1960
 
  • H. Fadil, M. Grieser, A. Wolf, R. von Hahn
    MPI-K, Heidelberg
  A new Cryogenic Storage Ring (CSR) is currently being designed at MPI-K in Heidelberg. This electrostatic ring, which will store ions in the 20~300 keV energy range (E/Q), has a total circumference of 35.2 m and a straight section length of 2.8 m. The ring design was at first carried out with the optics code MAD in the first order approximation. Further investigation of the optics was performed with the finite elements electrostatic code TOSCA. The individual elements of the CSR (deflectors and quadrupoles) were calculated then a model of the entire ring was simulated with successful storage (tracking) of 20keV protons for many turns. The lattice parameters thus obtained were compared with the MAD results and show good agreement. The dynamic ring acceptance was also calculated for the standard operating point.  
 
WEPCH024 Matrix Formulation for Hamilton Perturbation Theory of Linearly Coupled Betatron Motion resonance, betatron, coupling, storage-ring 1975
 
  • M. Takao
    JASRI/SPring-8, Hyogo-ken
  Linear coupled motion in a circular accelerator was successfully parametrized through the transfer matrix approach, where normal mode Twiss and coupling parameters are defined as an extension of Courand and Snyder formulation. However it is not straightforward to assign analytical expressions to the coupling parameters. On the other hand the coupled motion was analytically solved by the Hamilton perturbation theory, which ingeniously describes the resonance phenomena. In the perturbation theory, however, the symplectic structure of the coupled motion is obscure in turn. Hence, for the purpose of combining both the theories with each other with keeping the respective virtues, we develop the matrix formulation based on the Hamilton perturbation theory. Since we have already known the solution of equation of motion, we can construct the transfer matrix in terms of the solution. Thus we formulate the betatron motion with linear coupling resonance in analytic and symplectic manner. As an application of the formulation, we investigate the two-dimensional beam ellipse in an electron storage ring.  
 
WEPCH028 Position Shuffling of the J-PARC Main Ring Magnets sextupole, quadrupole, resonance, betatron 1984
 
  • M. Tomizawa, K. Fan, S. Igarashi, K. Ishii, H. Kobayashi, A.Y. Molodozhentsev, K. Niki, E. Yanaoka
    KEK, Ibaraki
  • Y. Irie
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  • S. Machida
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  The J-PARC 50GeV main ring has 96 dipole, 216 quadrupole with 11 families and 72 sextupole magnets with 3 families. Magnets installation in the tunnel started last year and will be planed to finish by the end of next fiscal year. Field measurements of all magnets will soon finish by this March. Deviations for BL, B'L, B"L in dipole, quadrupole and sextupole magnets make COD, beta beat and third integer stopband, respectively. They can be reduced by choosing a pair of magnets with similar field deviation and by positioning them so as to cancel each other considering betatron phase (shuffling). In this paper, we will report our shufflling scheme chosen under the given schedule for installation and field measurements and also will show performances expected by the shufflings.  
 
WEPCH033 Single Particle Beam Dynamics Design of CSNS/RCS dipole, collimation, injection, extraction 1996
 
  • S. Wang, S.X. Fang, Q. Qin, J. Tang
    IHEP Beijing, Beijing
  • J. Wei
    BNL, Upton, Long Island, New York
  Rapid Cycling Synchrotron (RCS) is a key component of Beijing Spallation Neutron Source (BSNS). It accumulates and accelerates protons to design energy of 1.6 GeV and extracts high energy beam to the target. As a high beam density and high beam power machine, low beam loss is also a basic requirement. An optimal lattice design is essential for the cost and the future operation. The lattice design of BSNS is presented, and the related dynamics issues are discussed. The injection/extraction scheme and the beam collimation system design are introduced.  
 
WEPCH038 Nonlinear Characteristics of the TME Cell emittance, betatron, resonance, sextupole 2002
 
  • V.A. Kvardakov, E. Levichev
    BINP SB RAS, Novosibirsk
  The TME (Theoretical Minimum Emittance) cell is being used now for designing the lattice of different storage rings (SR sources, damping rings, FFAG accelerators, etc.). Strong sextupoles required to correct the natural chromaticity of the lattice reduce the dynamic aperture. In the paper we consider the main features of the nonlinear perturbation strength and its connection with the essential lattice parameters: horizontal emittance, betatron tunes, and natural chromaticity. The analytical results are compared with the computer simulation.  
 
WEPCH052 Injection System for Kharkov X-ray Source NESTOR injection, alignment, quadrupole, storage-ring 2038
 
  • A.Y. Zelinsky, P. Gladkikh, I.M. Karnaukhov, A. Mytsykov
    NSC/KIPT, Kharkov
  During the last three years a Kharkov X-ray generator NESTOR is under design and construction in NSC KIPT. According to the design report, electrons are injected in the storage ring at 100 MeV and ramped up to final energy 225 MeV. Due to compact design of the ring the injection trajectory of the beam will pass through fringe field of a NESTOR bending magnet. It brings additional difficulties on design of an injection channel. In the paper the layout, results of design and calculations of NESTOR injector channel are presented. The channel consists of two bending magnets, five-lens, asymmetrical, objective and two-lens matching cell to compensate dispersion and focusing effects of a dipole magnet fringe field and injection system elements (inflector). Presented results shows that designed lattice provides matching of injected beam parameters with the storage ring acceptance, is stable to element alignment errors and is easy controlled. The final values of the channel lens gradients can be defined only after measurements of inflector field profile.  
 
WEPCH057 Measurement and Optimization of the Lattice Functions in the Debuncher Ring at Fermilab optics, antiproton, kicker, injection 2050
 
  • V.P. Nagaslaev, K. Gollwitzer, V.A. Lebedev, A. Valishev
    Fermilab, Batavia, Illinois
  • V. Sajaev
    ANL, Argonne, Illinois
  A goal of the Tevatron Run-II upgrade requires substantial increase of antiproton production. The central step towards this goal is increasing the Debuncher ring admittance. Detailed understanding of the Debuncher's optics, aperture limitations and lattice functions is necessary. The method of the response matrix optimization has been used to determine quadrupole errors and corrections to the design functions. The measurement accuracy is about 5% due to the Beam Position Monitor system resolution and the small number of steering elements in the machine. We have used these accurate measurements to redesign the machine optics to maximize the acceptance of the Debuncher where the main limiting apertures are the stochastic cooling pickups and kickers. Accuracy of the measurements and the limitations are discussed as well as details of the optics modification.  
 
WEPCH058 Progress with Collision Optics of the Fermilab Tevatron Collider optics, quadrupole, luminosity, resonance 2053
 
  • A. Valishev, Y. Alexahin, G. Annala, V.A. Lebedev, V.P. Nagaslaev
    Fermilab, Batavia, Illinois
  • V. Sajaev
    ANL, Argonne, Illinois
  Recent advances in the measurement and modeling of the machine parameters and lattice functions at the Tevatron allowed modifications of the collision optics to be performed in order to increase the collider luminosity. As the result, beta functions in the two collision points were decreased from 35cm to 29cm which resulted in ~10% increase of the peak luminosity. In this report we describe the results of optics measurements and corrections. We also discuss planned improvements, including the new betatron tune working point and correction of the beta function chromaticity.  
 
WEPCH059 Linear Lattice Modeling of the Recycler Ring at Fermilab quadrupole, storage-ring, coupling, controls 2056
 
  • M. Xiao, V.P. Nagaslaev, A. Valishev
    Fermilab, Batavia, Illinois
  • V. Sajaev
    ANL, Argonne, Illinois
  The Recycler Ring at Fermilab is a fixed 8 GeV kinetic energy storage ring, by the use of permanent magnets in the ring lattice. It is a strong focusing FODO lattice made up of either two gradient magnets or two quadrupoles(in dispersion free straight sections). The magnetic properties of all magnets used were measured before installation and surveyed in place to minimize possible errors. Nevertheless, substantial differences are found in tunes and beta functions between the existing linear model and the real storage ring. It results in difficulties when tuning the machine to new lattice conditions. We are trying to correct the errors by matching the model into the real machine using Orbit Response Matrix(ORM) method. The challenge with ORM particular in this ring and the results are presented in this paper.  
 
WEPCH060 Linear and Nonlinear Coupling Using Decoupling Transformations coupling, storage-ring, quadrupole, sextupole 2059
 
  • A. Wolski, A. Sessler
    LBNL, Berkeley, California
  Linear coupling in a storage ring is conveniently analyzed in terms of transformations that put the single-turn map into block-diagonal form. Such a transformation allows us to define new variables, in which the dynamics are uncoupled. Thus, for example, the symplectic conditions are simply that the phase area in each of the uncoupled variables is preserved. In principle, a similar approach may be taken to nonlinear coupling; we discuss such an approach in this paper, giving some simple illustrations of the ideas, based on the well-known techniques of normal form analysis. We also discuss some obstacles to finding a nonlinear decoupling transformation in the general case.  
 
WEPCH062 Precision Measurement and Improvement of Optics for e+, e- Storage Rings optics, coupling, quadrupole, betatron 2065
 
  • Y.T. Yan, Y. Cai, W.S. Colocho, F.-J. Decker, J. Seeman, M.K. Sullivan, J.L. Turner, U. Wienands, M. Woodley, G. Yocky
    SLAC, Menlo Park, California
  Through horizontal and vertical excitations, we have been able to make a precision measurement of linear geometric optics parameters with a Model-Independent Analysis (MIA). We have also been able to build up a computer model that matches the real accelerator in linear geometric optics with an SVD-enhanced Least-square fitting process. Recently, with the addition of longitudinal excitation, we are able to build up a computer virtual machine that matches the real accelerators in linear optics including dispersion without additional fitting variables. With this optics-matched virtual machine, we are able to find solutions that make changes of many normal and skew quadrupoles for machine optics improvement. It has made major contributions to improve PEP-II optics and luminosity. Examples from application to PEP-II machines will be presented.  
 
WEPCH065 Lattices for High-power Proton Beam Acceleration and Secondary Beam Collection, Cooling, and Deceleration synchrotron, secondary-beams, proton, dipole 2074
 
  • S. Wang
    IHEP Beijing, Beijing
  • K.A. Brown, C.J. Gardner, Y.Y. Lee, D.I. Lowenstein, S. Peggs, N. Simos, J. Wei
    BNL, Upton, Long Island, New York
  Rapid-cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics b) long straight sections for low-loss injection, extraction, and high-efficiency collimation c) dispersion-free straights to avoid longitudinal-transverse coupling, and d) momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.  
 
WEPCH067 Implementation of TPSA in the Mathematica Code LieMath sextupole, COSY, octupole, linear-collider 2077
 
  • D. Kaltchev
    TRIUMF, Vancouver
  The Lie Algebra package LieMath written in the Mathematica language constructs the beamline map in a single-exponent Lie generator form. The algorithm (BCH-based map concatenation) has been recently enhanced with Truncated Power Series Algebra (TPSA) techniques.The polynomials produced by the series expansion of the Hamiltonian are replaced with arrays of coefficients (derivative structures) and the Poisson bracket and BCH are defined as operations on such structures. We have confirmed the statement that using automatic differentiation instead of symbolic operations increases the speed by least an order of magnitude. The code is equipped with a MAD parser and a normal form block allowing it to extract nonlinear chromaticity and amplitude detuning. The notebook was applied in FFAG studies and may be useful for the linear collider final focus or collimation systems.  
 
WEPCH072 The High Order Non-linear Beam Dynamics in High Energy Storage Ring of FAIR multipole, resonance, sextupole, octupole 2083
 
  • A.N. Chechenin, R. Maier, Y. Senichev, E. Senicheva
    FZJ, Jülich
  The High Energy Storage Ring (HESR) is part of the international project FAIR for antiproton physics with beam in the momentum range from 1.5 to 15 GeV/c to explore the research areas of hadron structure and quark-gluon dynamics. An important feature of the project is the combination of phase space cooled beams with thick internal targets. Therefore there are two obvious reasons of beam heating: the target-beam interaction and the intra-beam scattering. Another source of the beam size growth is the higher order resonances. In the paper we investigate the non-linear beam dynamics together with different correction schemes minimizing this effect and compare with other sources of beam heating. Since the tune working point has a spread dependent on the chromaticity correction scheme and space charge, we include in our consideration both effects as well. All beam dynamics calculations are carried out with the SIMBAD code from the Unified Accelerator Library (UAL). We use 10000 macro particles, grid sizes 64x64 and 1000 turns per run.  
 
WEPCH074 Progress with Non-linear Beam Dynamic Studies of the Diamond Storage Ring sextupole, injection, dynamic-aperture, DIAMOND 2089
 
  • R. Bartolini, I.P.S. Martin, B. Singh
    Diamond, Oxfordshire
  • J.K. Jones
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  The conflicting requirements of high-brightness photon beams combined with adequate beam lifetime and high injection efficiency mean careful control of the non-linear lattice is crucial to achieving optimum performance. As part of the optimisation of the Diamond storage ring, studies have been made of both the Touschek lifetime and storage ring injection process, with the help of on-momentum and off-momentum frequency maps. The effect of chromaticity on Touschek lifetime has also been investigated and several new sextupole settings were identified achieving good Touschek lifetime and injection efficiency.  
 
WEPCH075 Effect of Insertion Devices on Beam Dynamics of the Diamond Storage Ring Using Kick Maps injection, resonance, coupling, storage-ring 2092
 
  • B. Singh, A.I. Baldwin, R. Bartolini, I.P.S. Martin
    Diamond, Oxfordshire
  The effect of the all Phase-I Insertion Devices (IDs) on the beam dynamic of the Diamond storage ring has been investigated using the kick map modelisation of the IDs. Kick maps have been produced with high accuracy using the computer code RADIA, considering many longitudinal harmonics. The effect of IDs on the dynamic aperture, Touschek lifetime and injection efficiency in the low emittance lattice, was investigated considering both coupling errors and physical engineering apertures. Harmful resonances have been identified using Frequency Map Analysis (FMA) and full 6D tracking was performed to estimate the Touschek lifetime and the injection efficiency. Additionally, the kick maps have been used to generate feed-forward tables for compensation of linear optics distortion.  
 
WEPCH076 Renormalization Group Reduction of the Frobenius-Perron Operator resonance, betatron, sextupole, storage-ring 2095
 
  • S.I. Tzenov
    Universita' degli Studi di Salerno, Dipartimento di Fisica E.R. Caianiello, Baronissi
  The Renormalization Group (RG) method is adopted as a tool for a constructive analysis of the properties of the Frobenius-Perron Operator. The renormalization group reduction of a generic symplectic map in the case, where the unperturbed rotation frequency of the map is far from structural resonances driven by the kick perturbation has been performed in detail. It is further shown that if the unperturbed rotation frequency is close to a resonance, the reduced RG map of the Frobenius-Perron operator (or phase-space density propagator) is equivalent to a discrete Fokker-Planck equation for the renormalized distribution function. The RG method has been also applied to study the stochastic properties of the standard Chirikov-Taylor map.  
 
WEPCH077 Particle Tracking in a Sextupole Field using the Euler Method Approximation sextupole, dynamic-aperture, ELETTRA, LEFT 2098
 
  • S. Di Mitri, E. Karantzoulis
    ELETTRA, Basovizza, Trieste
  The purpose of this paper is to evaluate any differences in the single particle tracking through a magnetic lattice when sextupoles are treated either like sliced or single-kick elements. Only on-energy transverse motion is considered. Convergence and symplecticity of the method of sliced sextupoles are discussed. Dynamic apertures and transverse phase spaces applied to the Elettra synchrotron lattice are compared for the two cases.  
 
WEPCH085 Algorithms for Chromatic Sextupole Optimization and Dynamic Aperture Increase sextupole, dynamic-aperture, storage-ring, betatron 2116
 
  • E. Levichev, P.A. Piminov
    BINP SB RAS, Novosibirsk
  Strong chromatic sextupoles compensating natural chromaticity of a storage ring may reduce dynamic aperture drastically. In the case of several sextupole families, one can find a lot of ways to correct chromaticity, which provides different sizes of the dynamic aperture. Finding a solution that gives the largest dynamic aperture is an important task for the storage ring design and operation. The paper discusses several approaches to sextupole arrangement optimization in order to obtain a large dynamic aperture.  
 
WEPCH087 Normal Form for Beam Physics in Matrix Representation controls, coupling, CERN 2122
 
  • S.N. Andrianov
    St. Petersburg State University, Applied Mathematics & Control Processes Faculty, St. Petersburg
  • A.N. Chechenin
    FZJ, Jülich
  The modeling of long beam evolution dynamics in nonlinear accelerator structures has raised new interest in the effective methods of nonlinear effects calculation. Moreover, it is preferably to use both analytical tools and numerical methods for evolution modeling. Usually the standard numerical methods and computer codes are based on the concept of symplectic transfer maps, whereas the analytical tool is the theory of normal forms. The method of normal forms can be realized in symbolic and numerical modes easily enough. In this paper, we discuss the normal form theory based on the matrix formalism for Lie algebraic tools. This approach allows using well known methods of matrix algebra. This permits to compute necessary matrices step-by-step up to desired order of approximation. This procedure leads to more simple structure of matrix representation for very complicated structure of this map does not allow using this map for practical computing. Therefore, it is necessary to transform this map in more appropriate form. In another words the new matrix representation for the map is particularly simple and has explicit invariants and symmetries.  
 
WEPCH100 Application of the Lie-transform Perturbation Theory for the Turn-by-turn Data Analysis resonance, coupling, optics, betatron 2146
 
  • Y. Alexahin
    Fermilab, Batavia, Illinois
  Harmonic analysis of turn-by-turn BPM data is a rich source of information on linear and nonlinear optics in circular machines. In the present report the normal form approach first introduced by R. Bartolini and F. Schmidt is extended on the basis of the Lie-transform perturbation theory to provide direct relation between the sources of perturbation and observable spectra of betatron oscillations. The goal is to localize strong perturbing elements, find the resonance driving terms - both absolute value and phase - that are necessary for calculation of the required adjustments in correction magnet circuits: e.g. skew-quadrupoles for linear coupling correction. The theory is nonlinear and permits to analyze higher order effects, such as coupling contribution to beta-beating and nonlinear sum resonances.  
 
WEPCH102 Studies of the Nonlinear Dynamics Effects of APPLE-II Type EPUs at the ALS polarization, dynamic-aperture, multipole, simulation 2152
 
  • C. Steier, S. Marks, S. Prestemon, D. Robin, D. Schlueter, W. Wan, W. Wittmer
    LBNL, Berkeley, California
  Elliptically Polarizing Undulators (EPUs) have become more and more popular at synchrotron radiation sources, providing full polarization control of the photon beam. The fields of the most commonly used APPLE-II type EPUs have a very fast, intrinsic field roll-off, creating significant non-linearities of the beam motion with in some cases large impact on the dynamic (momentum) aperture. In general, the nonlinear effects get stronger with longer periods and higher undulator magnetic fields. One of the planned future beamlines at the ALS (MERLIN) will use a quasiperiodic EPU with 9 cm period and maximum B fields of about 1.3 T. We will present simulation studies for the proposed shimming schemes for this future device to reduce the nonlinear effects to acceptable values, as well as experimental studies for the existing 5 cm period EPUs already installed in the ALS.  
 
WEPCH130 Analysis of Symmetry in Accelerating Structures with Group Theory RF-structure, polarization, KEK 2227
 
  • S. Sakanaka
    KEK, Ibaraki
  Many rf cavities for modern accelerators have a variety of symmetry. There is a question as to what is the connection between the symmetry of a cavity and of its eigenmodes. This can be clarified* using the representation theory of groups. The geometric symmetry of a cavity can be expressed by a group of symmetry operations. The structure of this group can be represented by a set of matrices called representation. The group is associated with several irreducible representations which can express possible patterns of transformations under the symmetry operations. The irreducible representations are very suitable to express the symmetry of each eigenmode. This method can be used to improve the understanding of non-axially symmetric structures. In this paper, this method is first explained, and then, it is extended to the application of symmetric periodic structures.

*S. Sakanaka, Phys. Rev. ST Accel. Beams 8, 072002 (2005).

 
 
WEPCH145 Particle Tracking and Simulation on the .NET Framework simulation, KEK, controls, closed-orbit 2263
 
  • H. Nishimura, T. Scarvie
    LBNL, Berkeley, California
  Particle tracking and simulation studies are becoming complex. In addition to the sophisticated graphics, interactive scripting is becoming popular. A compatibility with the control system requires network and database capabilities. It is not a trivial task to fulfill various requirements without sacrificing the runtime performance. We evaluate the use of .NET to solve this issue by converting a C++ code Goemon* that is an object-oriented version of Tracy developed at ALS. The portability to other platforms will be mentioned in terms of Mono.

*H. Nishimura, PAC'01, Chicago, July 2001, p.3066.

 
 
WEPCH146 Intrabeam Scattering Studies for the ILC Damping Rings Using a New Matlab Code wiggler, damping, emittance, positron 2266
 
  • I. Reichel, A. Wolski
    LBNL, Berkeley, California
  A new code to calculate the effects of intrabeam scattering (IBS)has been developed in Matlab based on the approximation suggested by K. Bane*. It interfaces with the Accelerator Toolbox** but can also read in lattice functions from other codes. The code has been benchmarked against results from other codes for the ATF*** that use this approximation or do the calculation in a different way. The new code has been used to calculate the emittance growth due to intrabeam scattering for the lattices currently proposed for the ILC Damping Rings, as IBS is a concern, especially for the electron ring. A description of the code and its user interface, as well as results for the Damping Rings, will be presented.

*K. Bane, in Proceedings of EPAC2002, p.1443. **A. Terebilo, Accelerator Toolbox for MATLAB, SLAC-PUB-8732 and www-ssrl.slac.stanford.edu/at/. ***K. Kubo et al. PhysRevST AB.8.081001 (2005).

 
 
WEPCH150 The Accelerator Markup Language and the Universal Accelerator Parser quadrupole, multipole, collider, CERN 2278
 
  • D. Sagan, M. Forster
    Cornell University, Laboratory for Elementary-Particle Physics, Ithaca, New York
  • D.A. Bates, A. Wolski
    LBNL, Berkeley, California
  • T. Larrieu, Y. Roblin
    Jefferson Lab, Newport News, Virginia
  • T.A. Pelaia
    ORNL, Oak Ridge, Tennessee
  • S. Reiche
    UCLA, Los Angeles, California
  • F. Schmidt
    CERN, Geneva
  • P. Tenenbaum, M. Woodley
    SLAC, Menlo Park, California
  • N.J. Walker
    DESY, Hamburg
  A major obstacle to collaboration on accelerator projects has been the sharing of lattice description files between modeling codes. To address this problem, a lattice description format called Accelerator Markup Language (AML) has been created. AML is based upon the standard eXtensible Markup Language (XML) format; this provides the flexibility for AML to be easily extended to satisfy changing requirements. In conjunction with AML, a software library, called the Universal Accelerator Parser (UAP), is being developed to speed the integration of AML into any program. The UAP is structured to make it relatively straightforward (by giving appropriate specifications) to read and write lattice files in any format. This will allow programs that use the UAP code to read a variety of different file formats. Additionally this will greatly simplify conversion of files from one format to another. Currently, besides AML, the UAP supports the MAD lattice format.  
 
WEPCH161 The FFAG R&D and Medical Application Project RACCAM proton, acceleration, electron, synchrotron 2308
 
  • F. Meot
    CEA, Gif-sur-Yvette
  • B. Autin, J. Collot, J.F. Fourrier, E. Froidefond, F. Martinache
    LPSC, Grenoble
  • J.L. Lancelot, D. Neuveglise
    SIGMAPHI, Vannes
  The RACCAM project (Recherche en ACCelerateurs et Applications Medicales) has recently obtained fundings, extending over three years (2006-2008), from the French National Research Agency (ANR). RACCAM is a tripartite collaboration, involving (i) the CNRS Laboratory IN2P3/LPSC, (ii) the French magnet industrial SIGMAPHI, and (iii) the nuclear medecine Departement of Grenoble Hospital. The project concerns fixed field alternating gradient accelerator (FFAG) research on the one hand, and on the other hand their application as hadrontherapy and biology research machines. RACCAM's goal is three-fold, (i) participate to the on-going international collaborations in the field of FFAGs and recent concepts of "non-scaling" FFAGs, with frames for instance, the Neutrino Factory (NuFact) and the EMMA project of an electron model of a muon FFAG accelerator, (ii) design, build and experiment a prototype of an FFAG magnet proper to fulfil the requirements of rapid cycling acceleration, (iii) develop the concepts, and show the feasibility, of the application of such FFAG beams to hadrontherapy and to biology research.

*CEA/DAPNIA and IN2P3/LPSC **IN2P3/LPSC ***Grenoble University Hospital ****SIGMAPHI

 
 
WEPLS001 Secondary Particle Production and Capture for Muon Accelerator Applications target, proton, factory, simulation 2394
 
  • S.J. Brooks
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  Intense pulsed muon beams are required for projects such as the Neutrino Factory and Muon Collider. It is currently proposed to produce these from a high-Z target using a multi-megawatt proton driver. This paper examines the effect of proton energy on the yield and distribution of particles produced from tantalum and mercury, with further analysis using a tracking code to determine how these distributions will behave downstream, including a breakdown of loss mechanisms. Example 'muon front end' lattices are used from the UK Neutrino Factory design.  
 
WEPLS010 20 - 50 GeV Muon Storage Rings for a Neutrino Factory site, injection, sextupole, storage-ring 2415
 
  • G. Rees
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  • C. Johnstone
    Fermilab, Batavia, Illinois
  • F. Meot
    CEA, Gif-sur-Yvette
  Muon decay ring studies are being undertaken as part of the International Scoping Study (ISS) for a Neutrino Factory. A racetrack and an isosceles triangle shaped ring are under design, initially for a muon energy of 20 GeV, but with an upgrade potential for 50 GeV. Both rings are designed with long straights to optimize directional muon decay. The neutrinos from the muon decays pass to one or two distant detectors; the racetrack ring has one very long production straight, aligned with one detector, while the triangular ring has two straights, each half as long, which can be aligned with two detectors. Lattice studies, injection, collimation, and RF system design for the large acceptance, high intensity rings are discussed and the performance of the two rings compared.  
 
THPCH025 Electron Cloud Self-consistent Simulations for the SNS Ring electron, proton, SNS, simulation 2832
 
  • A.P. Shishlo, S.M. Cousineau, V.V. Danilov, S. Henderson, J.A. Holmes, M.A. Plum
    ORNL, Oak Ridge, Tennessee
  The electron cloud dynamics is simulated for the Spallation Neutron Source ring using the self-consistent electron-cloud model for long-bunched proton beams implemented in the ORBIT code. These simulations feature simultaneous calculations of the dynamics of the proton bunch and of the electron cloud, including electron multipacting using a realistic secondary emission surface model. The frequency spectra and growth rates of the proton bunch transverse instability are studied as functions of the RF cavity voltage. The effectiveness of an electron-cloud instability suppression system is also studied using an ORBIT model of the real feedback system. SNS is a collaboration of six US National Laboratories: Argonne National Laboratory (ANL), Brookhaven National Laboratory (BNL), Thomas Jefferson National Accelerator Facility (TJNAF), Los Alamos National Laboratory (LANL), Lawrence Berkeley National Laboratory (LBNL), and Oak Ridge National Laboratory (ORNL).  
 
THPCH028 Crystalline Beams at High Energies dipole, focusing, luminosity, quadrupole 2841
 
  • J. Wei
    BNL, Upton, Long Island, New York
  • S. Machida
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  • S. Ochi, H. Okamoto
    HU/AdSM, Higashi-Hiroshima
  • A. Sessler
    LBNL, Berkeley, California
  • Y. Yuri
    JAEA, Takasaki, Takasaki
  Previously it was shown that by crystallizing each of the two counter-circulating beams, a much larger beam-beam tune shift can be tolerated during the beam-beam collisions; thus a higher luminosity can be reached for colliding beams*. On the other hand, crystalline beams can only be formed at energies below the transition energy of the circular accelerators**. In this paper, we investigate the formation of crystals in two types of high-transition-energy lattices, one realized by three-cell missing dipole modules and the other with negative bends. The latter type satisfies the maintenance condition for a crystalline beam***.

*J. Wei and A.M. Sessler, “Colliding crystalline beams”, EPAC98, p. 862. **J. Wei et al. Physical Review Letters, 73 (1994) p. 3089.***J. Wei et al. Physical Review Letters, 80 (1998) p. 2606.

 
 
THPCH111 Digital Master Oscillator for the ISIS Synchrotron controls, simulation, synchrotron, target 3062
 
  • C.W. Appelbee, M.G. Glover
    CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
  Rutherford Appleton Laboratories in Oxfordshire is home to an 800MeV synchrotron particle accelerator called ISIS. Its main function is to direct a beam of protons into a heavy metal target to produce neutrons for scientists to analyse condensed matter. A second harmonic system is being developed to upgrade the beam current from 200uA to 300uA in order to drive a second target station. This is being achieved by the inclusion of four second harmonic cavities to increase the width of the RF bucket. In the past the six fundamental cavities were driven by an analogue master oscillator but the extra cavities will bring more difficultly in the phasing of the system. This could be more easily and precisely controlled by embedding a Direct Digital Synthesis core into an FPGA chip as the heart of a new digital Master Oscillator. This paper describes the initial research and feasibility of such a system for the setting up, phasing and synchronisation of the ten cavities in the ring. It also describes how more of the controls to the oscillator can be encompassed by digital means.  
 
THPLS004 Canadian Light Source Update coupling, undulator, emittance, electron 3269
 
  • L. O. Dallin, M.J. Sigrist, T. Summers
    CLS, Saskatoon, Saskatchewan
  The Canadian Light Source (CLS) storage ring has been operating routinely since commissioning was completed in the spring of 2004. Beam currents up to 230 mA have been achieved with the single superconducting RF cavity. With steady improvement beam lifetimes (1/e) of 10 hours at 170 mA and 0.25% coupling are now possible. In the last year the vertical tune was increased by 1 integer to produce a smaller vertical beam size in the ID straight sections. This year the horizontal tune will be increased to reduce the beam emittance. The vertical coupling has been reduced both globally and locally using a skew quadrupole response technique. A wide range of photons energies are provided by an initial complement of five insertion devices (IDs) and and two infrared (IR) ports. The 5 m straights have room for two IDs. The light cones from these IDs are separated by about 1.5 mrad by "chicaning" the electron beam in the straights. To date two IDs have been installed in one straight using the chicaning technique. As well, a superconducting wiggler and a in-vacuum undulator have been installed and commissioned. An AppleII type elliptically polarizing undulator will be installed in April 2006.  
 
THPLS030 Beam Optic Measurements for the Booster Synchrotron of the Diamond Light Source booster, injection, DIAMOND, quadrupole 3347
 
  • B. Singh, R. Bartolini, C. Christou, V.C. Kempson, I.P.S. Martin
    Diamond, Oxfordshire
  • J.K. Jones
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  The booster synchrotron of the Diamond Light Source is a full energy injector ramping from 100 MeV to 3 GeV with a repetition rate of 5 Hz. As part of the booster commissioning, beam optic measurements were performed to characterize the booster performance. Through the use of the beam position monitors, orbit corrections, tune and chromaticity measurements were performed at injection energy and during the ramp. A first comparison with the booster model is also discussed.  
 
THPLS032 ELETTRA New Full Energy Injector High Level Software controls, optics, ELETTRA, insertion-device 3353
 
  • C. Scafuri, F. Iazzourene
    ELETTRA, Basovizza, Trieste
  The control system for the new full energy injector* will be entirely based on Tango with an object oriented distributed architecture. The availability of the new and modern software platform led us to design and develop a new high level software framework which allows a model-based accelerator control. The new design is fully object oriented and follows a layered approach. The main layers provide a set of different views or abstractions of the underlying accelerator: field layer, machine layer, and optics layer. The field layer handles all the access and communications with the actual devices of the accelerator, e.g., power supplies, instrumentation, etc. The machine layer handles the machine layout description, functional constraints like the association of a string of magnets with one power supply, and the conversion from actual values acquired from the field into values meaningful to beam dynamics problems. The optics layer performs all the actual calculations concerning the beam like beta functions, damping times, etc. An important characteristic of the new library is the unified management of all the needed calibrations and configurations by means of a relational database.

*“Elettra New Full Energy Injector Status Report”, these proceedings.

 
 
THPLS043 Status of SESAME vacuum, dipole, power-supply, storage-ring 3383
 
  • G. Vignola, A. Amro, M. Attal, H. Azizi, A. Kaftoosian, F. Makahleh, M.M. Shehab, H. Tarawneh, S. Varnasseri
    SESAME, Amman
  An overview of the status of SESAME is presented. SESAME is a third generation light source facility, with an e-beam energy of 2.5 GeV, located in Allan, Jordan. The emittance is 26 nm.rad and 12 straights are available for insertion devices. The injector consists of a 22.5 MeV microtron and 800 MeV booster synchrotron, with a repetition rate of 1 Hz. The conceptual design of the accelerator complex has been frozen, and the engineering design is in progress. The phase I scientific program for SESAME has also been finalized, and it foresees 6 beam lines, including 2 IR ports. The construction of the SESAME building is in progress, and the beneficial occupancy is expected by the end of 2006. The completion of the accelerators complex construction is scheduled for the end of 2009.  
 
THPLS054 Closed Orbit Correction and Beam Dynamics Issues at ALBA quadrupole, multipole, dynamic-aperture, vacuum 3404
 
  • M. Muñoz, D. Einfeld, T.F. Günzel
    ALBA, Bellaterra
  ALBA is a 3 GeV light source being built in Spain. The light source should be operational in 2010.The lattice for the storage ring is now finalized. The basic cells is an extended DBA-like structure with finite dispersion in the straight sections, providing low emittance (under 5nmrad) , small beam cross sections at the source points (less than 150 micro-m horizontal and 10micro-m vertical), and a large number of straight sections (4 times 8m, 12 times 4.2m and 8 times 2.6m). In this paper we review the properties of the lattice with special emphasis in the closed orbit correction system and the lifetime limits.  
 
THPLS055 Effects of Phase 1 Insertion Devices at the ALBA Project undulator, resonance, wiggler, electron 3407
 
  • M. Belgroune, M. Muñoz
    CELLS, Bellaterra (Cerdanyola del Vallès)
  The ALBA new third generation light source offers a large number of straight sections to its community of users. Three types of straights will be available, 4 of 8 m, 12 of 4.2 m and 8 of 2.6 m. The compact lattice of a 268 m circumference ring is now mature and its main components are already fixed. We discuss here the beam dynamics studies performed for Phase 1 Insertion Devices (IDs) where two helical devices HU71, two in-vacuum undulators U21 and a multipole wiggler have been modeled using the kick map approach. This allowed defining the suitable compensation scheme in a machine where the vertical focusing is mainly controlled by the gradients in the dipole magnets. In addition, the Touschek lifetime computations and the identification of the limiting resonances using Frequency Map Analysis showed how strong the working point is in the presence of these IDs. Tolerances on the multipolar components due to the fields' roll-off have also been defined and allowed the progress in the IDs design.  
 
THPLS063 Nonlinear Beam Dynamics of TPS dynamic-aperture, sextupole, resonance, injection 3430
 
  • H.-P. Chang, P.J. Chou, C.-C. Kuo, G.-H. Luo, H.-J. Tsai, M.-H. Wang
    NSRRC, Hsinchu
  A design study of 3.0 GeV high performance low emittance storage ring Taiwan Photon Source has been conducted recently The natural emittance of the storage ring can be as low as 1.7 nm-rad in our design and its lattice structure is a 24-cell double bend achromat type with circumference of 518.4 m, which will be located in the existing NSRRC site in Hsinchu. The strong focusing requires strong aberration correction with nonlinear sextupole magnets. The distribution of the sextupoles and number of families are studied to ensure a good dynamic aperture. The nonlinear effects in both betatron and synchrotron motions are investigated. Nonlinear beam dynamics effects in the presence of magnetic field imperfections as well as the insertion devices are simulated. The physical aperture limitations are included in the study too, and the Touschek lifetime is calculated. The tracking data are analyzed using frequency map analysis method and corresponding beam dynamics behavior can be revealed more precisely.  
 
THPLS068 Design of Taiwan Future Synchrotron Light Source emittance, dynamic-aperture, coupling, synchrotron 3445
 
  • C.-C. Kuo, H.-P. Chang, C.-T. Chen, P.J. Chou, H.J. Jhao, G.-H. Luo, H.-J. Tsai, M.-H. Wang
    NSRRC, Hsinchu
  We report updated design works for a new 3-3.3 GeV synchrotron light source with a high performance and low emittance storage ring, called Taiwan Photon Source (TPS). With its natural horizontal emittance less than 2 nm-rad and low emittance coupling, TPS will be able to provide an extremely bright photon beam to the demanding users, especially the x-ray community. The lattice type of the TPS is a 24-cell DBA structure and the circumference is 518.4 m. We present the lattice design, the accelerator physics issues and its performances.  
 
THPLS073 Effect of Nonlinear Synchrotron Motion on TPS Energy Acceptance synchrotron, vacuum, emittance, sextupole 3451
 
  • M.-H. Wang, H.-P. Chang, C.-C. Kuo, G.-H. Luo
    NSRRC, Hsinchu
  For design of new generation synchrotron light source the first order momentum compaction factor is usually small. The contribution of second order momentum compaction factor can't be neglected. The longitudinal phase space changes significantly due to the nonlinear effect. This will affect the energy acceptance of the particles and reduce the Touschek beam life time. In this paper we analyze the effect of the nonlinear synchrotron motion of TPS lattice design*. The reduction of energy acceptance is estimated. The contribution to second order momentum compaction factor is discussed. Efforts to minimize this nonlinear effect will also be addressed.

*C. C. Kuo et al., "Design of Taiwan Future Synchrotron Light Source", these proceedings.

 
 
THPLS075 Progress in Development of Kharkov X-Ray Generator storage-ring, injection, quadrupole, electron 3457
 
  • A.Y. Zelinsky, V.P. Androsov, E.V. Bulyak, A. Dovbnya, I.V. Drebot, P. Gladkikh, V.A. Grevtsev, Yu.N. Grigor'ev, A. Gvozd, V.E. Ivashchenko, I.M. Karnaukhov, N. Kovalyova, V.P. Kozin, V. Lapshin, V.P. Lyashchenko, V. Markov, N.I. Mocheshnikov, V.B. Molodkin, A. Mytsykov, I.M. Necklyudov, F.A. Peev, O.V. Ryezayev, A.A. Shcherbakov, A. Shpak, V.L. Skirda, V.A. Skomorokhov, Y.N. Telegin, V.I. Trotsenko, O.D. Zvonarjova
    NSC/KIPT, Kharkov
  • A. Agafonov, A.N. Lebedev
    LPI, Moscow
  • J.I.M. Botman
    TUE, Eindhoven
  • R. Tatchyn
    SLAC, Menlo Park, California
  Over the past year the design, development and construction of NSC KIPT X-ray generator NESTOR has been in progress. NESTOR is a new type radiation source on the base of Compton scattering and a 40 - 225 MeV electron storage ring. Electrons are injected in the storage ring at 100 MeV and ramped up to final energy 225 MeV. It is supposed that stored electron beam current will be of about 200 mA. Along with use of Nd:Yag laser of 10 W average power which was developed by High-Q laser firm and optical resonator with accumulation gain of about 1000 it allows to provide X-ray radiation flux up to 1011 phot/s. NESTOR is the cooperative facility and is supported both as well Ukrainian government as NATO SfP project #977982. It is supposed that NESTOR will be in operation in the middle of 2007 year. The status of the project and main facility systems are described in the report.  
 
THPLS079 Bunch Diffusion Measurements at the Advanced Light Source photon, storage-ring, injection, electron 3466
 
  • F. Sannibale, W.E. Byrne, C.-W. Chiu, J. Guo
    LBNL, Berkeley, California
  • J.S. Hull, O.H.W. Siegmund, A.S. Tremsin, J. Vallerga
    UCB, Berkeley, California
  In storage ring based synchrotron light sources, a long beam lifetime is usually a fundamental requirement for a high integrated brightness. The dynamic aperture and the momentum acceptance of lattices are carefully studied and maximized as much as possible for a long lifetime performance. On the other hand, large momentum acceptance and dynamic aperture increase the probability that a particle diffuses from one bunch to another. Diffusion can represent a severe limitation for those experiments where the samples have long relaxation times requiring empty buckets between bunches. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory we have characterized the particle diffusion for the present lattice in order to evaluate its impact on a special user operation dedicated to these long relaxation time experiments and on the incoming top-off injection mode for the ALS.  
 
THPLS083 Implementation of the Double-waist Chicane Optics in SPEAR 3 optics, quadrupole, dipole, vacuum 3472
 
  • W.J. Corbett, M. Cornacchia, T. Dao, D. Dell'Orco, D. Harrington, R.O. Hettel, X. Huang, Y. Nosochkov, T. Rabedeau, F.S. Rafael, H. Rarback, A. Ringwall, J.A. Safranek, B. Scott, J.J. Sebek, J. Tanabe, A. Terebilo, C. Wermelskirchen, M. Widmeyer
    SLAC, Menlo Park, California
  • M. Yoon
    POSTECH, Pohang, Kyungbuk
  The SPEAR 3 upgrade produced two new 7.6 m racetrack straight sections in the 18 cell, 234 m magnet lattice. One of these straights houses four PEP-II style mode-damped RF cavities. The other straight will accommodate two new small-gap insertion devices separated by 10mrad in a magnetic chicane configuration. A quadrupole triplet has been installed at the midpoint of the chicane and the vertical tune has been raised by an integer to create a 'double waist' optics with betay = 1.6m in the center of each ID. Furthermore, as part of the optics upgrade, betay in the four straights adjacent to the racetrack sections was reduced from 5m to 2.5m. In this paper, we describe the physical implementation of the double-waist chicane optics and initial operational results.  
 
THPLS087 A Control Theory Approach for Dynamic Aperture dynamic-aperture, sextupole, controls, synchrotron 3478
 
  • J. Bengtsson
    BNL, Upton, Long Island, New York
  The dynamic aperture problem dates back to the design of the first synchrotrons. Over time, both analytical and numerical methods have been pursued. In the former case mainly by applying techniques developed for celestial mechanics to rather simplified equations of motion. Over the last decade, analysis of the Poincare map has become the method of choice. In particular, application of symplectic integrators, truncated power series algebra, and Lie series techniques has led to a complete set of tools for self-consistent numerical simulations and analytic treatment of realistic models. Nevertheless, a control theory for the general nonlinear case remains elusive. We summarize how to apply this framework to the design of modern synchrotron light sources. Moreover, we also outline how a control theory can be formulated based on the Lie generators for the nonlinear terms.  
 
THPLS088 Optimizing the Dynamic Aperture for Triple Bend Achromatic Lattices emittance, quadrupole, dipole, sextupole 3481
 
  • S.L. Kramer, J. Bengtsson
    BNL, Upton, Long Island, New York
  The Triple Bend Achromatic (TBA) lattice has the potential for lower natural emittance per period than the Double Bend Achromatic (DBA) lattice for high brightness light sources. However, the DBA has been chosen for 3rd generation light sources more often due to the higher number of undulator straight section available for a comparable emittance. The TBA has considerable flexibility in linear optics tuning while maintaining this emittance advantage. We have used the tune and chromaticity flexibility of a TBA lattice to minimize the lowest order nonlinearities using a high order achromatic tune condition, while maintaining a constant emittance. This frees the geometric sextupoles to counter the higher order nonlinearities. This procedure is being used to improve the nonlinear dynamics of the TBA as a proposed lattice for the NSLS-II facility. The flexibility of the TBA lattice will also provide for future upgrade capabilities of the beam parameters.  
 
THPLS089 Comparison of Double Bend and Triple Bend Achromatic Lattice Structures for NSLS-II emittance, sextupole, wiggler, dipole 3484
 
  • S.L. Kramer, J. Bengtsson, S. Krinsky
    BNL, Upton, Long Island, New York
  The Double Bend Achromatic (DBA) and the Triple Bend Achromatic (TBA) lattice have been studied rather extensively for use for the NSLS-II storage ring. The well known advantage of the TBA compared to the DBA is that the emittance per period has the potential to be considerably lower. However, the DBA has been chosen more often due to the greater number of ID straight sections for the users for a desired emittance. We present a comparison of these lattice structures based on the optimization of the non-linear driving terms from the chromatic sextupole and the ease of compensation of these terms using the higher order achromatic cancellation.  
 
THPLS090 Consideration of the Double Bend Achromatic Lattice for NSLS-II wiggler, emittance, insertion, dynamic-aperture 3487
 
  • S. Krinsky, J. Bengtsson, S.L. Kramer
    BNL, Upton, Long Island, New York
  We present the results of a study of the Double Bend Achromatic (DBA) lattice as a possible choice for the NSLS-II storage ring. The DBA possesses a large number of straight sections with easily tunable beta functions which can be used for insertion device sources and for damping wigglers to reduce emittance. The dispersive regions can be designed to minimize the strength of the chromatic correction sextupoles. A key constraint is the imposition of a limit on circumference which is closely tied to cost. We discuss optimization of the dynamic aperture by minimizing the non-linear driving terms using high-order achromatic cancellation in the non-linear lattice.  
 
THPLS091 Control of Dynamic Aperture with Insertion Devices optics, dynamic-aperture, quadrupole, sextupole 3490
 
  • T.V. Shaftan, J. Bengtsson, S.L. Kramer
    BNL, Upton, Long Island, New York
  It is well known that insertion devices (IDs) perturb the linear optics in the vertical plane. In particular, that the effect can be corrected locally by a symmetric arrangement of four quadrupoles on each side of the IDs. We show how to control an arbitrary set of IDs in this configuration with the response matrix for the beta-beat and perturbation of the phase advance and SVD, i.e., to maintain the dynamic aperture. We also evaluate the residual impact on the dynamic aperture from the nonlinear terms and outline how to control these. As an example, we discuss an impact of some ID models on the NSLS-2 dynamic aperture. Results for a single ID and a set of 20 IDs with random field strengths are presented.  
 
THPLS110 Injection Scheme for TPS Storage Ring injection, storage-ring, kicker, septum 3535
 
  • M.-H. Wang, H.-P. Chang, C.-C. Kuo, G.-H. Luo
    NSRRC, Hsinchu
  Taiwan Photon Source(TPS), a 3~3.3 GeV synchrotron light source with full energy injection is proposed to be built at NSRRC in Taiwan. In this paper we report the design of injection scheme for TPS. The space allocation of the injection components, the bumper design, the aperture consideration and the injection dynamics of injected and stored beam will all be discussed. The particle tracking of first few turns of injection is performed to evaluate the injection efficiency with the errors caused by the time jitter and amplitude stability of injection kickers. The issue of constant current operation will be also addressed.  
 
THPLS127 Plans for a 2nd Insertion Device in CAMD wiggler, multipole, TESLA, quadrupole 3583
 
  • V.P. Suller
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  • M.G. Fedurin, P. Jines, D.J. Launey, T.A. Miller, Y. Wang
    LSU/CAMD, Baton Rouge, Louisiana
  To allow the possible installation of a 2nd Insertion Device in the CAMD Light Source the lattice optic needs to be changed. The present configuration has a small vertical beta function in the long straight containing the 7T wiggler. The new optic will give small vertical beta at two long straights which are diametrically opposite. Test results with the new optic are presented together with the measured beam parameters. These are used to predict the photon beam performance for several types of Insertion Device which could be installed.