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MOXACH01 Worldwide Perspectives in Accelerators and the Rôle of CERN collider, linear-collider, luminosity, factory 1
 
  • R. Aymar
    CERN, Geneva
  After an analysis of the most probable medium and long-term evolution of Particle Accelerators and their worldwide perspectives, the presentation focuses on the specific role of CERN. It emphasizes CERNs mandate as defined by its convention, which is not only to build and operate the laboratory as a centre of excellence but to organize and steer particle physics in Europe. It should be the place where a coherent strategy for the whole field of European Particle Physics is discussed and elaborated in the best interest of the whole community. CERN should act as the driving force in the centre of a network of multilateral collaborating institutes where each laboratory brings its own contribution towards a common goal in a coordinated way following its specific skills and resources. It should favour mutual exchanges and collaborations to enable developments covering the whole range of CERN's activities from pure physics to accelerator and detector R&D. This is a necessary condition not only to make the LHC a success as the highest priority during the next few years, but also for Europe to continue its leading role in the quest to push further the high energy frontier in the future. That will require even more challenging and more complex facilities which will only be possible if built as unique and complementary in world-wide collaborations.  
Video of talk
Transparencies
 
MOPLT005 An Improved Collimation System for the LHC collimation, impedance, insertion, beam-losses 536
 
  • R.W. Assmann, O. Aberle, A. Bertarelli, H.-H. Braun, M. Brugger, L. Bruno, O.S. Brüning, S. Calatroni, E. Chiaveri, B. Dehning, A. Ferrari, B. Goddard, E.B. Holzer, J.-B. Jeanneret, J.M. Jimenez, V. Kain, M. Lamont, M. Mayer, E. Métral, R. Perret, S. Redaelli, T. Risselada, G. Robert-Demolaize, S. Roesler, F. Ruggiero, R. Schmidt, D. Schulte, P. Sievers, V. Vlachoudis, L. Vos, G. Vossenberg, J. Wenninger
    CERN, Geneva
  • I.L. Ajguirei, I. Baishev, I.L. Kurochkin
    IHEP Protvino, Protvino, Moscow Region
  • D. Kaltchev
    TRIUMF, Vancouver
  • H. Tsutsui
    SHI, Tokyo
  The LHC design parameters extend the maximum stored beam energy 2-3 orders of magnitude beyond present experience. The handling of the high-intensity LHC beams in a super-conducting environment requires a high-robustness collimation system with unprecedented cleaning efficiency. For gap closures down to 2mm no beam instabilities may be induced from the collimator impedance. A difficult trade-off between collimator robustness, cleaning efficiency and collimator impedance is encountered. The conflicting LHC requirements are resolved with a phased approach, relying on low Z collimators for maximum robustness and hybrid metallic collimators for maximum performance. Efficiency is further enhanced with an additional cleaning close to the insertion triplets. The machine layouts have been adapted to the new requirements. The LHC collimation hardware is presently under design and has entered into the prototyping and early testing phase. Plans for collimator tests with beam are presented.  
 
MOPLT009 The Design of the New Fast Extraction Channel for LHC extraction, septum, kicker, emittance 548
 
  • J. Borburgh, B. Balhan, E.H.R. Gaxiola, B. Goddard, Y. Kadi, J.A. Uythoven
    CERN, Geneva
  The Large Hadron Collider (LHC) project requires the modification of the existing extraction channel in the long straight section 6 of the CERN Super Proton Synchrotron (SPS). The new extraction will be used to transfer protons at 450 Gev/c as well as ions via the 2.8 km long transfer line TI 2 to the clockwise ring of the LHC. As the resonant extraction to the present SPS west area will be stopped after 2004, the electrostatic septa will be replaced by new fast extraction kicker magnets. The girder for the existing DC septa will be modified to accommodate a new septum protection element. Other modifications concern the replacement of a machine quadrupole, a new scheme for the extraction bumpers, new instrumentation and interlocks. The requirements and the design of the new extraction channel will be described as well as the modifications which will mainly be carried out in the long SPS shutdown 2005.  
 
MOPLT010 Collimation of Heavy Ion Beams in LHC ion, collimation, heavy-ion, scattering 551
 
  • H.-H. Braun, R.W. Assmann, A. Ferrari, J.-B. Jeanneret, J.M. Jowett
    CERN, Geneva
  • I.A. Pshenichnov
    RAS/INR, Moscow
  The LHC collimation system is designed to cope with requirements of proton beams having 100 times higher beam power than the nominal LHC heavy ion beam. In spite of this, specific problems occur for ion collimation, due to different particle-collimator interaction mechanism for ions and protons. Ions are subject to hadronic fragmentation and electromagnetic dissociation, resulting in a non-negligible flux of secondary particles of small angle divergence and Z/A ratios slightly different from the primary beam. These particles are difficult to intercept by the collimation system and can produce significant heat-load in the superconducting magnets when they hit the magnet vacuum chamber. A computer program has been developed to obtain quantitative estimates of the magnitude and location of the particle losses. Hadronic fragmentation and electromagnetic dissociation of ions in the collimators were considered within the frameworks of abrasion-ablation and RELDIS models, respectively. Trajectories of the secondary particles in the ring magnet lattice and the distribution of intercept points of these trajectories with the vacuum chamber are computed. Results are given for the present collimation system design and potential improvements are discussed.  
 
MOPLT012 Collimation in the Transfer Lines to the LHC injection, collimation, simulation, emittance 554
 
  • H. Burkhardt, B. Goddard, Y. Kadi, V. Kain, W.J.M. Weterings
    CERN, Geneva
  The intensities foreseen for injection into the LHC are over an order of magnitude above the expected damage levels. The TI 2 and TI 8 transfer lines between the SPS and LHC are each about 2.5 km long and comprise many magnet families. Despite planned power supply surveillance and interlocks, failure modes exist which could result in uncontrolled beam loss and serious transfer line or LHC equipment damage. We describe the collimation system in the transfer lines that has been designed to provide passive protection against damage at injection. Results of simulations to develop a conceptual design are presented. The optical and physical installation constraints are described, and the resulting element locations and expected system performance presented, in terms of the phase space coverage, local element temperature rises and the characteristics of the beam transmitted into the LHC.  
 
MOPLT016 Upgrade and Tests of the SPS Fast Extraction Kicker System for LHC and CNGS extraction, kicker, simulation, diagnostics 566
 
  • E.H.R. Gaxiola, A. Antoine, P. Burkel, E. Carlier, F. Castronuovo, L. Ducimetière, Y. Sillanoli, M. Timmins, J.A. Uythoven
    CERN, Geneva
  A fast extraction kicker system has been installed in the SPS and successfully used in extraction tests in 2003. It will serve to send beam to the anticlockwise LHC ring and the CNGS neutrino facility. The magnets and pulse generators have been recuperated from an earlier installation and upgraded to fit the present application. Hardware improvements include diode stacks as replacement of the previous dump thyratron switches, a cooling system of the magnets, sensors for its ferrite temperatures and magnetic field quality assessment. In preparation of the future use for 450 GeV/c transfer to LHC and double batch extraction at 400 GeV/c for CNGS the tests comprised extractions of single bunches, twelve bunches in a single extraction and single bunches in a double extraction. The simulated and measured kick characteristics of the upgraded system are presented, along with results from uniformity calculations of the magnetic field after the modifications to accommodate the cooling circuitry. Further improvements will be discussed which are intended to make the system comply with the specifications for CNGS.  
 
MOPLT019 Experience Gained in the SPS for the Future LHC Abort Gap Cleaning injection, betatron, feedback, optics 575
 
  • W. Höfle
    CERN, Geneva
  Abort gap cleaning using a transverse damper (feedback) has been previously shown in the RHIC accelerator. We report on experimental results in the SPS, where the transverse damper was used to excite transverse oscillations on part of an LHC test beam, and by the induced losses, creating a practically particle free zone. It is proposed to use the same principle for abort gap cleaning in the LHC. For the LHC abort gap cleaning may be required at injection energy, during the ramp and at top energy. It is shown how the transverse excitation can be optimized taking into account the actual bandwidth of the damper systems and the possibility to fully modulate their input signal to match the beam batatron tune distribution. The cleaning efficiency and speed is estimated considering the porcesses involved, the cleaning (with damper) and the filling of the abort gap.  
 
MOPLT021 Attenuation and Emittance Growth of 450 GeV and 7 TeV Proton Beams in Low-Z Absorber Elements emittance, scattering, injection, simulation 581
 
  • V. Kain, B. Goddard, Y. Kadi, R. Schmidt
    CERN, Geneva
  The intensity of the LHC beams will be several orders of magnitude above the damage thresholds for equipment, at 7 TeV, but also already at injection energy of 450 GeV. Passive protection of the equipment against failures during beam transfer, injection and dumping of the beam with absorbers and collimators is foreseen to ensure safe operation. Since these protection devices must be robust in case of beam impact, low-Z materials such as graphite are favored. The reduction of the energy density of the primary beam by the absorber is determined by the attenuation of the beam due to nuclear collisions and the emittance growth of the surviving protons due to scattering processes. Absorbers with low density materials tend to be several meters long to ensure sufficient reduction of the transverse energy density of the impacting beam. The physics principles leading to attenuation and emittance growth for a hadron beam traversing matter are summarised, and FLUKA simulation results for 450 GeV and 7TeV proton beams on low-Z absorbers are compared with theoretical predictions. Design criteria for the LHC absorbers can be derived from these results. As an example, for the transfer line from SPS to LHC a short, low-Z absorber has been proposed to protect the LHC injection elements.  
 
MOPLT022 The Expected Performance of the LHC Injection Protection System injection, simulation, kicker, insertion 584
 
  • V. Kain, O.S. Brüning, L. Ducimetière, B. Goddard, M. Lamont, V. Mertens
    CERN, Geneva
  The passive protection devices TDI, TCDD and TCLI are required to prevent damage to the LHC in case of serious injection failures, in particular of the MKI injection kicker. A detailed particle tracking, taking realistic mechanical, positioning, injection, closed orbit and local optical errors into account, has been used to determine the required settings of the absorber elements to guarantee protection against different MKI failure modes. The expected protection level of the combination of TDI with TCLI, with the new TCLI layout, is presented. Conclusions are drawn concerning the expected damage risk level.  
 
MOPLT031 LHC Abort Gap Filling by Proton Beam collimation, radiation, injection, synchrotron 611
 
  • E.N. Shaposhnikova, S.D. Fartoukh, J.-B. Jeanneret
    CERN, Geneva
  Safe operation of the LHC beam dump relies on the possibility of firing the abort kicker at any moment during beam operation. One of the necessary conditions for this is that the number of particles in the abort gap should be below some critical level defined by quench limits. Various scenarios can lead to particles filling the abort gap. The relevant time scales associated with these scenarios are estimated for top energy where the synchrotron radiation losses are not negligible for uncaptured particle motion. Two cases are considered, both with RF on and RF off. The equilibrium distribution of lost particles in the abort gap defines the requirements for maximum tolerable relative loss rate and as a consequence the minimum acceptable longitudinal lifetime of the proton beam in collision.  
 
MOPLT038 Conceptual Design of the LHC Beam Dumping Protection Elements TCDS and TCDQ extraction, dumping, vacuum, instrumentation 629
 
  • W.J.M. Weterings, B. Goddard, B. Riffaud, M. Sans Merce
    CERN, Geneva
  The Beam Dumping System for the Large Hadron Collider, presently under construction at CERN, consists, per ring, of a set of horizontally deflecting extraction kicker magnets, vertically deflecting steel septa, dilution kickers and finally, a couple of hundred metres further downstream, an absorber block. A fixed diluter (TCDS) will protect the septa in the event of a beam dump that is not synchronised with the particle free gap or a spontaneous firing of the extraction kickers which will cause the beam to sweep over the septum. A mobile diluter block (TCDQ) will protect the superconducting quadrupole immediate downstream of the extraction as well as the arc at injection energy and the triplet aperture at top energy from bunches with small impact parameters. The conceptual design of the protection elements will be described, together with the status of the mechanical engineering.  
 
MOPLT039 QCD Explorer Based on LHC and CLIC-1 luminosity, electron, emittance, simulation 632
 
  • F. Zimmermann, D. Schulte
    CERN, Geneva
  Colliding 7-TeV LHC super-bunches with 75-GeV CLIC bunch trains can provide electron-proton collisions at very high centre-of-mass energies, opening up a new window into QCD. At the same time, this QCD explorer would employ several key components required for both an LHC upgrade and CLIC. We here present a possible parameter set of such a machine, study the consequences of the collision for both beams, and estimate the attainable luminosity.  
 
MOPLT042 Interaction of the CERN Large Hadron Collider (LHC) Beam with Solid Metallic Targets target, simulation, collider, heavy-ion 641
 
  • N.A. Tahir, D.H. Hoffmann
    GSI, Darmstadt
  • V. Fortov, I. Lomonosov, A. Shutov
    IPCP, Chernogolovka, Moscow region
  • B. Goddard, V. Kain, R. Schmidt
    CERN, Geneva
  • R. Piriz, M. Temporal
    Universidad de Castilla-La Mancha, Ciudad Real
  The LHC will operate at 7 TeV with a luminosity of 1034 cm-2s-1. This requires two beams, each with 2808 bunches. The nominal intensity per bunch is 1.1 1011 protons. The energy stored in each beam of 350 MJ could heat and melt 500 kg of copper. Protection of machine equipment in the presence of such powerful beams is essential. In this paper the mechanisms causing equipment damage in case of a failure of the machine protection system are discussed. An energetic heavy ion beam induces strong radial hydrodynamic motion in the target that drastically reduces the density in the beam heated region [*], leading to a much longer range for particles in the material. For the interaction of the LHC proton beams with a target a similar effect is expected. We carried out two-dimensional hydrodynamic simulations of the heating of a solid copper block with a face area of 2cm x 2cm irradiated by the LHC beam with nominal parameters. We estimate that after an impact of about 100 bunches the beam heated region has expanded drastically. The density in the inner 0.5 mm decreases by about a factor of 10. The temperature in this region is about 10 eV and the pressure about 15 GPa. The material in the heated region is in plasma state while the rest of the target is in a liquid state. The bulk of the following beam will not be absorbed and continue to tunnel further and further into the target. The results allow estimating the length of a sacrificial absorber, if such device should be installed for an LHC upgrade. A very interesting "spinoff" from this work would be the study of high-energy-density states of matter induced by the LHC beam, because a specific energy deposition of 200 kJ/g is achieved after 2.5 micros.

* N.Tahir et al., Phys. Rev. E, 63, 2001

 
 
MOPLT044 Longitudinal Positron Polarisation in HERA-II luminosity, optics, collider, quadrupole 644
 
  • E. Gianfelice-Wendt, D.P. Barber, F. Brinker, W. Decking, J. Keil, M. Vogt, F.J. Willeke
    DESY, Hamburg
  Following the installation of two more pairs of spin rotators in the course of the HERA Luminosity Upgrade, longitudinal positron spin polarisation has now been generated simultaneously at all three positron(electron) interaction points in HERA at the routine energy of 27.5 GeV. The maximum attained so far is 54 percent. The theoretical maximum for this configuration and in the presence of realistic errors is 57.0 percent. This is the first time in the history of high energy electron storage ring physics that the naturally occurring vertical polarisation has been, with the aid of spin rotators, converted to longitudinal polarisation at three interaction points simultaneously. We describe the measures needed to attain polarisation in light of the HERA Upgrade and the resulting recent performance.  
 
MOPLT045 Vacuum Induced Backgrounds in the New HERA Interaction Regions background, vacuum, interaction-region, radiation 647
 
  • M. Seidel, M.G. Hoffmann
    DESY, Hamburg
  After the rebuild of the HERA interaction regions the experimental detectors were limited by beam induced backgrounds. Four types of background mechanisms were observed and identified - proton gas scattering, lepton gas scattering, synchrotron radiation and proton beam-halo losses. With some refined beam steering methods it was possible to tune the synchrotron radiation background to acceptable limits. The remaining most important effect was the scattering of the beam particles, mostly the protons, at the residual gas. In this contribution we describe our systematic attempts to investigate the complex behavior of the beam gas background and the measures taken to improve the situation. This includes dynamic pressure profile simulations and measurements, experimental determination of the background sensitivity profile along the beamline, the pressure development with current and time, and residual gas analysis. The background conditions were finally improved due to long term conditioning with beam, modifications of internal masks which were heated by higher order mode losses and moderate improvements of the pumping speed at strategic locations.  
 
MOPLT055 RF Excitation of Linear and Curved Sections of the CRFQ Project radio-frequency, quadrupole, rfq, simulation 677
 
  • D. Davino
    Universita' degli Studi del Sannio, Benevento
  • L. Campajola, V.G. Vaccaro
    Naples University Federico II, Mathematical, Physical and Natural Sciences Faculty, Napoli
  • M.R. Masullo
    INFN-Napoli, Napoli
  • A. Ruggiero
    BNL, Upton, Long Island, New York
  The Circular Radiofrequency Quadrupole is basically a Linear Radio-Frequency Quadrupole completely bent on a circle. A 30-keV prototype is being presently designed and manufactured for testing of the fundamental principles within the scope of a collaboration between BNL and Italian research centers. The storage ring is made of a proton source, a Linear RfQ section 70 cm long, for injection and matching, and eight Curved sections also each about 70 cm long. The proton beam is provided by a modified RF source with electrostatic acceleration at the emittance, intensity and energy required by the beam dynamics.The design of the initial linear prototype is based on a 4-rods geometry having a beam gap diameter of 10mm, and circular 10mm diameters rods. The sector is placed in a 150mm diameter pipe, making it as a very compact structure. The dimensions of the device are adjusted to resonate at 202.56 MHz. A RF power source will be soon available to test the device. The paper describes the compact RF cells arrangement in the design of the two sections.  
 
MOPLT066 Induction Accelerating Cavity for a Circular Ring Accelerator induction, acceleration, synchrotron, linac 704
 
  • K. Torikai, Y.A. Arakida, T. Kono, K. Koseki, E. Nakamura, Y. Shimosaki, K. Takayama, T. Toyama, M. Wake
    KEK, Ibaraki
  • J. Kishiro
    JAERI/LINAC, Ibaraki-ken
  This paper reports details of an induction accelerating cavity employed for induction synchrotron POP experiments [*] using the KEK 12GeV PS. This cavity is the first induction cavity in the history of accelerator that is used in a circular ring. We focus our attention on crucial aspects distinguished from well-know properties of RF cavity. The single cavity is capable of generating an acceleration voltage of 2.5kV with a pulse width of 250ns, which is operated at a repetition　rate in the range of 667kHz - 882kHz. The cavity is driven by its own pulse modulator through a 25m long transmission cable of 125W, the end of which is connected with a matching resistance so as to minimize reflection in a wide range of frequency. Accelerating field characteristics are discussed and matching features of the cavity as a one-to-one transformer are presented. A longitudinal and transverse coupling impedance have been measured using a net-work analyzer.

* K.Takayama et al., 'POP Experiments of the Induction Synchrotron' in this conference

 
 
MOPLT071 EPICS Based Control System for the KOMAC RF System rfq, feedback, linac, vacuum 716
 
  • J.C. Yoon, J. Choi, K.M. Ha, J.H. Kim, J.M. Kim, J.-W. Lee
    PAL, Pohang
  This paper presents the RF control system for Korea Multi-purpose Accelerator Complex (KOMAC). KAERI (Korea Atomic Energy Research Institute) has been performing the project named KOMAC. As the 3nd phase of the project, 20MeV proton accelerating structure is under development. The new design is based on the use of VME based Multi-function modules connected to the specific low level RF Controllers(LLRF) via distributed I/O modules and Serial communication modules. The control system was based on EPICS (Experimental Physics and Industrial Control System) from the end of 2003. Installation and commissioning of the RF module is scheduled on 2004. Control system to integrated the RF System to the KOMAC control system is implemented. Hardware, software and various applications are developed to support the operation of RF Control system. This paper EPICS based control system for KOMAC RF  
 
MOPLT104 Quantitative Optimisation Studies of the Muon Front-End for a Neutrino Factory lattice, linac, target, emittance 776
 
  • S.J. Brooks
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  In a Neutrino Factory, short proton pulses hit a target, producing pions at widely varying angles and energies. Efficient pion capture is required to maximise the yield of decayed muons, which proceed via acceleration stages into a muon storage ring to produce neutrinos. This paper presents optimisation of a solenoidal decay channel designed for high-emittance pions, based on schemes from CERN and RAL. A non-linear tracking code has been written to run under an optimisation algorithm where every beamline element can be varied, which is then deployed as a distributed computing project. Some subsequent stages of muon beamline are also simulated, including RF and non-RF phase-rotation techniques and in one option, initial muon acceleration to 400MeV. The objective is to find optimal transmissions for each front-end concept.  
 
MOPLT109 Longitudinal Schottky Spectra of Bunched Beams synchrotron, antiproton, storage-ring, diagnostics 791
 
  • V. Balbekov, S. Nagaitsev
    Fermilab, Batavia, Illinois
  In this paper we derive an expression for longitudinal Schottky spectrum of a bunched beam in a stationary bucket. The expression is then used to calculate longitudinal emittance of the antiproton beam in the Fermilab Recycler ring. The Recycler beam is bunched longitudinally by a barrier-bucket rf waveform. Under certain bucket conditions, dependence of synchrotron frequency on particle energy becomes non-monotonic. It complicates the Schottky spectrum derivation and interpretation; we address these difficulties in our paper.  
 
MOPLT115 Numerical Simulations and Analyses of Beam-Induced Damage to the Tevatron Collimators simulation, dipole, collimation, superconducting-magnet 806
 
  • A. Drozhdin, N. Mokhov, D. Still
    Fermilab, Batavia, Illinois
  • V. Samulyak
    BNL, Upton, Long Island, New York
  Numerical simulations are performed to analyze the Tevatron collimator damage happened in December 2003 that was induced by a failure in the CDF Roman Pot detector positioning during the collider run. Possible scenarios of this failure resulted in an excessive halo generation and superconducting magnet quench are studied via realistic simulations using the STRUCT and MARS14 codes. It is shown that the interaction of a misbehaved proton beam with the collimators result in a rapid local heating and a possible damage. A detailed consideration is given to the ablation process for the collimator material taking place in high vacuum. It is shown that ablation of tungsten (primary collimator) and stainless steel (secondary collimator) jaws results in creation of a groove in the jaw surface as was observed after the December's accident.  
 
MOPLT148 Progress of the eRHIC Electron Ring Design electron, emittance, polarization, luminosity 887
 
  • F. Wang, M. Farkhondeh, W. Franklin, W. Graves, R. Milner, C. Tschalaer, J. Van der Laan, D. Wang, A. Zolfaghari, T. Zwart
    MIT/BLAC, Middleton, Massachusetts
  • D.P. Barber
    DESY, Hamburg
  • C. Montag, S. Peggs, V. Ptitsyn
    BNL, Upton, Long Island, New York
  • A.V. Otboev, Y.M. Shatunov
    BINP SB RAS, Novosibirsk
  • J. Shi
    KU, Lawrence, Kansas
  Over the past year, a baseline design of the electron ring for the eRHIC hadron-lepton collider has been developed.This site-specific design is based on the understanding of the existing RHIC machine performance and its possible upgrades.The design includes a full energy polarized electron beam injector to ensure operational reliability and to provide high integrated luminosity.The electron ring energy range is 5 to 10 GeV.The electron beam emittance, the electron beam path length and the interaction region optics have to be adjusted over a wide range to match the hadron beam of various species and variable energies.We describe the expected machine perfomance, the interaction region and the lattice design. We also discuss the possible approaches leading to the 1033 cm-2s-1 luminosity for the collisions between 10 GeV polarized electron beam and 250 GeV polarized proton beam.  
 
MOPLT153 Electron-Ion Collider at CEBAF: New Insights and Conceptual Progress ion, electron, luminosity, collider 893
 
  • Y.S. Derbenev, A. Afanasev, K. Beard, S.A. Bogacz, P. Degtiarenko, J.R. Delayen, A. Hutton, G.A. Krafft, R. Li, L. Merminga, M. Poelker, B.C. Yunn, Y. Zhang
    Jefferson Lab, Newport News, Virginia
  • P.N. Ostroumov
    ANL/Phys, Argonne, Illinois
  We report on progress in conceptual development of the proposed high luminosity (up to 1035/cm2s) and efficient spin manipulation (using figure 8 boosters and collider rings) Electron-Ion Collider at CEBAF based on use of polarized 5-7 GeV electrons in superconduction energy recovering linac (ERL with circulator ring, kicker-operated) and 30-150 GeV ion storage ring (polarized p, d. He3, Li and unpolarized nuclei up to Ar, all totally stripped). Ultra-high luminosity is envisioned to be achievable with short ion bunches and crab-crossing at 1.5 GHz bunch collision rate interaction points. Our recent studies concentrated on simulation of beam-beam interaction, preventing the electron cloud instability, calculating luminosity lifetime due to Touschek effect in ion beam and background scattering of ions, experiments on energy recovery at CEBAF, and other. These studies have been incorporated in the development of the luminosity calculator and in formulating minimum requirements to the polarized electron and ion sources  
 
MOPLT167 RHIC Operation with Longitudinally Polarized Protons polarization, resonance, injection, synchrotron 920
 
  • H. Huang, M. Bai, J. Beebe-Wang, M. Blaskiewicz, J.M. Brennan, K.A. Drees, W. Fischer, A.U. Luccio, W.W. MacKay, C. Montag, F.C. Pilat, V. Ptitsyn, T. Roser, T. Satogata, S. Tepikian, D. Trbojevic, J. Van Zeijts, A.Y. Zelinsky, S.Y. Zhang
    BNL, Upton, Long Island, New York
  Longitudinally polarized proton beams have been accelerated, stored and collided at 100GeV in the Relativistic Heavy Ion Collider (RHIC) to study spin effects in the hadronic reactions. The essential equipment includes four Siberian snakes, eight spin rotators and a fast relative polarimeters in each of the two RHIC rings as well as local polarimeters at the STAR and PHENIX detectors. This paper summarizes the performance of RHIC as a polarized proton collider.  
 
MOPLT170 eRHIC, Future Electron-ion Collider at BNL electron, ion, luminosity, linac 923
 
  • V. Ptitsyn, L. Ahrens, M. Bai, J. Beebe-Wang, I. Ben-Zvi, M. Blaskiewicz, J.M. Brennan, R. Calaga, X. Chang, E.D. Courant, A. Deshpande, A.V. Fedotov, W. Fischer, H. Hahn, J. Kewisch, V. Litvinenko, W.W. MacKay, C. Montag, S. Ozaki, B. Parker, S. Peggs, T. Roser, A. Ruggiero, B. Surrow, S. Tepikian, D. Trbojevic, V. Yakimenko, S.Y. Zhang
    BNL, Upton, Long Island, New York
  • D.P. Barber
    DESY, Hamburg
  • M. Farkhondeh, W. Franklin, W. Graves, R. Milner, C. Tschalaer, J. Van der Laan, D. Wang, F. Wang, A. Zolfaghari, T. Zwart
    MIT/BLAC, Middleton, Massachusetts
  • A.V. Otboev, Y.M. Shatunov
    BINP SB RAS, Novosibirsk
  The paper reviews the progress made lately in the design of eRHIC, proposed future electron-ion collider on the basis of the existing RHIC machine. The eRHIC aims to provide collisions of electrons and positrons on ions and protons in center mass energy range of 25-70 GeV. The goal luminosities are in 1032-1033 1/(s*cm2) values for e-p and in 1030-1031 1/(s*cm2) values for e-Au collisions. An essential design requirement is to provide longitudinally polarized beams of electrons and protons (and, possibly lighter ions) at the collision point. The eRHIC ZDR has been recently developed which considers various aspects of the accelerator design. An electron accelerator, which delivers about 0.5A polarized electron beam current in the electron energy range of 5 to 10 GeV, should be constructed at the BNL near existing ion rings of the RHIC collider and should intersect an ion ring at least in one of the available ion ring interaction regions. In order to reach the luminosity goals some upgrades in ion rings also would be required. Ways to reach lower beam emmittances (electron cooling) and higher beam intensities have to be realized.  
 
MOPLT171 A Pratical Demonstration of the CRFQ Storage Ring rfq, focusing, injection, storage-ring 926
 
  • A. Ruggiero
    BNL, Upton, Long Island, New York
  • L. Campajola, V.G. Vaccaro
    Naples University Federico II, Mathematical, Physical and Natural Sciences Faculty, Napoli
  • D. Davino
    Universita' degli Studi del Sannio, Benevento
  • M.R. Masullo
    INFN-Napoli, Napoli
  The Circular Radiofrequency Quadrupole (CRFQ) is a new concept of a storage and accelerator ring for intense beams of light and heavy ions, protons and electrons. It is basically a Linear Radio-Frequency Quadrupole completely bent on a circle. The advantages are expected to be equivalent to those of a Linear RFQ, namely higher beam intensity and smaller beam dimensions. Moreover, it is a more compact device when compared to conventional accelerators. A collaboration was created between Brookhaven National Laboratory, the University of Naples, the University of Sannio, and the INFN-Section of Naples (Italy) for the purpose of developing a proof of principle (PoP) of the CRFQ. During the initial stage the main goal is the demonstration of the curvature effect of the quadrupolar RFQ field. At that purpose, the project is actually conceived of three phases: (i) develop an adequate 30 keV proton source, (ii) design, manufacture and test a linear RFQ section, and (iii) design, manufacture and test a curved RFQ section, both operating at 200 MHz. The linear section acts as a matching with the ion source at one end, and the curved section at the other. The paper discusses mechanical and RF considerations during the design and experiment. The final goal of the collaboration is eventually to build enough curved sections to complete the storage ring where to demonstrate storage of 30 keV protons over long periods of time.  
 
MOPLT172 Quest for a New Working Point in RHIC injection, resonance, ion, simulation 929
 
  • R. Tomas, M. Bai, W. Fischer, V. Ptitsyn, T. Roser, T. Satogata
    BNL, Upton, Long Island, New York
  The beam-beam interaction is a limiting factor in RHIC's performance, particularly in proton operation. Changing the working point is a strategy to minimize the beam-beam effect and improve the performance of the machine. Experiments at injection energy and simulations have been performed for a set of working points in order to determine what are the best candidates.  
 
MOPLT176 Mechanism of Electron Multipacting with a Long Bunch Proton Beam electron, dipole, quadrupole, simulation 938
 
  • L. Wang, M. Blaskiewicz, J. Wei
    BNL, Upton, Long Island, New York
  • R.J. Macek
    LANL/LANSCE, Los Alamos, New Mexico
  The mechanism of electron multipacting in long bunched proton machine has been quantitatively described by the electron energy gain and electron motion. Some important parameters related to electron multipacting are investigated in detail. It is proved that multipacting is sensitive to beam intensity, longitudinal beam profile shape and transverse beam size. Agreement is achieved among our analysis, simulation and experiment.  
 
MOPLT179 Beam Scrubbing for RHIC Polarized Proton Opearation electron, injection, interaction-region, monitoring 947
 
  • S.Y. Zhang, W. Fischer, H. Huang, T. Roser
    BNL, Upton, Long Island, New York
  One of the intensity limiting factor of RHIC polarized proton beam is the electron cloud induced pressure rise. During the 2003 polarized proton run, a beam scrubbing study was performed. Actual beam scrubbing time was much less than the planned 2 hours. However, a non-trivial beam scrubbing effect was observed not only in the locations with highest pressure rise, but also in most of the single beam straight sections. This not only confirmed that beam scrubbing is indeed a countermeasure to the electron cloud, but also showed the feasibility of applying beam scrubbing in RHIC proton beam operation to allow for higher beam intensities. In this article, the results will be reported.  
 
TUYACH01 Laser-acceleration and Laser-cooling for Ion Beams ion, laser, target, acceleration 54
 
  • M. Roth, A. Blazevic, E. Brambrink, M. Geissel
    TU Darmstadt, Darmstadt
  • P. Audebert
    LULI, Palaiseaux
  • M. Bussmann, D. Habs, U. Schramm, J. Schreiber
    LMU, München
  • R. Clarke, S. Karsch, D. Neely
    CCLRC/RAL, Chilton, Didcot, Oxon
  • J.A. Cobble, J. Fernandez, M. Hegelich, S. Letzring
    LANL, Los Alamos, New Mexico
  • T.E. Cowan, J. Fuchs, A. Kemp, H. Ruhl
    University of Nevada, Reno, Reno, Nevada
  • K. Ledingham, P. McKenna
    Strathclyde University, Glasgow
  The acceleration or cooling of particles with lasers has been the subject of growing interest over the last years. Because of the huge difference in mass, the acceleration of ions was so far limited to thermal expansion from laser plasmas, driven by the hot electron temperature. In recent years, due to the development of short-pulse ultra-intense lasers, the manipulation of ions has now become possible. Especially the generation of high quality, intense ion beams from laser solid interaction has attracted large attention and is investigated at many laboratories world-wide. For the first time, intense, directed, low emittance beams of ions have been observed, having several MeV of particle energy right from the source. A wealth of applications including next generation ion sources can be envisioned. The talk will give an overview of the status of laser cooling and ion acceleration including the last experimental results. In addition, an overview of the current and future research activities will be presented.  
Video of talk
Transparencies
 
TUZBCH02 Beam Dynamics Challenges for Future Circular Colliders electron, luminosity, emittance, simulation 83
 
  • F. Zimmermann
    CERN, Geneva
  The luminosity of circular colliders rises with the beam intensity, until some limit is encountered, mostly due to head-on and long-range beam-beam interaction, due to electron cloud, or due to conventional impedance sources. These limitations can be alleviated, if not overcome, by a proper choice of beam parameters and by dedicated compensation schemes. Examples include the alternating crossing at several interaction points, electromagnetic wires, super-bunches, electron lenses, clearing electrodes, and nonlinear collimation. I illustrate the benefit from such mitigating measures for the Tevatron, the LHC, the LHC Upgrade, the VLHC, the super e+e- factories, or other projects, and I describe related research efforts at FNAL, KEK, BNL and CERN.  
Video of talk
Transparencies
 
TUXLH01 Machine Protection Issues and Strategies for the LHC beam-losses, injection, kicker, insertion 88
 
  • R. Schmidt, J. Wenninger
    CERN, Geneva
  For nominal beam parameters at 7 TeV/c, each of the two LHC proton beams has a stored energy of 350 MJ threatening to damage accelerator equipment in case of uncontrolled beam loss. Since the beam dump blocks are the only element of the LHC that can withstand the impact of the full beam, it is essential for the protection of the LHC that the beams are properly extracted onto the dump blocks in case of emergency. The time constants for failures leading to beam loss extend from 100 microseconds to few seconds. Several protection systems are designed to ensure safe operation, such as beam instrumentation, collimators and absorbers, and magnet protection. Failures must be detected at a sufficiently early stage and transmitted to the beam interlock system that triggers the beam dumping system. The strategy for the protection of the LHC will be illustrated starting from some typical failures.  
Video of talk
Transparencies
 
TUXLH02 HERA Performance Upgrade: Achievements and Plans for the Future lepton, luminosity, interaction-region, resonance 93
 
  • M.G. Minty
    DESY, Hamburg
  Having surpassed the design luminosity of 1.5 x 1031/cm2s already in 1997, an ambitious upgrade of the HERA proton-lepton collider was undertaken in 2000/2001 to provide both higher luminosity and longitudinally polarized lepton beams in the colliding beam experiments, H1 and ZEUS, and for the internal gas target experiment, HERMES. Routine operation following the upgrade has commenced. Initially experimental backgrounds limited the total beam currents so the number of colliding bunches was reduced while maintaining high single-bunch beam currents. With nominal, pre-upgrade, bunch currents the measured specific luminosity is 2.5 times higher than before, however about 15% smaller than design. Following modifications to alleviate the high backgrounds in 2003, HERA is now again operating with the design number of bunches and the total beam currents are being steadily increased. With only 40% of the total design current, peak luminosities of 2.5 x 1031/cm2s have been demonstrated with a longitudinal polarization of >40%. In this presentation the experiences from the upgrade commissioning will be reviewed. Plans for improvement and pronections for the future will be described.  
Video of talk
Transparencies
 
TUXLH03 RHIC Performance and Plans Towards Higher Luminosity and Higher Polarization electron, luminosity, ion, polarization 98
 
  • T. Satogata
    BNL, Upton, Long Island, New York
  RHIC is the first hadron collider consisting of two independent rings. It is designed to operate over a wide range of beam energies and species, including polarized protons, heavy ions, and asymmetric beam collisions. RHIC has produced physics data at four experiments since 1999 in runs that include gold-on-gold collisions at design beam energy (100 GeV/u), high-energy polarized proton-proton collisions (100 GeV on 100 GeV), and deuteron-gold collisions (100 GeV/u). Recent machine performance will be reviewed for high-luminosity gold-gold operations and polarized proton operations, including causes and solutions for known operational limits. Plans and progress for luminosity and polarization improvements, electron cooling, and the electron-ion collider eRHIC will be discussed.  
Video of talk
Transparencies
 
TUYLH03 Challenges facing the Generation of MW Proton Beams using Rapid Cycling Synchrotrons injection, electron, extraction, quadrupole 113
 
  • Y. Irie
    KEK, Ibaraki
  The MW proton source using rapid cycling synchrotron (RCS) has many challenging aspects, such as (1) large aperture magnets and much higher RF voltages per turn due to a low energy injection and a large and rapid swing of the magnetic field, (2) field tracking between many magnet-families under slightly saturated conditions, (3) RF trapping with fundamental and higher harmonic cavities, (4) H- charge stripping foil, (5) large acceptance injection and extraction straights, (6) beam loss collection, and (7) beam instabilities. These are discussed in details mainly on the basis of the J-PARC 3GeV RCS, which is under construction in Japan. Issues (3) to (7) are common with another scheme of MW spallation neutron source, i.e. full-energy linac + accumulator ring. Comparisons with the SNS design in the US are then made. Reliability/availability of these machines is very important theme which finally determines the successful operations. From the experiences in the existing machines, we will discuss the factors necessary toward the better performance.  
Video of talk
Transparencies
 
TUPKF004 First Results with a Fast Phase and Amplitude Modulator for High Power RF Application linac, klystron, simulation, RF-structure 959
 
  • D. Valuch, H. Frischholz, J. Tuckmantel
    CERN, Geneva
  • C. Weil
    AFT, Backnang
  In a high energy and high power superconducting proton linac, it is more economical to drive several cavities with a single high power transmitter rather than to use one transmitter per cavity. This option has however the disadvantage of not permitting to individually control each cavity, which potentially leads to instabilities. Provided that it can be built at a reasonable cost, a fast phase & amplitude modulator inserted into each cavity feeder line can provide the necessary control capability. A prototype of such a device has been built, based on two fast and compact high power RF phase-shifters, magnetically biased by external coils. The design is described, together with the results obtained at high and low power levels.  
 
TUPKF006 Custom Design of Medium Energy Linear Accelerator Systems linac, electron, ion, bunching 965
 
  • K. Dunkel, M. Pekeler, C. Piel, H.P. Vogel, P. vom Stein
    ACCEL, Bergisch Gladbach
  Based on customer requirements ACCEL Instruments is designing and building medium energy turn-key Linear Accelerator Systems for scientific applications. Within this paper design and performance of third generation synchrotron light source electron injector linacs will be presented. Further the design of a medium energy light ion linear accelerator will be discussed. This light ion accelerator is designed with independently phased superconducting rf cavities for cw operation and acceleration of different particle species and a variable Energy output.  
 
TUPKF013 Studies on Maximum RF Voltages in Ferrite-tuned Accelerating Cavities synchrotron, ion, antiproton, acceleration 985
 
  • K. Kaspar, H.G. Koenig, T. Winnefeld
    GSI, Darmstadt
  The GSI SIS100 project requires very high accelerating voltages. With ferrite-tuned synchrotron cavities the gap voltage is often strongly limited by the Q-loss effect appearing at medium dc bias fields. At low bias fields, considerably higher voltages can be reached, however. The maximum usable amplitudes over the bias region have been studied. At zero bias, the ferrites could be driven to more than a factor 3 above the Q-loss limit. Except overheating, no other problems appeared. With increasing bias, the maximum amplitudes decrease continuously to the Q-loss level. In this fall-off region there is still a tuning factor up to 2.5 available, with rf flux densities by at least a factor 2 above the Q-loss level. Measurements on small samples of the ferrite material used in the GSI cavities could be verified very well in a full-size cavity, for the most part. The tests were mainly limited by the available anode voltage and the fear of damaging the cavity. It seems possible, to generalize the main results for other ferrite materials, also. Based on the results, a possible scenario for the SIS100 rf system is given. Additionally, the results lead to an alternative cavity design for higher voltages, which is described as well.  
 
TUPKF015 Status of the Superconducting CH-Structure acceleration, ion, linac, simulation 991
 
  • H. Podlech, H. Deitinghoff, H. Klein, H. Liebermann, U. Ratzinger, A.C. Sauer, R. Tiede
    IAP, Frankfurt-am-Main
  H-mode cavities (IH-DTL, IH-RFQ, 4-Vane-RFQ) have been developed and operated successfully during the last decades for ion acceleration. At the IAP Frankfurt a new type of H-mode cavity, the CH-structure is under development. This multi cell drift tube cavity is operated in the TE21- mode. Due to its mechanical rigidity, room temperature as well as superconducting versions can be realized. Superconducting CH-structures might be used especially for cw operated linacs in nuclear research facilites and applied research projects like XADS or IFMIF. A superconducting 352 MHz CH-structure (beta=0.1) with 19 gaps will be available for first tests in 2004. We present the status of the cavity and of the new cryo laboratory in Frankfurt.  
 
TUPKF019 Recent Developments on Superconducting b035 and b015 Spoke Cavities at IPN for Low and Medium Energy Sections of Proton Linear Accelerators. linac, pick-up, tandem-accelerator, vacuum 1003
 
  • G. Olry, J.-L. Biarrotte, S. Blivet, S. Bousson, F. Chatelet, D. Gardès, N. Hammoudi, T. Junquera, J. Lesrel, C. Miélot, A.C. Müller, D. Ruffier, H. Saugnac, P. Szott, J.P. Thermeau
    IPN, Orsay
  Spoke cavities studies leaded by IPN-Orsay, for both XADS and EURISOL projects, are fully integrated within the 5th and 6th European Framework Programs. During 2003, several tests have been performed on the first b035 spoke cavity prototype. They have demonstrated the great potential of this type of cavity in term of RF performances (Eacc max=12.5 MV/m at T=4.2 K) and mechanical behavior (very low sensitivity to errors fabrication, good stiffness…). Following the upgrade of our cryogenic facility, we have tested, this spring, the cavity at 2 K. These new results will be presented in this paper. In parallel, the fabrication of a new spoke cavity (2-gap, 352 MHz, b015) has begun in January. While keeping the same geometry than that of the b035 cavity, we carried out significant changes on the coupler port and stiffening system designs. We report here in particular, RF calculations concerning the new location of the coupler port (in order to minimize losses due to magnetic field) and also, mechanical calculations about the new stiffening ring. Finally, we will present the preliminary thought on modular cryomodule which are based on the ?short? cryomodule concept used with the Quarter Wave Resonators for the SPIRAL-2 project.  
 
TUPKF022 Constructionand Testing of the Beta=0.31, 352 MHz Superconducting Half-wave Resonator for the SPES Project linac, vacuum, quadrupole, coupling 1012
 
  • A. Facco, W. Lu, F. Scarpa
    INFN/LNL, Legnaro, Padova
  • E. Chiaveri, R. Losito
    CERN, Geneva
  • V. Zviagintsev
    TRIUMF, Vancouver
  The interest in low- and medium- beta superconducting cavities is presently focused to future high intensity proton, deuteron and heavy ion linacs. A particular application is acceleration of cw and pulsed beams of variable q/A, which requires cavities with a small number of gaps and excellent mechanical stability. We have designed and constructed a 2 gap, 352 MHz SC half wave cavity aiming to similar characteristics and fitting the requirements of the intermediate-beta section of the LNL-SPES driver. The status of the project and the first test results will be presented.  
 
TUPKF033 Cryogenic Performance of the Prototype Cryomodule for ADS Superconducting LINAC linac, alignment, synchrotron, radiation 1033
 
  • N. Ohuchi, E. Kako, S. Noguchi, T. Shishido, K. Tsuchiya
    KEK, Ibaraki
  • N. Akaoka, H. Kobayashi, N. Ouchi, T. Ueno
    JAERI/LINAC, Ibaraki-ken
  • T. Fukano
    Nippon Sanso Corporation, Tokyo
  • H. Hara, M. Matsuoka, K. Sennyu
    MHI, Kobe
  A prottype cryomodule containing two 9-cell superconducting cavities of b=0.725 and f=972MHz is being constructed under the collaboration of Japan Atomic Energy Research Institute (JAERI) and High Energy Accelerator Research Organization (KEK) on the development of superconducting LINAC for Accelerator Driven System (ADS). Cryogenic performances of the cryomodule and 2K He-system will be reported.  
 
TUPKF035 RF System for Compact Medical Proton Synchrotron synchrotron, acceleration, impedance, radiation 1039
 
  • Z. Fang, K. Egawa, K. Endo, S. Yamanaka
    KEK, Ibaraki
  • Y. Cho, T. Fusato, T. Hirashima
    DKK, Kanagawa
  The rf system has been developed for the compact medical proton synchrotron. The rf system will be operated in pulse mode with the fundamental rf frequency sweeping from 1.6 to 15 MHz during the acceleration time of 5 ms. The required rf cavity voltage is a function of acceleration time too, with the voltage of fundamental varying from 13 to 6 kV. Besides, high order harmonics are also considered to apply to the rf system, and the cavity peak voltage varying from 20 to 9 kV during the acceleration time is expected. The performance of the rf system is being studied and will be presented.  
 
TUPKF036 RF Property of the Prototype Cryomodule for ADS Superconducting Linac linac, vacuum, coupling, simulation 1042
 
  • E. Kako, S. Noguchi, N. Ohuchi, T. Shishido
    KEK, Ibaraki
  • N. Akaoka, H. Kobayashi, N. Ouchi, T. Ueno
    JAERI/LINAC, Ibaraki-ken
  • H. Hara, M. Matsuoka, K. Sennyu
    MHI, Kobe
  A prototype cryomodule containing two 9-cell superconducting cavities of beta=0.725 and frequency=972MHz is being constructed under the collaboration of Japan Atomic Energy Research Institute (JAERI) and High Energy Accelerator Research Organization (KEK) on the development of superconducting LINAC for Accelerator Driven System (ADS). Design and performance of RF components will be reported.  
 
TUPKF037 Multi-harmonic RF Acceleration System for a Medical Proton Synchrotron acceleration, synchrotron, feedback, impedance 1045
 
  • K. Saito, M. Katane, K. Kobayashi, K. Masui, K. Moriyama, H. Nishiuchi, H. Sakurabata, H. Satomi
    Hitachi, Ltd., Power & Industrial Systems R&D Laboratory, Ibaraki-ken
  We have developed an RF accelerating system for medical proton synchrotron. The RF cavity is a tuning-free wideband type, loaded with FINEMET cores, which is driven by a solid-state RF power amplifier with operation frequency range between 1MHz and 10MHz. Multi-harmonic RF acceleration scheme has been realized with the RF control system, to reduce beam loss by space-charge effect in low energy region. The original techniques for high-speed digital signal processing and high-precision RF signal processing have been applied, in order to fulfill feedback control of the frequency, phase and amplitude of the second and third harmonic RF signals as well as the fundamental one.  
 
TUPKF058 Test Results for the New 201.25 MHz Tetrode Power Amplifier at LANSCE linac, power-supply, electron, impedance 1078
 
  • J.T.M. Lyles, S. Archuletta, J. Davis, L. Lopez, G. Roybal
    LANL/LANSCE, Los Alamos, New Mexico
  A new RF amplifier has been constructed for use as the intermediate power amplifier stage for the 201.25 MHz Alvarez DTL at LANSCE. It is part of a larger upgrade to replace the entire RF plant with a new generation of components. The new RF power system under development will enable increased peak power with higher duty factor. The first tank requires up to 400 kW of RF power. This can be satisfied using the TH781 tetrode in a THALES cavity amplifier. The same stage will be also used to drive a TH628 Diacrode? final power amplifier for each of the three remaining DTL tanks. In this application, it will only be required to deliver approximately 150 kW of peak power. Details of the system design, layout for DTL 1, and test results will be presented.  
 
TUPLT007 The CERN-SPL Chopper Concept and Final Layout vacuum, quadrupole, linac, antiproton 1141
 
  • F. Caspers, Y. Cuvet, J. Genest, M. Haase, M. Paoluzzi, A. Teixeira
    CERN, Geneva
  The fast chopper for the CERN SPL (Superconducting Proton Linac) consists of a double meander structure with a beta (v/c) value of 8 % printed on an alumina substrate for the deflecting plates. Each chopper unit is 50 cm long and housed in a quadrupole magnet surrounding the vacuum chamber. The deflecting plates are operated simultaneously in a dual mode, namely traveling wave mode for frequencies above about 10 MHz and as quasi electro-static deflectors below. The deflecting structures are water-cooled to handle heating from beam losses as well as from the deflecting signal. A detailed mechanical layout is presented including the tri-axial feeding and termination technique as well as a discussion of the drive amplifier  
 
TUPLT009 Trajectory Correction Studies for the CNGS Proton Beam Line injection, quadrupole, simulation, extraction 1147
 
  • M. Meddahi, W. Herr
    CERN, Geneva
  The performance of the proposed trajectory correction scheme for the CNGS proton beam line was checked with an advanced simulation program. It was first investigated whether the scheme will be sufficient, and if some correctors or monitors could be suppressed in order to reduce the cost. The correction scheme was in particular tested for the case of faulty correctors or monitors. Possible critical scenarios were identified, which may not be visible in a purely statistical analysis. This part of the analysis was largely based on the experience with trajectory and orbit correction problems encountered in the SPS and LEP. The simulation of the trajectory correction procedure was done using recently developed software.  
 
TUPLT010 Aperture and Stability Studies for the CNGS Proton Beam Line target, extraction, injection, dipole 1150
 
  • M. Meddahi, W. Herr
    CERN, Geneva
  The knowledge of the beam stability at the CNGS target is of great importance, both for the neutrino yield and for target rod resistance against non-symmetric beam impact. Therefore, simulating expected imperfections of the beam line elements and possible injection errors into the CNGS proton beam line, the beam spot stability at the target was investigated. Moreover, the mechanical aperture of the CNGS proton beam line was simulated and the results confirmed that the aperture is tight but sufficient.  
 
TUPLT035 Online Calculation of the Beam Trajectory in the HERA Interaction Regions quadrupole, alignment, interaction-region, synchrotron 1222
 
  • F. Brinker
    DESY, Hamburg
  During the HERA luminosity upgrade the new super conducting mini beta quadrupoles have been placed inside the experiments for final focussing and separation of the lepton and proton beams. The synchrotron radiation of up to 12 kW produced in these magnets passes through the detector and is absorbed behind the experiments. In order to avoid background events from synchrotron radiation it is a mandatory to adjust precisely the beam trajectory before and inside the detector. A procedure has been developed to calculate the trajectory in the interaction regions. With a beam-based alignment the offsets of the beam with respect to the quadrupoles is measured. From this measurement the offsets of the quadrupoles and of the beam position monitors are fitted. With the knowledge of these offsets the trajectory of the beam is calculated with high precision. The display of the trajectory is online available as an operational tool for beam steering and background optimization.  
 
TUPLT043 Status of the Cooler Synchrotron COSY-Juelich injection, polarization, electron, dipole 1246
 
  • B. Lorentz, U. Bechstedt, J. Dietrich, R. Eichhorn, R. Gebel, A. Lehrach, R. Maier, D. Prasuhn, A. Schnase, H. Schneider, R. Stassen, H. Stockhorst, R. Tölle
    FZJ/IKP, Jülich
  The cooler synchrotron COSY accelerates and stores unpolarized and polarized protons and deuterons in the momentum range between 300 MeV/c to 3.65 GeV/c. To provide high quality beams, an Electron Cooler at injection and a Stochastic Cooling System from 1.5 GeV/c up to maximum momentum are available. Vertically polarized proton beams with a polarization of more than 0.80 are delivered to internal and external experimental areas at different momenta. Externally, the maximum momentum is up to date restricted to approximately 3.4 GeV/c by the extraction elements installed in COSY. In 2003 deuteron beams with different combinations of vector and tensor polarization were made available for internal and external experiments. An rf dipole was installed, which is used to induce artificial depolarizing resonances. It can be used for an accurate determination of the momentum of the stored beams. The status of the cooler synchrotron COSY is presented and future plans are discussed.  
 
TUPLT045 Separatrix Formalism Applied to Linacs Accelerating Particles with Different Charge to Mass Ratio linac, acceleration, space-charge, simulation 1252
 
  • A. Bogdanov, R. Maier, Y. Senichev
    FZJ/IKP, Jülich
  We have developed separatrix formalism for superconducting linear accelerators. This method allows optimizing the quasi-synchronous velocity behavior along a linac. It gives a great advantage in acceleration of particles with different charge to mass ratio. In the article design optimization of structure supposed to accelerate different particles is presented. As an example for numerical simulation superconducting injector COSY is taken.  
 
TUPLT046 Luminosity Considerations for Internal and External Experiments at COSY target, luminosity, injection, extraction 1255
 
  • A. Lehrach, U. Bechstedt, J. Dietrich, R. Eichhorn, R. Gebel, B. Lorentz, R. Maier, D. Prasuhn, H. Schneider, R. Stassen, H. Stockhorst, R. Tölle
    FZJ/IKP, Jülich
  • A. Schnase
    JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  The future physics program at the Cooler-Synchrotron COSY in Jülich requires intense beams to provide high luminosities up to 1032cm-2s-1 for internal and external experiments. In 2003 the number of unpolarized protons could significantly be increased up to the theoretical space charge limit of COSY. This was achieved by careful study and adjustment of all subsystems in the accelerator chain of COSY. The intensities for polarized proton beams are at best an order of magnitude lower compared to one for unpolarized beams, depending on the beam current provided the injector cyclotron. Still there is some potential for further enhancement of polarized beam intensities. In this paper, luminosity considerations for polarized and unpolarized beams at COSY are presented taking into account different machine cycles and operation modes for internal and external experimental set-ups.  
 
TUPLT049 Triple-spoke Cavities in FZJ simulation, resonance, vacuum, coupling 1261
 
  • E. Zaplatin, W. Braeutigam, R. Maier, M. Pap, M. Skrobucha, R. Stassen, R. Tölle
    FZJ/IKP, Jülich
  We report the situation with superconducting triple-spoke cavity activities at the research center FZJ in Juelich. The Nb prototype of the 700 MHz, beta=0.2 cavity is already in fabrication and should be tested this year. This work has been initiated for the European Spallation Source project. In the frames of the new European project of High Intensity Pulsed Proton Injector the 352 MHz, beta=0.48 cavity is under developments. This cavity should be designed, built and tested in the Lab within next few years.  
 
TUPLT053 Recent Evolutions in the Design of the French High Intensity Proton Injector (IPHI) rfq, diagnostics, linac, vacuum 1273
 
  • P.-Y. Beauvais
    CEA/DSM/DAPNIA, Gif-sur-Yvette
  In 1997, the two French National Research Agencies (CEA and CNRS) decided to collaborate in order to study and construct a prototype of the low energy part of a High Power Proton Accelerator (HPPA). The main objective of this project (the IPHI project), is to allow the French team to master the complex technologies used and the control concepts of the HPPAs. Recently, a collaboration agreement was signed with the CERN and led to some evolutions in the design and in the schedule. The IPHI design current was maintained at 100 mA in Continuous Wave mode. This choice should allow to produce a high reliability beam at reduced intensity (typically 30 mA) tending to fulfill the Accelerator Driven System requirements. The output energy of the Radio Frequency Quadrupole (RFQ), originally set to 5 MeV, was reduced to 3 MeV, allowing then the adjunction and the test in pulsed mode of a chopper line developed by the CERN for the Superconducting Proton Linac (SPL). In a final step, the IPHI RFQ and the chopper line should become parts of the SPL injector. In this paper, the IPHI project evolutions are reported as well as the construction and operation schedule.  
 
TUPLT070 Study of a Linac Booster for Proton Therapy in the 30-62 MeV Energy Range linac, cyclotron, booster, impedance 1312
 
  • V.G. Vaccaro, A. D'Elia, M.R. Masullo
    Naples University Federico II and INFN, Napoli
  • D. Capasso, S. Lanzone
    Naples University Federico II, Napoli
  • T. Clauser, A. Rainò
    INFN-Bari, Bari
  • C. De Martinis, D. Giove, M. Mauri
    INFN/LASA, Segrate (MI)
  • V. Variale
    Bari University, Science Faculty, Bari
  Recent results in accelerator physics have shown the feasibility of a coupling scheme between a cyclotron and a linac for proton acceleration. Cyclotrons with energies up to 30 MeV, mainly devoted to radioisotopes production, are available in a large number of medical centres. These two evidences have suggested the idea to study and design a linac booster able to increase the initial proton energy up to the values required for the treatment of tumors, like the ocular ones. The main challenge in such a project is related to meet the requirements arising from the beam dynamics with the constrains due both to the mechanical structures and tolerances and to the heat dissipation mechanism chosen in the design. In this paper we will review the rationale of the project and we will discuss the basic design of a compact 3 Ghz linac with a new approach to the cavities used in a SCL (Side Coupled Linac) structure  
 
TUPLT079 Opposite Field Septum Magnet System for the J-PARC 50GeV Ring Injection septum, injection, synchrotron, vacuum 1339
 
  • I. Sakai, Y. Arakaki, K. Fan, Y. Mori, M. Muto, Y. Saitou, Y. Shirakabe, M. Tomizawa, M. Uota
    KEK, Ibaraki
  • K. Gotou, Y. Morigaki, A. Nishikawa, M. Takahashi
    IHI/Yokohama, Kanagawa
  • H. Mori, A. Tokuchi
    NICHICON, Shiga
  For the injection/extraction system of the high energy high intensity proton synchrotrons, high field wide aperture thin septum magnets are required. To solve these tight problems, new design concept of opposite-field septum magnet system has been invented. The same grade of opposite magnetic field is produced both inside and outside of the septum. The electromagnetic force and leakage flux around the septum conductor are cancelled out each other. The magnetic field of the circulating beam side is compensated by two sub-bending magnets set on the up-stream and down-stream of the opposite fields septum magnet. The beam-separation angle per magnet length is twice as large as normal septum magnet and the two sub-bending magnets also have a role to extend the injection/extraction angle. The newly developed method of the opposite field septum magnets system.is applied to the injection septum magnets for the J-PARC 50-GeV proton synchrotron to get the sufficient injection angle and clearance for low loss injection. The thin septum thickness and larger kick angle at the septum magnet can be obtained by the new system, which is applicable to many accelerators.  
 
TUPLT085 J-PARC Construction and its Linac Commissioning linac, synchrotron, quadrupole, site 1351
 
  • Y. Yamazaki
    JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  The J-PARC(Japan Proton Accelerator Research Complex) accelerator is under construction in JAERI Tokai site. The beam commissioning will be started there by the end of 2006. Prior to this, the front end of the linac was beam-commissioned in 2003 at KEK. The negative hydrogen beam with a peak current of 30 mA was accelerated up to 20 MeV by the first tank of three DTL's following the 3-MeV RFQ linac. The 324-MHz DTL contains the electro quadrupole magnets with water-cooling channels specially fabricated by means of electroforming and wire-cutting technologies. The construction status of the J-PARC accelerator is also presented.  
 
TUPLT089 Status of PEFP 3MeV RFQ Development rfq, klystron, vacuum, scattering 1363
 
  • Y.-S. Cho, B.-H. Choi, S.-H. Han, J.-H. Jang, Y.H. Kim, H.-J. Kwon, C.-B. Shim
    KAERI, Daejon
  In the PEFP (Proton Engineering Frontier Project), a 350MHz, 3MeV RFQ (Radio Frequency Quadrupole) has been developed and tested. The tuning results showed that the resonant frequency is somewhat higher than 350MHz and other methods in addition to slug tuners should be used to tune the cavity correctly. To check the cavity characteristics, high power RF test has been done. The required peak RF power is 600kW and pulse width, repetition rate for initial test are 100 micro-s, 10Hz respectively. To solve the problems in PEFP RFQ, the upgrade design of 3MeV RFQ has been decided. The main concept of this upgrade design is constant vane voltage profile with the same length of RFQ. The other parameters (350MHz, 3MeV, 20mA) are the same with the previous RFQ. With constant vane voltage profile, fabrication of RFQ can be easier, and with the same mechanical dimension, other parts such as vacuum pumping station can be re-used. In this paper, the test results of the PEFP RFQ, and the details of beam dynamics design/engineering design of upgrade RFQ will be presented.  
 
TUPLT090 Combined Beam Dynamics Study of the RFQ and DTL for PEFP rfq, quadrupole, emittance, simulation 1366
 
  • J.-H. Jang, Y.-S. Cho, H.-J. Kwon
    KAERI, Daejon
  One of the goals of the Proton Engineering Frontier Project (PEFP) is to get 20 MeV proton beams of 20 mA through a 3 MeV RFQ and a 20 MeV DTL. This work is related to the combined beam dynamics study of the low energy proton accelerators in order to test the validity of the connection of the independently designed structures as well as to study the MEBT for beam transportation.  
 
TUPLT091 Fabrication Status of the PEFP 20 MeV DTL vacuum, quadrupole, site, pick-up 1369
 
  • M.-Y. Park, Y.-S. Cho, J.-H. Jang, Y.H. Kim, H.-J. Kwon
    KAERI, Daejon
  The PEFP (Proton Engineering Frontier Project) 20 MeV DTL have been constructed in KAERI site. The fabrication of the first tank is finished and the DT installation is in the process. We choose the pool-type electromagnets as the focusing magnet and 50 DTs will be installed on first tank. We tested the winding schemes of copper coils on the iron core and measured the magnetic field saturation.In this paper, the results of the tank fabrication and quadrupole magnet test are presented.  
 
TUPLT092 Optics and Magnet Design for Proton Beam Transport Line at PEFP optics, multipole, dipole, extraction 1372
 
  • H.-S. Kang, H.S. Han, S.H. Jeong, Y.G. Jung, D.E. Kim, M. Kim, H.G. Lee, T.-Y. Lee, H.S. Suh
    PAL, Pohang
  The PEFP proton linac is designed to have two proton beam extraction lines at the 20-MeV and 100-MeV end, respectively. Each extraction line has 5 to 6 beamlines for proton beam users. The proton beam transport system for users? experiments will be prepared for this purpose. At the beginning, the beam optics for the proton beam transport system is designed with the TRACE code. The optics should be designed so as to meet the users? various requirements which might be to control the beam size and intensity at the beam target, and the timing of the proton beam. The magnet to distribute the proton beam to many beamlines is an AC magnet which has an AC frequency of 15 Hz, and is powered with a programmable AC power supply. In this paper, the result of the optics design will be presented and the magnet design will be described.  
 
TUPLT096 RFQ Low Level RF System for the PEFP 100MeV Proton Linac rfq, feedback, linac, simulation 1381
 
  • I.H. Yu, M.-H. Chun, K.M. Ha, Y.J. Han, W.H. Hwang, M.H. Jeong, H.-S. Kang, D.T. Kim, S.-C. Kim, I.-S. Park, J.S. Yang
    PAL, Pohang
  • Y.-S. Cho, K.T. Seol
    KAERI, Daejon
  The 100MeV Proton linear accelerator (Linac) for the PEFP (Proton Engineering Frontier Project) will include a 3MeV, 350MHz RFQ(Radio-Frequency Quadrupole) Linac. The RFQ accelerates a 20mA proton beam from 50keV to 3MeV. The low level RF system for RFQ provides field control. In addition to field control, it provides cavity resonance control. An accelerator electric field stability of ± 1% in amplitude and ± 1° in phase is required for the RF system. The low level RF system has been designed and is now being fabricated.  
 
TUPLT098 Vertical Beam Motion in the AGOR Cyclotron beam-losses, resonance, cyclotron, betatron 1384
 
  • M.A. Hofstee, S. Brandenburg, H. Post, W.K. van Asselt
    KVI, Groningen
  Large-scale vertical excursions have been observed in the AGOR cyclotron for light ionbeams at energies close to the focussing limit (E/A =200 Q/A MeV per nucleon). With increasing radius the beam gradually moves down out of the geometrical median plane by several mm, leading to internal beamlosses. It was concluded that this effect is caused by a vertical alignment error of the coils combined with the weak vertical focussing for the beams concerned. Moving the main coils by a total of 0.37 mm has significantly improved the situation at large radii, but results in internal beamlosses for certain beams at small radii due to a large upward excursion. A systematic study of the vertical beam dynamics as a function of beam particle and energy will be presented. Possible causes and solutions will be discussed.  
 
TUPLT112 Radiation Damage to the Elements of the Nuclotron-type Dipole of SIS100 ion, dipole, vacuum, beam-losses 1408
 
  • E. Mustafin, G. Moritz, G. Walter
    GSI, Darmstadt
  • L. Latysheva, N. Sobolevskiy
    RAS/INR, Moscow
  Radiation damage to various elements of the Nuclotron-type dipole of SIS100 sensitive to irradiation was calculated. Among the elements of consideration were the superconducting cables, insulating materials, ceramic insertions and high-current by-pass diodes. The Monte-Carlo particle transport code SHIELD was used to simulate propagation of the lost ions and protons together with the products of nuclear interactions in the material of the elements. The results for the proton projectiles were cross-checked using the particle transport code MARS, and a good agreement between the codes were found. It was found that the lifetime of the organic materials under irradiation are much more restrictive limit for the tolerable level of beam particle losses than the danger of the quench events.  
 
TUPLT113 Technicalities for a Novel Medium Energy Ion Accelerator ion, positron, vacuum, heavy-ion 1411
 
  • V. Gorev
    RRC Kurchatov Institute, Moscow
  Transmutation of radioactive waste,high-intensity pulsed sources of fast neutrons,problem of inertially-confined fusion and a lot of different problems of science and technology put increased demands on the linear high power medium energy proton and heavy ion accelerators.But these accelerators are presently massive,huge and very expansive,which restrict now and in a near future their wide use and motivates the study of altenetive methods to achieve the design current,power and economic characteristics.This report decribes the present reseach on attaining high power medium energy ion beams,using novel idea for accelerator design.Theoretical proposal and preliminary conceptual design for the accelerator,based on a principle of free flying ion emitter("ballistic anode"),were discussed first a few years ago.The principle involves a high potencial difference generated only for a short time in the special vacuum chamber,but not steady-state conditions.Now,we would like to discuss next problems:1.technicalities of the ballistic anode design,both for proton and heavy ion beams generation.2 pulse power multiplication.3.high current sources for charge pumping of the ballistic anode.4 experimental modelling.  
 
TUPLT137 Comparative Simulation Studies of Electron Cloud Build-up for ISIS and Future Upgrades simulation, electron, injection, synchrotron 1446
 
  • G. Bellodi
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  Electron cloud effects currently limit the performance of several proton accelerators operating with high beam current. Although ISIS, the 160 kW 70-800 MeV proton synchrotron at the Rutherford Appleton Laboratory (UK), has never appeared to be affected by the problem in its 15 years of operations, e-p instabilities could potentially be a cause of concern for future machine upgrades to higher beam powers. In this paper we review the present status of simulations for ISIS and compare it to preliminary results for two upgrade options: a 0.5MW 180-800 MeV scheme and a 1MW 0.8-3 GeV scheme with an additional synchrotron using ISIS as a booster (see C. Prior et al., ISIS megawatt upgrade plans, in Proceedings of the 2003 Particle Accelerator Conference PAC 2003, Portland, Or, USA).  
 
TUPLT138 A Fast Beam Chopper for Next Generation High Power Proton Drivers emittance, linac, ion, beam-transport 1449
 
  • M.A. Clarke-Gayther
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  The identification and development of a successful beam chopper design is regarded as key for the European Spallation Source (ESS), and for all next generation high intensity proton driver schemes that adopt the linac-accumulator ring configuration. A description is given of refinements to the beam line design of a 'Tandem' chopper system, developed to address the requirements of the ESS. Particle tracking using the 'General Particle Tracer' (GPT) code has enabled efficient optimisation of beam apertures, and the analysis of beam power density distributions on chopper beam dumps. Preliminary results of 'proof of principle' testing on prototype fast, and slower transition high voltage pulse generators, are presented.  
 
TUPLT140 Redesign of the ISIS Main Magnet Power Supply Storage Choke power-supply, coupling, synchrotron, insertion 1455
 
  • A.J. Kimber, J.W. Gray, A. Morris
    CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
  The ISIS facility, based at the Rutherford Appleton Laboratory in the UK, provides intense pulsed neutron and muon beams for condensed matter studies. As part of the facilities upgrade and refurbishment program, the 1MJ storage choke which forms part of the main magnet power supply system, will be replaced with a number of smaller units. The present storage choke, which consists of a split secondary winding transformer, is incorporated into a series-parallel resonant circuit known as the 'white circuit'. This circuit ensures that each magnet receives identical currents, but is not subjected to excessive voltages. Although the storage choke is essentially a transformer, its secondary magnetising inductance is relatively low and a precisely defined value. This paper discusses the design and development of ten smaller units which will eventually replace the present equipment, and the testing of a one fifth scale model, which will be used to prove the technology.  
 
TUPLT142 Status of Design of Muon Beamline for the Muon Ionisation Cooling Experiment emittance, target, quadrupole, dipole 1461
 
  • K. Tilley
    CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
  The MICE collaboration proposes to install a Muon Ionisation Cooling Experiment at the ISIS facility, at Rutherford Appleton Laboratory. This experiment will be the first demonstration of ionisation cooling as a means to reduce the large transverse emittance of the muon beam, produced during the early stages of a neutrino factory. In order to permit a realistic demonstration of cooling, a source of muons must be produced, possessing particular qualities, notably in emittance and momenta. This paper describes the present design for the muon beamline source, and the plans for its implementation at RAL.  
 
TUPLT143 Studies of Beam Loss Control on the ISIS Synchrotron simulation, beam-losses, synchrotron, collimation 1464
 
  • C.M. Warsop
    CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
  The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. The ISIS 800 MeV Proton Synchrotron presently provides up to 2.5·1013 protons per pulse at 50 Hz, corresponding to a mean power of 160 kW. A dual harmonic RF system upgrade is expected to increase the intensity and power by about 50%. The tighter constraints expected for higher intensity running are motivating a detailed study of beam loss distributions and the main factors affecting their control. Main aims are maximising the localisation of activation in the collector straight, and minimising risk of damage to machine components. The combination of experimental work, developments of the loss measurement systems, and simulation studies are summarised. Key factors considered include: the effects of primary collector geometry and material; the nature of the beam loss; and methods for experimentally determining spatial loss distributions.  
 
TUPLT144 Upgrade of the ISIS Main Magnet Power Supply power-supply, synchrotron, feedback, controls 1467
 
  • S. West, J.W. Gray, A. Morris
    CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
  ISIS, situated at the Rutherford Appleton Laboratory (RAL) is the world?s most powerful pulsed neutron source. At the heart of the ISIS accelerator is a proton synchrotron which uses a ring of magnets connected in series and configured as a ?White Circuit?. The magnets are connected in series with capacitor banks so that they form a resonant circuit with a fundamental frequency of 50 Hz. The circuit allows the magnets to be fed with an AC current superimposed on a DC current. The AC is currently provided by a 1MVA Motor-Alternator set and it is now proposed to replace this by a solid state UPS (Uninterruptible Power Supply) system. Tests on a smaller 80kVA unit have shown that it is possible to control the magnet current with a modified UPS system in such a way that both the frequency, phase and output voltage are under the direct influence of the control system. This paper discusses the issues surrounding the upgrading of AC supply to the main magnets with a view to improving the system reliability, improving magnet current stability and reducing the risk of mains failure.  
 
TUPLT149 Beam Manipulation and Compression Using Broadband RF Systems in the Fermilab Main Injector and Recycler emittance, booster, target, antiproton 1479
 
  • G.W. Foster, C.M. Bhat, B. Chase, J.A. Mac Lachlan, K. Seiya, P. Varghese, D. Wildman
    Fermilab, Batavia, Illinois
  Successful tests of new method for beam manipulation, compression, and stacking using the broadband RF systems in the Fermilab Recycler and Main Injector are described. Under usual conditions an unbunched beam can be confined to a fraction of the azimuth of the ring by a set of "Barrier Pulses" which repel particles trying to escape from the ends of the segment of beam. One way to compress or expand the azimuthal extent of the segment of beam is to slowly change the distance between barrier pulses. However when it is desired to rapidly compress or expand the length of the segment, a linear ramp can be superimposed on the waveform between barrier pulses. This causes particles at the front and back of the beam segment to be accelerated or decelerated by differing amounts, and the velocity correlation along the length of the beam segment causes it to expand or contract. When the expansion or contraction is halfway completed, the ramp voltage is reversed so the all particles will come relatively to rest at the end of the process. With the Barrier pulses following appropriately, no particles leak out the ends of the beam segment and the emittance is preserved.  
 
TUPLT150 Vector Sum Control of an 8 GeV Superconducting Proton Linac linac, simulation, klystron, controls 1482
 
  • M. Huening, G.W. Foster
    Fermilab, Batavia, Illinois
  Fermilab is investigating the feasibility of an economical 8 GeV superconducting linac for H-. In order to reduce the construction costs it is considered to fan out the rf power to a string of accelerating structures per klystron. Below 1 GeV the individual fluctuations of the cavities will be compensated by high power phase shifters, above 1 GeV the longitudinal dynamics are sufficiently damped to consider omitting the phaseshifters. The impact of this setup on the field stability of individual cavities and ultimately the beam energy has been studied.  
 
TUPLT168 SNS Beam Commisioning Status linac, emittance, target, beam-transport 1524
 
  • S. Henderson, A.V. Aleksandrov, S. Assadi, W. Blokland, C. Chu, S.M. Cousineau, V.V. Danilov, G.W. Dodson, J. Galambos, M. Giannella, D.-O. Jeon, S. Kim, L.V. Kravchuk, M.P. Stockli, E. Tanke, R.F. Welton, T.L. Williams
    ORNL/SNS, Oak Ridge, Tennessee
  The Spallation Neutron Source accelerator systems will provide a 1 GeV, 1.44 MW proton beam to a liquid mercury target for neutron production. The accelerator complex consists of an H- injector capable of producing 38 mA peak current, a 1 GeV linear accelerator, an accumulator ring and associated transport lines. The linear accelerator consists of a Drift Tube Linac, a Coupled-Cavity Linac and a Superconducting Linac which provide 1.5 mA average current to the accumulator ring. The staged beam commissioning of the accelerator complex is proceeding as component installation progresses. In three separate beam commissioning runs, the H- injector and Drift Tube Linac tanks 1-3 have been commissioned at ORNL. Several important performance goals have been achieved, namely 38 mA peak beam current, 1 msec beam pulse length and 1 mA average beam current. Results and status of the beam commissioning program will be presented.  
 
TUPLT179 Mini-bunched and Micro-bunched Slow Extracted Beams from the AGS extraction, simulation, resonance, kaon 1544
 
  • K.A. Brown, L. Ahrens, J.M. Brennan, J. Glenn, M. Sivertz, N. Tsoupas
    BNL, Upton, Long Island, New York
  • S.R. Koscielniak
    TRIUMF, Vancouver
  BNL's AGS has a long history of providing slow extracted proton beams to fixed target experiments. This program of providing high quality high intensity beams continues with two new experiments currently being designed for operation at the AGS; both of these new experiments require slow extracted beam, but with an added requirement of those beams experiments require slow extracted beam, but with an added requirement of those beams experiments and initial tests have been performed. In this report we will describe the beam requirements for the two experiments, and present results of detailed simulations and initial beam tests.  
 
TUPLT187 SNS Extraction Kicker Power Supply Control power-supply, kicker, extraction, controls 1568
 
  • J.-L. Mi, L. Hoff, R.F. Lambiase, Y.Y. Lee, J. Sandberg, Y. Tan, N. Tsoupas, R. Zapasek, W. Zhang
    BNL, Upton, Long Island, New York
  There are fourteen PFN power supplies, which will be installed in the SNS Extraction Kicker System. This paper will introduce these fourteen-power supplies arrangement and control schematic. These control instruments and boards are installed into four standard racks. Some of the control boards functions will be list in this paper. Control racks and some control boards pictures will be shown in this paper.  
 
TUPLT192 Transition Crossing for the BNL Super Neutrino Beam beam-losses, lattice, injection, chromatic-effects 1583
 
  • J. Wei, N. Tsoupas
    BNL, Upton, Long Island, New York
  The super neutrino beam facility proposed at the Brookhaven National Laboratory requires proton beams to cross the transition energy in the AGS to reach 1 MW beam power at top energy. High intensity beams are accelerated at a fast repetition rate. Upon transition crossing, such high intensity bunches of large momentum spreads suffer from strong nonlinear chromatic effects and self-field effects. Using theoretical and experimental methods, we determine the impact of these effects and the effectiveness of transition-jump compensation schemes, and determine the optimum crossing scenario for the super neutrino beam facility.  
 
WEOACH02 Gas Condensates onto a LHC Type Cryogenic Vacuum System Subjected to Electron Cloud vacuum, electron, synchrotron, injection 126
 
  • V. Baglin, B.J. Jenninger
    CERN, Geneva
  In the Large Hadron Collider (LHC), the gas desorbed via photon stimulated molecular desorption or electron stimulated molecular desorption will be physisorbed onto the beam screen held between 5 and 20 K. Studies of the effects of the electron cloud onto a LHC type cryogenic vacuum chamber have been performed with the cold bore experiment (COLDEX) installed in the CERN Super Proton Synchrotron (SPS). Experiments performed with gas condensates such as H2, H2O, CO and CO2 are described. Implications to the LHC design and operation are discussed.  
Video of talk
Transparencies
 
WEYCH03 Low and Medium Beta Superconducting Cavities linac, ion, heavy-ion, beam-loading 142
 
  • A. Facco
    INFN/LNL, Legnaro, Padova
  The use of low- and intermediate-beta superconducting cavities, once confined to low current heavy ion linacs, is steadily increasing in accelerators. The progress in this technology allowed a significant increase in cavity performance during the last 10 years; a large number of resonators, with different geometries, frequencies and gap numbers have been built for a large variety of applications and the development is still going on. The main boost is given by new projects of radioactive beam facilities and high power proton accelerators worldwide. While the advantages of SC resonators, compared with normal conducting structures, are rather well established in high-beta linacs, this is not always the case at low-beta. The choice of the optimum transition beam energy in a linac, where superconducting cavities should replace the room temperature ones, requires a careful evaluation that depends on the linac specifications.  
Video of talk
Transparencies
 
WEODCH01 1.5-GeV FFAG Accelerator as Injector to the BNL-AGS injection, acceleration, lattice, linac 159
 
  • A. Ruggiero, M. Blaskiewicz, T. Roser, D. Trbojevic, N. Tsoupas, W. Zhang
    BNL, Upton, Long Island, New York
  A 1.5-GeV Fixed-Field Alternating-Gradient (FFAG) Accelerator has been recently proposed as a new injector to the Alternating-Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL). It is being considered as a replacement of the present 1.5-GeV AGS Booster. The substitution will enhance the performance of the AGS accelerator facility in a variety of ways. It would still allow acceleration of all hadronic particles: protons, and heavy-ions. The major benefit is that it would considerably shorten the typical combined AGS acceleration cycle, and, consequently, may yield to an improvement of beam stability, intensity and size. The AGS-FFAG will also facilitate the proposed upgrade of the AGS facility toward a 1-MW average proton beam power. The paper describes a compact FFAG design for acceleration of protons from 200 MeV to 1.5 GeV. The circumference is about 250 m. The lattice is a periodic sequence of FDF triplets of combined-function magnets. An adjusted field profile has been calculated to compensate the variation of the main lattice functions with momentum. At injection, a beam pulse 130 μs long of negative-ions (H?) is stacked with the charge-exchange method. Acceleration of one pulse with 2.5 x 1013 protons takes about 130 μs, if harmonic-jump scheme is used in conjunction with the choice of 201.25 MHz. Four of such beam pulses are required to fill entirely the AGS. The entire filling process thus takes less than one millisecond.  
Video of talk
Transparencies
 
WEODCH02 Interaction of Stored Ions with Electron Target in Low Energy Electrostatic Ring electron, ion, target, cathode 162
 
  • E. Syresin
    JINR, Dubna, Moscow Region
  • K. Noda
    NIRS, Chiba-shi
  • T. Tanabe
    KEK, Ibaraki
  The KEK electrostatic ring is used for investigations of molecular, bimolecular and DNA ions. The electron target installed in this ring has same construction as usual electron cooler. The interaction of stored ions with the electrons increases the ion lifetime at electron cooling caused by a suppression of the ion scattering on the residual gas atoms. The proton lifetime of 2 s was increased in the experiments by factor 2 at the electron cooling with the electron beam current of 0.2 mA, the proton energy of 20 keV and the residual gas pressure of 0.04 nTorr. However the electron-ion interaction can decrease the ion lifetime caused by an excitation of the transverse instability produced by an intensive electron beam. So in the KEK electrostatic ring the proton lifetime is reduced to 1.7 s at detuning of electron acceleration voltage from nominal cooler value on 0.4 V. The simulation of electron cooling and transverse instability of the light and DNA ions are discussed in this report.  
Video of talk
Transparencies
 
WEOALH02 Multiturn Extraction Based on Trapping in Stable Islands at CERN PS: Recent Measurement Advances extraction, resonance, octupole, emittance 173
 
  • M. Giovannozzi, R. Cappi, S.G. Gilardoni, M. Martini, E. Métral, A. Sakumi, R.R. Steerenberg
    CERN, Geneva
  • A.-S. Müller
    FZK-ISS-ANKA, Karlsruhe
  Recently a novel approach to perform multi-turn extraction was proposed based on beam splitting in the transverse phase space by means of trapping inside stable islands. During the year 2002 run, preliminary measurements at the CERN Proton Synchrotron with a low-intensity, single-bunch, proton beam, confirmed the possibility of generating various beamlets starting from a single Gaussian beam. The experimental campaign continued also in the year 2003 run to assess a number of key issues, such as feasibility of trapping with high-intensity beam, capture efficiency, and multi-turn extraction proper. The experimental results are presented and discussed in detail in this paper.  
Video of talk
Transparencies
 
WEILH00 Industrial Involvement in EC Supported Accelerator R&D in the 6th Framework Programme and in Preparing Large Scale Accelerator Projects linac, electron, vacuum, klystron 194
 
  • D. Proch
    DESY, Hamburg
  The presentation will cover industrial involvement in EC supported accelerator R&D in the 6th framework programme and in preparing large scale accelerator projects (TESLA).  
Video of talk
Transparencies
 
WEPKF017 The 5 T Superconducting Undulator for the LHC Synchrotron Radiation Profile Monitor undulator, synchrotron, radiation, synchrotron-radiation 1630
 
  • R. Maccaferri, M. Facchini, R. Jung, D. Tommasini, W.  Venturini Delsolaro
    CERN, Geneva
  A Synchrotron Radiation Profile Monitor will be used in the LHC to measure the beam profiles from the injection energy of 450 GeV to the nominal energy of 7 TeV. The radiation will be provided by a sequence of two separate magnets: a two-periods 5 T superconducting undulator and the beam separation dipole D3. After a short description of the profile monitor layout, the paper reviews the electromagnetic and mechanical design of the undulator, and reports on the fabrication and cold test results of a first half period prototype.Finally, for the LHC operation with lead ion beams,a proposal for a monitor sensitivity upgrade by using a 12 T. superconducting undulator is presented and discussed.  
 
WEPKF046 Gradient Field Generation in a Uniform Gapped Magnet synchrotron, vacuum, lattice, power-supply 1705
 
  • Y. Iwashita
    Kyoto ICR, Uji, Kyoto
  • Y. Arimoto, A. Sato
    Osaka University, Osaka
  Magnets with gradient field (indexed magnets) usually have different gap distances with the different entrance positions. This situation will break a uniformity of the effective length. Trim coils, which are usually used in Cyclotron, are not practical to modify a field distribution when a large gradient is required such as FFAG. In order to generate a gradient field in a constant gapped magnet, a novel method with use of inter-pole is devised. This magnet has not only constant gap but also smaller fringing field compared with a conventional one. This technique should widen the recipe to design a magnet with such a complex magnetic field.  
 
WEPLT006 Expected Performance and Beam-based Optimization of the LHC Collimation System collimation, injection, betatron, insertion 1825
 
  • R.W. Assmann, E.B. Holzer, J.-B. Jeanneret, V. Kain, S. Redaelli, G. Robert-Demolaize, J. Wenninger
    CERN, Geneva
  The cleaning efficiency requirements in the LHC are 2-3 orders of magnitude beyond the requirements at other super-conducting circular colliders. The achievable ideal cleaning efficiency in the LHC is presented and the deteriorating effects of various physics processes and imperfections are discussed in detail for the improved LHC collimation system. The longitudinal distribution of proton losses downstream of the betatron cleaning system are evaluated with a realistic aperture model of the LHC. The results from simplified tracking studies are compared to simulations with complete physics and error models. Possibilities for beam-based optimization of collimator settings are described.  
 
WEPLT009 Dynamics of the Electron Pinch and Incoherent Tune Shift Induced by Electron Cloud electron, simulation, injection, focusing 1834
 
  • E. Benedetto, F. Zimmermann
    CERN, Geneva
  When a proton bunch passes through an electron cloud, the cloud electrons are attracted by the beam electric field; their density strongly increases near the beam centre. This gives rise to an incoherent proton tune shift, which depends on the longitudinal and radial position within the bunch. We present an analytical description of the 'electron pinch' and the resulting proton tune shift, for a circular symmetry and a Gaussian cloud. Benchmarking and extending the results by computer simulations, we explore the effects of different longitudinal beam profiles and of the nonlinear transverse force.  
 
WEPLT012 Observation of a Fast Single Bunch Transverse Instability on Protons in the SPS simulation, impedance, emittance, injection 1843
 
  • H. Burkhardt, G. Arduini, E. Benedetto, E. Métral
    CERN, Geneva
  • G. Rumolo
    GSI, Darmstadt
  The longitudinal impedance of the SPS has been reduced significantly by hardware modifications over the last years and the threshold for longitudinal instabilities increased accordingly. We now observe a fast transverse instability on high intensity single bunches of low longitudinal emittance. The main observed signature and the threshold dependence on beam parameters is described and compared with theoretical expectations and simulations.  
 
WEPLT013 Investigation of Space Charge Effects and Intrabeam Scattering for Lead Ions in the SPS space-charge, injection, scattering, emittance 1846
 
  • H. Burkhardt, D. Manglunki, M. Martini, F. Roncarolo
    CERN, Geneva
  • G. Rumolo
    GSI, Darmstadt
  Space charge effects and intrabeam scattering usually play a minor role in high energy machines like the SPS. They can potentially become a limitation for the heavy ion beams needed for the LHC at the injection plateau in the SPS. Experimental studies on space charge limitations performed on low energy proton beams in the SPS will be described. Theoretical studies have been performed to predict emittance growth times due to intrabeam scattering using several different codes.  
 
WEPLT018 Nonlinear Dynamics Studies at the CERN Proton Synchrotron: Precise Measurements of Islands Parameters for the Novel Multi-turn Extraction extraction, simulation, resonance, octupole 1861
 
  • M. Giovannozzi, P. Scaramuzzi
    CERN, Geneva
  Recently, a novel approach to perform multi-turn extraction from a circular accelerator was proposed. It is based on adiabatic capture of particles into islands of transverse phase space generated by nonlinear resonances. Sextupole and octupole magnets are used to generate these islands, while an appropriate slow variation of the linear tune allows particles to be trapped inside the islands. Intense experimental efforts showed that the approach is indeed performing rather well. However, good knowledge of the islands properties is a key ingredient for the success of this extraction type. In this paper, a series of measurements are presented dealing with the study of islands' parameters for the fourth-order resonance, such as detuning with amplitude, fixed points' position, betatron frequency, as well as detuning with amplitude inside the islands.  
 
WEPLT041 RF Amplitude Modulation to Suppress Longitudinal Coupled Bunch Instabilities in the SPS damping, synchrotron, impedance, pick-up 1924
 
  • E. Vogel, T. Bohl, U. Wehrle
    CERN, Geneva
  In the SPS, even after a considerable impedance reduction including the removal of all RF cavities used for lepton acceleration in the past, longitudinal coupled bunch instabilities develop with an LHC beam of about one fifth of the nominal bunch intensity. The nominal LHC beam is stabilised using both, the 800 MHz Landau damping cavities, in bunch shortening mode, and pre-emptive emittance blow-up. An alternative method to increase the synchrotron frequency spread and thus stabilise the beam is amplitude modulation of the accelerating RF voltage. This method might be especially suitable in accelerators without a higher harmonic RF system, as will be the case in LHC. The main results of recent studies using this method in the SPS and considerations about its use in LHC are presented.  
 
WEPLT047 A Test Suite of Space-charge Problems for Code Benchmarking simulation, space-charge, focusing, quadrupole 1942
 
  • A. Adelmann
    PSI, Villigen
  • J. Amundson, P. Spentzouris
    Fermilab, Batavia, Illinois
  • J. Qiang, R.D. Ryne
    LBNL/CBP, Berkeley, California
  A set of problems is presented for benchmarking beam dynamics codes with space charge. As examples, we show comparisons using the IMPACT, MaryLie/IMPACT, and MAD9P codes. The accuracy and convergence of the solutions as a function of solver algorithms, simulations parameters such as number of macro particles, grid size, etc. are studied.  
 
WEPLT048 Beam Dynamic Studies of the 72 MeV Beamline with a 'Super Buncher' cyclotron, simulation, space-charge, transverse-dynamics 1945
 
  • A. Adelmann, S. Adam, R. Dölling, M. Pedrozzi, J.-Y. Raguin, P. Schmelzbach
    PSI, Villigen
  A significant increase of the beam intensity increase of the PSI 590 MeV proton accelerator facility above 2 mA requires a higher accelerating voltage in the main RF cavities. A corresponding increase of the voltage in the flattop cavity would result in a complete rebuild of this device. As an alternative, a scheme with a strong buncher in the 72 MeV beam transfer line is being studied. The goal is to restore the narrow phase width (~ 2 deg/RF at 50 MHz) of the beam bunches observed at extraction from Injector 2 at injection into the Ring Cyclotron. If we can find and inject a stable particle distribution, as done in the Injector 2, the flat-top cavity might eventually be decommissioned. First results of multi particle tracking in full 6 dimensional phase space with space charge are presented.  
 
WEPLT054 Electron Cloud Build up in Coasting Beams electron, simulation, accumulation, ion 1963
 
  • G. Rumolo
    GSI, Darmstadt
  • G. Bellodi
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  • K. Ohmi
    KEK, Ibaraki
  • F. Zimmermann
    CERN, Geneva
  Electrons could in principle accumulate in the potential of coasting beams of positively charged particles until a balance between the beam force and space charge force from the electrons is reached. But the continuous interaction between a non-ideal perturbed coasting beam and the cloud of electrons being trapped by it, together with the reflection and secondary emission processes at the inner pipe wall, can alter this picture and cause a combined cloud or beam transverse instability long before the concentration of electrons reaches the theoretical equilibrium value. The issue is addressed in this paper by means of combined build-up and instability simulations carried out with the HEADTAIL code.  
 
WEPLT109 Simulation of Ep Instability for a Coasting Proton Beam in Circular Accelerators electron, vacuum, simulation, ion 2107
 
  • K. Ohmi, T. Toyama
    KEK, Ibaraki
  • G. Rumolo
    GSI, Darmstadt
  ep instability is discussed for a coasting beam operation of J-PARC 50 GeV Main Ring. Our previous study (PAC2003) was focussed only ionization electron. We now take into account electrons created at the chamber wall due to proton loss and secondary emission with higher yield than ionization.  
 
WEPLT133 On Beam Dynamics Optimization rfq, acceleration, controls, electron 2152
 
  • D.A. Ovsyannikov, S.V. Merkuryev
    St. Petersburg State University, St. Petersburg
  Mathematical optimization methods are widely used in designing and construction of charged particle accelerators. In this paper new approach to beam dynamics optimization is considered. Suggested approach to the problem is based on the analytical representation for variation of examined functionals via solutions of special partial differentional equations. The problem of optimization is considered as a problem of mutual optimization chosen synchronous particle motion and charged particles beam at whole. This approach was applied to the beam dynamics optimization for RFQ structures.  
 
WEPLT151 Using the PBO LAB(TM) Optimization and Transport Modules to Gain an Improved Understanding of the LLUMC Proton Therapy Beamlines optics, extraction, septum, beam-transport 2191
 
  • G.H. Gillespie, O.V. Voronkova
    G.H. Gillespie Associates, Inc., Del Mar, California
  • G. Coutrakon, J. Hubbard, E. Sanders
    LLU/MC, Loma Linda, California
  The Particle Beam Optics Laboratory (PBO Lab) has an advanced Optimization Module that works in concert with beam optics codes (also modules in PBO Lab) to solve optimization and fitting problems that are difficult or impossible to address with optics code alone. The PBO Lab Optimization Module has been used in conjunction with the TRANSPORT Module to study the beamlines of the proton therapy center at the Loma Linda University Medical Center (LLUMC). The primary goal of the study was to establish a fast, efficient and reliable procedure for determining the parameters of the beam extracted from the synchrotron accelerator that best fit the extensive wire scanner profile data used to monitor the LLUMC proton therapy beamlines. This paper summarizes how the PBO Lab Optimization Module is applied to this problem and presents selected results from the LLUMC proton therapy beamline study.  
 
WEPLT169 Benchmark and Threshold Analysis of Longitudinal Microwave Instability in the PSR injection, space-charge, impedance, storage-ring 2224
 
  • S.M. Cousineau, J.A. Holmes
    ORNL/SNS, Oak Ridge, Tennessee
  • C. Beltran, R.J. Macek
    LANL/LANSCE, Los Alamos, New Mexico
  A set of inductive inserts used to provide passive longitudinal space charge compensation in the Los Alamos Proton Storage Ring cause a strong microwave instability in the beam when the inductors are at room temperature. We use the ORBIT code to perform benchmarks of the microwave instability dynamics, including the mode spectrum and the instability growth time. Additionally, we analyze the experimental instability intensity threshold and compare it with the simulated threshold. For all parameters benchmarked, results of simulations are in good agreement with the experimental data.  
 
WEPLT177 Analysis of Electron Cloud at RHIC electron, injection, simulation, interaction-region 2239
 
  • U. Iriso, M. Blaskiewicz, P. Cameron, K.A. Drees, W. Fischer, H.-C. Hseuh, R. Lee, S. Peggs, L. Smart, D. Trbojevic, S.Y. Zhang
    BNL, Upton, Long Island, New York
  • G. Rumolo
    GSI, Darmstadt
  Pressure rises with high intense beams are becoming the main luminosity limitation at RHIC. Observations during the latest runs show beam induced electron multipacting as one of the causes for these pressure rises. Experimental studies are carried out at RHIC using devoted instrumentation to understand the mechanism leading to electron clouds. Possible cures using NEG coated beam pipes and solenoids are experimentally tested. In the following, we report the experimental electron cloud data and analyzed the results using computer simulation codes.  
 
WEPLT183 Clearing of Electron Cloud in SNS electron, space-charge, extraction, ion 2248
 
  • L. Wang, Y.Y. Lee, D. Raparia, J. Wei, S.Y. Zhang
    BNL, Upton, Long Island, New York
  In this paper we describe a mechanism using the clearing electrodes to remove the electron cloud in the Spallation Neutron Source (SNS) accumulator ring, where strong multipacting could happen at median clearing fields. A similar phenomenon was reported in an experimental study at Los Alamos laboratory's Proton Synchrotron Ring (PSR). We also investigated the effectiveness of the solenoid's clearing mechanism in the SNS, which differs from the short bunch case, such as in B-factories.  
 
WEPLT184 Preliminary Estimation of the Electron Cloud in RHIC electron, vacuum, simulation, dipole 2251
 
  • L. Wang, P. He, J. Wei
    BNL, Upton, Long Island, New York
  Electron cloud due to beam induce multipacting is suspected to be one of the source of pressure rises in RHIC. This paper estimates the possible electron cloud in RHIC. Various parameters related electron multipacting has been investigated.  
 
THOBCH03 Barrier RF Systems in Synchrotrons antiproton, synchrotron, emittance, hadron 236
 
  • C.M. Bhat
    Fermilab, Batavia, Illinois
  Recently, the barrier bucket techniques have been used in many interesting applications in proton synchrotrons around the world. Specially designed broad-band rf cavities are used to generate barrier buckets. At Fermilab we have barrier RF systems in four different rings and have used them for various beam gymnastics. Particularly, in the case of Fermilab Recycler Ring, all rf manipulations required during beam cooling, beam stacking and unstacking are carried out using barrier buckets. Also, we have explored new methods for increasing the beam intensities in the Main Injector. Here, I review various uses of barrier rf system in particle accelerators and possible new applications.  
Video of talk
Transparencies
 
THZCH01 Status of Tevatron Collider Run II and Novel Technologies for the Tevatron Luminosity Upgrades antiproton, electron, luminosity, emittance 239
 
  • V.D. Shiltsev
    Fermilab, Batavia, Illinois
  In the Tevatron Run-II, 36 antiproton bunches collide with 36 proton bunches at the CDF and D0 interaction regions at 980 GeV per beam. We present current status and performance of the collider complex. The plan for Run-II luminosity upgrades will be presented and novel technologies for the upgrade will be discussed.  
Video of talk
Transparencies
 
THZCH02 Electron Cooling: Remembering and Reflecting electron, ion, storage-ring, antiproton 244
 
  • I.N. Meshkov
    JINR, Dubna, Moscow Region
  The report contains a brief review of developments in electron cooling methods. The influence of electron cooling concepts on progress in particle beam physics is considered, particularly: development of alternative and complementary cooling methods - stochastic, laser, muon cooling; physics of cooled and intense particle beams; ordering effects in cooled ion beams and the idea of crystalline beams; intrabeam scattering in cooled beams, etc. Creation of new accelerator technology, based on electron cooling and its application to different fields of experimental physics, particle, nuclear and atomic physics, is described. Modern trends and new concepts of electron cooling applications are discussed.  
Video of talk
Transparencies
 
THPLT003 Vibrating Wire Scanner Parameters Optimization ion, electron, pick-up, vacuum 2460
 
  • S.G. Arutunian, K.G. Bakshetyan, N.M. Dobrovolski, M.R. Mailian, V.A. Oganessian, H.E. Soghoyan, I.E. Vasiniuk
    YerPhI, Yerevan
  • K. Wittenburg
    DESY, Hamburg
  The idea to use the metallic vibrating wire as a scanner of particles beams was experimentally confirmed [1, 2] and showed unprecedented sensibility and a huge dynamic rage of the output signal. In this work the response time of the system is estimated on the base of the dynamic model of heat transfer through the wire. A comparison of different materials of the wire is presented and the most suitable materials for different tasks are suggested. The dielectric materials are considered as possible materials of the wire, use of which allows to eliminate the electromagnetic induction from high current beams during the scanning of beam halo. The results of scanning of the iron ion beam of the mass spectrometer are presented. 1. Arutunian S.G., Avetisyan A.E., Dobrovolski N.M., Mailian M.R., Vasiniuk I.E, Wittenburg K., Reetz R., Problems of Installation of Vibrating Wire Scanners into Accelerator Vacuum Chamber. - Proc. 8-th Europ. Part. Accel. Conf. (3-7 June 2002, Paris, France), pp. 1837-1839. 2. Arutunian S.G., Dobrovolski N.M., Mailian M.R., Vasiniuk I.E., Vibrating wire scanner: first experimental results on the injector beam of Yerevan synchrotron.- Phys. Rev. Special Topics. - Accelerators and Beams, 2003, v. 6, 042801.  
 
THPLT008 A Beam Condition Monitor for the Experimental Areas of the LHC beam-losses, radiation, monitoring, luminosity 2475
 
  • L. Fernandez-Hernando, L. Fernandez-Hernando, C. Ilgner, A. Oh, H. Pernegger
    CERN, Geneva
  • A. Macpherson
    PSI, Villigen
  • T. Pritchard
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  • R. Stone
    Rutgers University, The State University of New Jersey, Piscataway, New Jersey
  The CERN Large Hadron Collider (LHC) will store 2808 bunches per colliding beam, with each bunch consisting of 1·1011 protons at an energy of 7 TeV. If there is a failure in an element of the accelerator, the resulting beam losses could cause damage not only to the machine but also to the experiments. A Beam Condition Monitor (BCM) is foreseen to monitor fast increments of fluence rate near the interaction point and, if necessary, to generate an abort signal to the LHC accelerator control to dump the beams. The system is being developed initially for the CMS experiment, but is sufficiently general to find potential applications elsewhere. Due to its high radiation hardness, CVD diamond was chosen for investigation as the BCM sensor. Various samples of CVD diamond have been characterised extensively with both a Sr-90 source and in a high intensity testbeam in order to assess the capabilities of such sensors and to study whether this detector technology is suitable for a BCM system. A selection of results from these investigations is presented.  
 
THPLT009 Comparative Transverse Distribution Measurements between the New SPS Rest Gas Ionisation Monitor and the Wire Scanner Monitors. emittance, acceleration, target, injection 2478
 
  • C. Fischer, B. Dehning, J. Koopman, D. Kramer, F. Roncarolo
    CERN, Geneva
  During the past two years, a new Ionization Profile Monitor was installed and tested in the CERN SPS. In parallel modifications were made on various wire scanner monitors. The aim is to develop instruments performing reliable measurements of transverse beam distributions in the SPS and in the LHC, in order to control the stringent emittance preservation requirements. Measurements made with the two types of monitors were performed under various conditions of LHC type beams, ranging from a pilot bunch up to beams having in the SPS nominal distributions in bunch number, intensity and energy for injection into the LHC. The data provided by the two types of instruments are compared. In the case of discrepancies, an analysis of the possible reasons is made. The cures implemented and the improvements foreseen are discussed.  
 
THPLT011 Longitudinal Loss Distribution along the LHC quadrupole, dipole, beam-losses, simulation 2484
 
  • E.B. Holzer, B. Dehning
    CERN, Geneva
  For the design and calibration of the LHC beam loss monitoring system it is essential to have good predictions of the expected longitudinal loss distributions. For this purpose a complete and detailed aperture model of one LHC sector was compiled and included with the tracking code MAD. The positions of all beam pipe bellows are included in the model as well. Therefore, it allows investigating the loss pattern due to misalignment effects, in addition to steady beam losses (beam halo, beam-beam and beam-rest gas interactions) and orbit errors. Loss maps of halo particles originating from the betatron cleaning insertion have been created for proton and ion beams. The distribution of particle losses along the beam pipe is folded with the result of GEANT simulations of the shower development through the magnets and cold masses. They link the loss of a beam particle on the aperture to particle fluencies outside of the cryostats, where the beam loss monitors will be installed. These simulations determine the positioning of the loss monitors, the longitudinal distance one detector has to cover to achieve the required resolution as well as all calibration factors for the individual detectors. The model also serves to identify hot spots, which can limit the performance of the LHC.  
 
THPLT012 Design of the Beam Loss Monitoring System for the LHC Ring beam-losses, quadrupole, collimation, monitoring 2487
 
  • E.B. Holzer, B. Dehning, E. Effinger, G. Ferioli, J.L. Gonzalez, E. Gschwendtner, G. Guaglio, M. Hodgson, V. Prieto, C. Zamantzas
    CERN, Geneva
  The beam loss monitoring (BLM) system of the LHC is one of the most critical elements for the protection of the LHC. It must prevent the super conducting magnets from quenches and the machine components from damages, caused by beam losses. It helps in the identification of the loss mechanism by measuring the loss pattern. Special detectors will be used for the setup and control of the collimators. Furthermore, it will be an important tool during machine setup and studies. The specification requirements of the BLM system include a very high reliability  
 
THPLT013 Simulation of Multi-bunch Multi-turn Instabilities in High Energy Proton Rings: Algorithms and Results simulation, impedance, target, vacuum 2490
 
  • A. Koschik
    CERN, Geneva
  A simulation code to study collective effects in multi-bunch proton machines has been developed and applied to the CERN SPS and LHC. The 3D simulation program allows the exploration of long-range effects due to resistive-wall and HOMs in circular, elliptic and rectangular vacuum chambers also for uneven filling schemes. The code has been benchmarked with measurements in the SPS. Results obtained for LHC, including beam stability and emittance growth, are presented and discussed.  
 
THPLT015 Accuracy of Profile Monitors and LHC Emittance Measurements emittance, booster, injection, acceleration 2496
 
  • F. Roncarolo, G. Arduini, B. Dehning, G. Ferioli, J. Koopman, D. Kramer
    CERN, Geneva
  The monitoring and controlling of the beam transverse emittance is essential to allow high luminosity performances in a collider operation. The profile monitors in the LHC injection chain are exploited to determine their precision. A fit strategy was developed to reduce the fitting procedure error and make it negligible compared to instrumentation errors. The method proved to be robust against non-Gaussian tails and can estimate the fraction of non-Gaussian distributed beam intensity. The procedure was applied to the 2003 SPS Wire Scanner measurements with different kind of LHC type beams. The reproducibility of the six available monitors was determined by choosing one as a reference and making synchronized measurements. Several instrumental errors were discovered and corrected to the one per cent level. The demanding small LHC transverse emittances were determined under different beam conditions in terms of intensity, bunch spacing and length in the PS Booster, PS and SPS.  
 
THPLT017 Review and Comparison of Simulation Codes Modeling Electron-Cloud Build Up and Instabilities electron, simulation, emittance, single-bunch 2502
 
  • F. Zimmermann, E. Benedetto, F. Ruggiero, D. Schulte
    CERN, Geneva
  • G. Bellodi
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  • M. Blaskiewicz, L. Wang
    BNL, Upton, Long Island, New York
  • Y. Cai, M.T.F. Pivi
    SLAC, Menlo Park, California
  • V.K. Decyk, W. Mori
    UCLA, Los Angeles, California
  • M.A. Furman
    LBNL/AFR, Berkeley, California
  • A.F. Ghalam, T. Katsouleas
    USC, Los Angeles, California
  • K. Ohmi, S.S. Win
    KEK, Ibaraki
  • G. Rumolo
    GSI, Darmstadt
  Several computer codes written at various laboratories are employed for modelling the generation and the consequences of an electron cloud. We review the most popular of these programs, which simulate either the build of an electron cloud or the instabilities it produces, and we compare simulation results for identical, or similar, input parameters obtained from the various codes.  
 
THPLT022 The Generic VME PMC Carrier Board: A Common Digital Hardware Platform for Beam Diagnostics and Feedbacks at PSI diagnostics, feedback, fibre-optics, instrumentation 2517
 
  • B. Keil, C. Buehler, P.-A. Duperrex, U. Greuter, R. Kramert, P. Pollet, V. Schlott, N. Schlumpf, P. Spuhler
    PSI, Villigen
  Rapid progress in digital electronics allows digitization of monitor signals at a very early stage of the signal processing chain, providing optimum performance and maximum flexibility for today's accelerator instrumentation. While the analog front-ends of such systems are usually specific for each monitor type, the subsequent digital part of the processing chain can be unified for many different measurement tasks. The "VME generic PMC Carrier board" (VPC) was developed to achieve this unification at the PSI electron and proton accelerator diagnostics and fast data acquisition and feedback systems. The core of the VME64x board consists of two Virtex2Pro FPGAs with two PowerPCs each, a floating point DSP and RAM. The FPGAs can acquire and process measurement data from the VMEbus P0/P2 connectors or from two application-dependent PMC mezzanine modules. Two 2 GBaud fibre optics transceivers may also be used to aquire or distribute measurement data. Envisaged applications include digital beam position (DBPM) and current monitors for proton beams, data processing for a muon decay experiment, and general beam diagnostics as well as global feedbacks at SLS accelerators and beamlines.  
 
THPLT042 Automated Orbit Control for the HERA ep Collider electron, luminosity, optics, interaction-region 2574
 
  • S.W. Herb, P.K. Bartkiewicz, F. Brinker, J.M. Maass
    DESY, Hamburg
  Successful operation of the HERA electron-proton collider requires maintaining stable orbits during the typically 12 hour luminosity runs, as well as during the fill and acceleration procedures. The primary sources of orbit errors for the electron ring are the interaction region magnets, whose support structures are integrated with the experimental detectors and susceptible to thermal and magnetic effects. The orbit correction algorithms are designed to correct these effects locally, while operating with somewhat reduced sensitivity on error sources in the rest of the ring. We describe the correction system and our operating experience.  
 
THPLT045 A more Accurate Approach to Calculating Proton Bunch Evolution under Influence of Intra-beam Scattering in a Storage Ring. scattering, synchrotron, storage-ring, background 2583
 
  • I.V. Agapov, F.J. Willeke
    DESY, Hamburg
  Some perturbations of discrete nature are known to influence the performance of a proton storage ring, contributing to parasitic background, decay of beam currents and bunch tail buildup. Such are, for example, intra-beam scattering and residual gas scattering .These processes are to a big extent described by existing analytical theory. The latter, employing a large amount of averaging, usually neglects effects arising from system nonlinearity. So, the motion of tail particles in the presence of a sufficiently nonlinear RF voltage under influence of intra-beam scattering strongly deviates from the average across the bunch and the analytical approach seems inadequate for it. To overcome this situation we have developed more accurate numerical methods for calculations of bunch evolution under influence of a rather broad class of jump-like perturbations. Here we present the computational algorithms and their application to assessment of coasting beam and proton background in HERA-p.  
 
THPLT047 Beam Position Monitor Development for the IThemba LABS Cyclotron Beamlines cyclotron, vacuum, diagnostics, alignment 2589
 
  • J. Dietrich, I. Mohos
    FZJ/IKP, Jülich
  • A.H. Botha, J.L. Conradie, J.L.G. Delsink, P.F. Rohwer
    IThemba Labs, Somerset West
  In cooperation of iThemba LABS (South Africa) and Forschungszentrum Juelich the specification of a sensitive tunable rf narrowband beam position monitor system for cyclotron beamlines has been elaborated. iThemba LABS developed and manufactured the four section stripline monitor chamber. The monitor electronics were developed in the Forschungszentrum Juelich-IKP. The electronics consisting of an RF signal processing module (BPM-RF) and a data acquisition and control module (BPM-DAQ) sequentially processes and measures the monitor signals and deliver via serial network calculated horizontal and vertical beam position data. First measurements with cyclotron beam has been performed in the iThemba LABS in November 2003. Changed beam position due to changing different cyclotron parameters could be studied with high accuracy. The resolution of the beam position measurement was better than 0.1 mm with beam currents down to 0.0005 mA.  
 
THPLT060 An Automatic Beam Characterization Instrument for Proton Therapy Applications radiation, monitoring, background, diagnostics 2625
 
  • D. Giove, C. De Martinis, M. Mauri
    INFN/LASA, Segrate (MI)
  • C. Cirrone, G. Cuttone
    INFN/LNS, Catania
  The characterization in the transverse plane of the beam is a fundamental step in the design of a proton therapy facility. In this paper we will describe an automatic system able to measure the transverse profiles of the proton beam used in the Catana facility at LNS-Catania. The system has been designed as an autonomous equipment able to acquire optical images of the beam (after an interaction with a converter) and to elaborate them to extract the relevant parameters. The equipment may be interfaced to the rest of the control system of the facility and to the operator interface to provide high level control and monitoring tools. Operational experience will be discussed and the results so far obtained will be outlined.  
 
THPLT072 Magnet and RF Systems of Small Pulse Synchrotron for Radiotherapy dipole, quadrupole, synchrotron, sextupole 2661
 
  • K. Endo, K. Egawa, Z. Fang, S. Yamanaka
    KEK, Ibaraki
  To cure the malignant tumor it is desirable to equalize the treatment level to everybody anywhere he lives in. Proton and/or carbon-ion therapy are now considered as a powerful remedy as the radiation dose can be easily concentrated to the target volume by utilizing the Bragg?s peak. If a small medical accelerator is developed at a reasonable cost, it has a big potential to promote the advanced medical treatment with the accelerator in every place. This pulse synchrotron aims to reduce the size of the accelerator by generating the high magnetic field in a short time which leads to a compact ring of high field magnets. Acceleration time is only 5 msec by using the discharge current of a capacitor bank as large as 200 kA at peak, almost equivalent to half sinusoidal 50 Hz. Part of the discharge current is branched to excite the quadrupole magnets to assure the tracking between the dipole and quadrupole fields. Pulsed power technique is also adopted to drive the RF power tubes. Both magnet and RF systems have been developed and being extensively studied. Technological sides of both systems will be treated in details as well as the computational beam behaviors in this pulse synchrotron.  
 
THPLT078 Construction of FFAG Accelerators in KURRI for ADS Study acceleration, booster, ion, ion-source 2676
 
  • M. Tanigaki, K. Mishima, S. Shiroya
    KURRI, Osaka
  • S. Fukumoto, Y. Ishi
    Mitsubishi Electric Corp, Energy & Public Infrastructure Systems Center, Kobe
  • M. Inoue
    SLLS, Shiga
  • S. Machida, Y. Mori
    KEK, Ibaraki
  KART (Kumatori Accelerator driven Reactor Test) project has started at Kyoto University Research Reactor Institute (KURRI) from the fiscal year of 2002. The purpose of this project is to demonstrate the basic feasibility of ADS, studying the effect of incident neutron energy on the effective multiplication factor of the subcritical nuclear fuel system. We are now constructing a proton FFAG accelerator complex as a neutron production driver for this project. Our accelerator complex consists of a 2.5 MeV FFAG betatron as an injector and 20 MeV and 150 MeV FFAG synchrotrons as a booster and a main ring, respectively. Our FFAG betatron is a spiral sector type. Both booster and main rings are radial sector type FFAG synchrotrons, but different in the production of required magnetic field with a certain magnetic field index. The distribution of magnetic field is determined by the shaped pole-face in the main ring while the magnetic field is realized by use of trim coils in the booster ring. This FFAG complex will be combined with our Kyoto University Critical Assembly (KUCA) in KURRI by the end of March 2006 and the experiments will begin as soon as the whole system is ready.  
 
THPLT079 The Study of APF-IH Linac linac, ion, focusing, acceleration 2679
 
  • K. Yamamoto, T. Hattori, K. Yamamoto
    RLNR, Tokyo
  • M. Okamura
    RIKEN, Saitama
  • S. Yamada
    NIRS, Chiba-shi
  We have manufactured the IH linac with Alternating Phase Focus as the test machine of medical accelerator injection. It will accelerate C4+ ion up to 2MeV/u from 40 keV/u, the tank length is around 1.5m, operation frequency is 100MHz. Furthermore, We have succeeded the acceleration test using proton with simple acceleration system consist of P.I.G. ion source, bending magnets and focus lenses, less than 5m long. Otherwise, We have been making the program of beam dynamics with the results of the electro-magnetic simulation soft (Micro-Wave-Studio,OPERA-3D), it has the merit of easily to calculate the 3D- beam dynamics in the tank. We will report the some results of the test and the beam simulation and the comparisons.  
 
THPLT111 An Accelerator-based Thermal Neutron Source for BNCT Application target, electron, rfq, beam-loading 2745
 
  • A. Makhankov, A. Gervash, R. Giniyatulin, I. Mazul, M. Rumyantsev
    NIIEFA, St. Petersburg
  • J. Esposito, L.B. Tecchio
    INFN/LNL, Legnaro, Padova
  • V. Khripunov
    RRC Kurchatov Institute, Moscow
  An accelerator-based thermal neutron source, aimed at the BNCT treatment of skin melanoma is in construction at the INFN-LNL in the framework of SPES project. The BNCT device exploit the intense proton beam provided by a 5 MeV, 30 mA RFQ that represent the first accelerating step of the SPES exotic nuclei production beam facility. Neutrons are generated by 9Be(p,n)9B nuclear reaction in a high power (150 kW) Beryllium target. The operational condition of the Beryllium converter is close to the condition of Be-armoured components in fusion reactors. The main difference consists in the necessity of limitation of structural materials amount used in the design in order to meet therapeutic irradiation requirements. Two possible design of neutron converter are developed: one with saddle block tiles brazed to CuCrZr tubes and another one with Be target made from solid Be block. Results of R&D works on the development of water cooled Be target for converter are presented, including data on selected materials, technological trials and mockups high heat flux testing.  
 
THPLT114 A New Mono-energetic Neutron Beam Facility in the 20-180 MeV Range target, ion, light-ion, background 2753
 
  • V.G. Ziemann, L.-O. Andersson, T. Bergmark, O. Bystrom, A. Bäcklund, H. Calen, L. Einarsson, C. Ekström, J. Fransson, K.J. Gajewski, N. Haag, T. Hartman, E. Hellbeck, T. Johansen, O. Jonsson, B. Lundström, R.P. Peterson, L. Pettersson, A. Prokofiev, D. Reistad, P.-U. Renberg, R. Wedberg, D. Wessman, L. Westerberg, D. van Rooyen
    TSL, Uppsala
  • J. Blomgren, S. Pomp, U. Tippawan, M. Österlund
    INF, Uppsala
  Recent interest in nuclear applications involving neutrons, like ransmutation of nuclear waste, fast-neutron cancer therapy, dose to personnel in aviation and electronics failures due to cosmic-ray neutrons, motivate the development of a facility producing intense mono-energetic neutron beams. At The Svedberg laboratory (TSL), Uppsala, Sweden, we have developed such a facility by utilizing the existing cyclotron and inserting a flexible Lithium target in a rebuilt beam line. The new facility can operate at unsurpassed quasi-monoenergetic neutron intensities and provides large flexibility of the neutron beam properties, like diameter and shape.  
 
THPLT129 Ion Chambers for Monitoring the NuMI Beam at FNAL target, hadron, ion, instrumentation 2768
 
  • S.E. Kopp, D. Indurthy, R. Keisler, S. Mendoza, Z. Pavlovich, M. Proga, R.M. Zwaska
    The University of Texas at Austin, Austin, Texas
  • M. Diwan, B. Viren
    BNL, Upton, Long Island, New York
  • A.R. Erwin, H.P. Ping, C.V. Velisaris
    UW-Madison/PD, Madison
  • D. Harris, A. Marchionni, J. Morfin
    Fermilab, Batavia, Illinois
  • J. McDonald, D. Naples, D. Northacker
    University of Pittsburgh, Pittsburgh, Pennsylvania
  We summarize selected instrumentation under construction for the NuMI neutrino beam facility at Fermilab. An array of foil secondary emission monitors (SEM's) will measure the 120GeV proton beam position, profile and halo at 10 stations along the transport to the NuMI target. The final two foil SEM's align the proton beam to within 50 microns on target. These are capable of withstanding the 400kW proton beam and causing <5·10-6 beam loss. Further instrumentation includes four stations of ionization chambers located downstream of the decay volume, one upstream and three downstream of the beam dump. The latter three monitor the tertiary muon beam, the first monitors the remnant hadron beam. The ion chamber arrays align the proton beam to 14microRadian and the neutrino beam to within 50 microRadian, as well as monitoring flux to better than 1%. The ion chambers are designed to withstand the ~1GRad doses and 109 particle/cm2/spill fluxes anticipated during NuMI beam operations. Beam tests and R&D efforts are discussed.  
 
THPLT130 Synchronization of the Fermilab Booster and Main Injector for Multiple Batch Injection booster, feedback, injection, extraction 2771
 
  • R.M. Zwaska, S.E. Kopp
    The University of Texas at Austin, Austin, Texas
  • W. Pellico, R.C. Webber
    Fermilab, Batavia, Illinois
  To date, the 120 GeV Fermilab Main Injector accelerator has accelerated a single batch of protons from the 8 GeV rapid-cycling Booster synchrotron for production of antiprotons for Run II. In the future, the Main Injector must accelerate 6 or more Booster batches simultaneously; the first will be extracted to the antiproton source, while the remaining are extracted for the NuMI/MINOS neutrino experiment. Performing this multi-batch operation while avoiding unacceptable radioactivation of the beamlines requires a previously unnecessary synchronization between the accelerators. We describe a mechanism and present results of advancing or retarding the longitudinal progress of the Booster beam by active feedback radial manipulation of the beam during the acceleration period.  
 
THPLT133 Simulation of RF Control of a Superconducting Linac for Relativistic Particles linac, simulation, feedback, beam-loading 2774
 
  • M. Huening, P. Bauer, G.W. Foster
    Fermilab, Batavia, Illinois
  We present a code to simulate the rf field and field control in a superconducting linac for relativistic heavy particles. In such a linac the field stability is strongly influenced by the longitudinal beam dynamics. So the code has to simulate both the field and the beam dynamics with the resulting varying beam loading. Other effects included in the simulation are Microphonics and Lorentz force. The code can simulate both single cavity and vector sum control.  
 
THPLT135 Experience with the 1.7 GHz Schottky Pick-ups in the Tevatron pick-up, antiproton, emittance, betatron 2777
 
  • A. Jansson, P. Lebrun, R. Pasquinelli
    Fermilab, Batavia, Illinois
  During a 2003 shutdown, new high-frequency Schottky pick-ups were installed in the Tevatron. These devices operate at 1.7 GHz (harmonic ~36000 of the revolution frequency) and can in principle be used to measure tunes, chromaticities, momentum spread and transverse emittances of individual bunches. Only the transverse signal is used, as the longitudinal is dominated by coherent signal. The default mode of operation during a store is to sequentially acquire and analyze frequency data from different sets of bunches in the machine. This function is performed by an open access client written in Java/C++, running in the background. The resulting fit parameters are datalogged and can also be plotted in "real time" during the store. With an alternative setup, data from select bunches can be acquired continuously during the entire ramp (and squeeze), for analysis off-line. This paper describes the evolution, current status and performance of the acquisition and analysis software, and presents measurements with comparison to predictions and other measurement techniques. One example of such a measurement is the variation of beam-beam tune shift as a function of intensity and bunch position within a train.  
 
THPLT137 Commissioning of the Head-tail Monitoring Application for the Tevatron synchrotron, kicker, acceleration, monitoring 2780
 
  • V.H. Ranjbar, V. Lebedev, E. Lorman, A. Xiao
    Fermilab, Batavia, Illinois
  A head-tail beam monitoring application has recently been developed for use in the Tevatron. With this application beam dynamics problems including head-tail instabilities can be monitored. In addition it can be use to perform chromaticity measurements using the head-tail technique developed at CERN. This application speeds up chromaticity measurements in the Tevatron especially during the acceleration ramp and low beta squeeze, which previously required three separate ramps using uncoalesced protons  
 
THPLT171 Stochastic Cooling Studies in RHIC, II kicker, scattering, pick-up, feedback 2861
 
  • M. Blaskiewicz, J.M. Brennan, J. Wei
    BNL, Upton, Long Island, New York
  Intra-beam scattering is unavoidable for highly charged heavy ions and causes emittance growth during the store for collision physics. A longitudinal bunched beam stochastic cooling system will confine the bunch within the RF bucket increasing the useful luminosity. A single bunch, Palmer cooling system is under investigation. We present data and compare them with theory.  
 
THPLT172 Self-adaptive Feed Forward Scheme for the SNS Ring RF System target, simulation, extraction, accumulation 2864
 
  • M. Blaskiewicz, K. Smith
    BNL, Upton, Long Island, New York
  During one millisecond of injection stacking, the RF beam current varies from 0 to 50 Amperes. The control loops of the RF system are operative throughout this process. Acceptable setpoints will be found during commissioning, but as vacuum tubes age and beam currents increase these setpoints will become less optimal. A scheme by which the system can optimize itself is presented.  
 
THPLT173 RHIC BPM Performance: Comparison of Run 2003 and 2004 background, instrumentation, pick-up, quadrupole 2867
 
  • R. Calaga, R. Tomas
    BNL, Upton, Long Island, New York
  Identification of malfunctioning BPMs plays an important role in any orbit or turn-by-turn analysis. Singular value decomposition (SVD)and Fourier transform methods were recently employed to identify malfunctioning BPMs at RHIC. A detailed statistical comparison between the two methods for Run 2003 was in good agreement and proved to be a robust method to identify faulty BPMs. We evaluate detailed BPM performance for different versions of BPM low-level software in 2003 and 2004.  
 
THPLT177 Maps for Fast Electron Cloud Simulations at RHIC electron, simulation, luminosity, space-charge 2870
 
  • U. Iriso, S. Peggs
    BNL, Upton, Long Island, New York
  Luminosity in several colliders, including RHIC, is limited by the electron cloud effect. A careful re-distribution of the bunch pattern around the azimuth of a ring can decrease the average electron density for a fixed total bunch current, allowing the luminosity to be increased. In the search for a bunch pattern that maximizes the luminosity, a fast computer simulation is a key requirement. We discuss the use of fast polynomial maps to simulate the bunch to bunch evolution of the electron density at RHIC. Such maps are empirically derived from existing conventional slow simulation codes.  
 
FRXCH01 Development of High Power Targets target, radiation, injection, recirculation 276
 
  • G.S. Bauer
    FZJ/ESS, Jülich
  High power targets are at the very heart of most applications of accelerators to science and technology. With many projects aiming to utilize beams in the multi-megawatt power range, solid targets, in particular stationary ones, become increasingly difficult. Liquid metal targets have become the concept of choice. Designs cover a variety of concepts ranging from free jets to allow extraction of low energy ? highly ionizing radiation (pions and muons) to fully enclosed systems if neutron generation is the main goal. Mercury is often the preferred target material due to its liquid state at room temperature and other favourable properties. Designs aiming at high temperature operation depending on small neutron absorption rely on PbBi as target material. Liquid lithium is proposed for a deuteron stripping target for the IFMIF project. Questions that need to be solved include solid-liquid metal reactions, radiation effects, general liquid metal technology, handling of spallation products as well as design of components and subsystems. In addition, short pulse operation leads to the generation of pressure waves inside the targets and the need to control their consequences.  
Video of talk
Transparencies
 
FRXBCH01 Novel Ideas and R&D for High Intensity Neutrino Beams target, factory, electron, storage-ring 281
 
  • K.J. Peach
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  Recent developments in neutrino physics, primarily the conclusive demonstration of neutrino oscillations in both atmospheric neutrinos and solar neutrinos, provide the first conclusive evidence for physics beyond the Standard Model of particle physics. The phenomenology of neutrino oscillations, for three generations of neutrino, requires six parameters - two squared mass differences, 3 mixing angles and a complex phase that could, if not 0 or pi, contribute to the otherwise unexplained baryon asymmetry observed in the Universe. Exploring the neutrino sector will requires very intense beams of neutrinos, and needs novel solutions.  
Video of talk
Transparencies