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injection

                              
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MOPKF006 Enhancements of Top-up Operation at the Swiss Light Source storage-ring, linac, controls, booster 309
 
  • B. Kalantari, T. Korhonen, A. Lüdeke, C. Quitmann
    PSI, Villigen
  Since the first experience on 2001, Top-Up is the standard mode of operation at the Swiss Light Source (SLS) for users. In order to fulfill the ongoing demands of machine experts and experiments we have had to add more functionality to the Top-Up mode thus make it more flexible. Some time-resolved experiments require a constant charge in a single isolated bucket in the gap of the normal filling of a bunch train of 80% of the circumference of the storage ring. Therefore the Hybrid application was developed that keeps the beam current distribution constant in this mode. We developed a maintenance mode too, to allow to work continuously on the Linac and booster - for example to optimize injection/extraction - without disturbing the Top-up for user operation. Even beam destructive experiments at the Linac during Top-Up or Hybrid operation are supported, where the Linac can be used synchronously at the times between successive refilling of the storage ring. The flexible control and timing systems at the SLS made these applications feasible. We describe the controls, operation and applications of each of the above functionalities in this paper.  
 
MOPKF033 Operational Improvements in the ESRF Injection Complex booster, emittance, linac, quadrupole 375
 
  • Y. Papaphilippou, P. Elleaume, L. Farvacque, L. Hardy, G.A. Naylor, E. Plouviez, J.-L. Revol, B.K. Scheidt, V. Serriere
    ESRF, Grenoble
  The ESRF injection complex, comprising a 200MeV linac, a booster accelerator with a top energy of 6GeV and two transfer lines, has been routinely injecting beam to the storage ring since the beginning of its operation. The newly implemented injection with ‘‘front-end open'' triggered several operational improvements in order to maximise the reliability of the complex. A series of diagnostics (sychnotron light monitors, striplines, fast current transformers) were implemented allowing the measurement and monitoring of several components of the injected beam. New optics models were constructed and several application systems as the closed orbit correction or tune measurements have been upgraded. The operational procedures of injection at 100MeV in the booster and the injection efficiency maximisation were renewed and improved. Further developments for the uninterrupted operation of the storage ring during injection, such as the bunch cleaning in the booster were successfully tested.  
 
MOPKF047 Suppression of Stored Beam Oscillation Excited by Beam Injection sextupole, storage-ring, synchrotron, optics 414
 
  • T. Ohshima, N. Kumagai, M. Masaki, S. Matsui, H. Ohkuma, K. Soutome, M. Takao, H. Tanaka
    JASRI/SPring-8, Hyogo
  Top-up operation is scheduled from May 2004 at SPring-8. For this operation it is important that frequent beam injections should not excite the oscillation of stored beams. However, injection bump orbit was not closed perfectly and residual beam oscillations lead to increase of effective beam sizes by twice and three times in the horizontal and vertical direction respectively. We are trying to reduce these excited oscillations to less than one third of the usual beam sizes. For the suppression of horizontal one, we applied a novel scheme to reduce the effect due to the nonlinearity of sextupole magnets by adjusting the strength ratio of the sextupoles. The field similarity of bump magnets was also improved by replacing them with newly designed ones, where the effect of eddy current at the end plates was reduced. These countermeasures suppressed the horizontal oscillation by about one order. For the suppression of vertical one, the excitation mechanism has being investigated in detail. Presently the tilt angle adjustment of bump magnets reduced the vertical oscillation by one third. For further reduction of these oscillations, corrections with pulse-magnets is under investigation.  
 
MOPKF048 Injection Beam Loss at the SPring-8 Storage Ring undulator, storage-ring, betatron, simulation 417
 
  • M. Takao, T. Ohshima, S. Sasaki, J. Schimizu, K. Soutome, H. Tanaka
    JASRI/SPring-8, Hyogo
  Capture efficiency of injection beam is extremely important for top-up operation because open photon shutter permits the bremsstrahlung from lost particles to be transported to experimental floor. Furthermore, since the SPring-8 storage ring has many in-vacuum insertion devices with narrow gap, the demagnetization by the lost electron bombardment is also serious to the beam injection with gap closing. To clarify the loss mechanism of injected beam at the SPring-8 storage ring, we investigate the loss process under various conditions of the storage ring, and especially measure the dependence of injection loss rate on gaps of insertion devices. Comparing the measurements with simulations, we found that an injected particle with a large horizontal amplitude begins to oscillate in vertical direction through error magnetic field and eventually disappears at the vertical limit. It is also found that the low chromaticity of the storage ring is effective for the reduction of injection beam loss. In this paper, we report the loss mechanism of the injection beam of the SPring-8 storage ring and the possible improvements of the capture efficiency.  
 
MOPKF059 Magnet Specification for the Daresbury Laboratory Energy Recovery Linac Prototype dipole, quadrupole, linac, booster 443
 
  • N. Thompson, N. Marks
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  Daresbury Laboratory has funding for the design and construction of an Energy Recovery Linac (ERL) prototype to facilitate the R&D necessary for the 4th Generation Light Source (4GLS). In the prototype a 35MeV electron beam will be used to drive an Infra-Red Oscillator Free-Electron Laser. The ring consists of two 180°; triple bend achromats, two straight sections, an injection chicane, an extraction chicane and two bunch compression/decompression chicanes. A number of pre-existing magnets will be used in the ring so the new magnets have been designed to ensure compatibility with the existing designs, enabling common power supply, vacuum and control system specifications. This paper gives an overview of the magnet requirements for the facility and details of the engineering realisation.  
 
MOPKF061 Optics Layout for the ERL Prototype at Daresbury Laboratory linac, electron, extraction, beam-transport 449
 
  • B.D. Muratori, H.L. Owen, J.A. Varley
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  The overall optics for the Energy Recovery Linac Prototype (ERLP) at Daresbury Laboratory is summarised. This includes the layout of the injector line, all chicanes used, as well as details of both the outward and return TBA arcs. The tunability in several sections of the machine is examined under different operational modes and starting parameters from the end of the booster to the dump.  
 
MOPKF087 The Cebaf Energy Recovery Experiment: Update and Future Plans linac, emittance, optics, diagnostics 524
 
  • A. Freyberger, K. Beard, S.A. Bogacz, Y.-C. Chao, S. Chattopadhyay, D. Douglas, A. Hutton, L. Merminga, C. Tennant, M. Tiefenback
    Jefferson Lab, Newport News, Virginia
  A successful GeV scale energy recovery demonstration with a high ratio of peak-to-injection energies (50:1) was carried out on the CEBAF (Continuous Electron Beam Accelerator Facility) recirculating superconducting linear accelerator in the spring 2003. To gain a quantitative understanding of the beam behavior through the machine, data was taken to characterize the 6D phase space during the CEBAF-ER (CEBAF with Energy Recovery) experimental run. The transverse emittance and energy spread of the accelerating and energy recovered beams were measured in several locations to ascertain the beam quality preservation during energy recovery. Measurements also included the RF system's response to the energy recovery process and transverse beam profile of the energy recovered beam. One of the salient conclusions from the experiment is that the energy recovery process does not contribute significantly to the emittance degradation. The current status of the data analysis will be presented as well as plans for a GeV scale energy recovery experimental run with current doubling.  
 
MOPLT001 Acceleration of Electrons by Spatially Modulated Laser Wave electron, acceleration, laser, vacuum 527
 
  • R.A. Melikian, M.L. Petrosyan, V.S. Pogosyan
    YerPhI, Yerevan
  We study the acceleration of electrons in a system of linearly polarized laser wave, propagating at small angles to the direction of electron motion. The parameters of electron bunch and laser wave are chosen so, that during driving electrons in a band of a wave, the electric field of a wave has not changed the direction. The requirements of deriving of maximum rate of acceleration are found depending on parameters of electronic bunch and laser wave. It is shown, that the dependence of growth of electrons energy from number of light bands has nonlinear character. The influence of light diffraction on process of acceleration is considered. It is shown, that the discussed scheme of acceleration allows a possibility of deriving of high acceleration rate owing to existence of modern powerful lasers.  
 
MOPLT007 Base Line Design for a Beta-beam Neutrino Facility ion, acceleration, linac, target 542
 
  • M. Benedikt, S. Hancock, M. Lindroos
    CERN, Geneva
  The term beta-beam has been coined for the production of pure beams of electron neutrinos or their antiparticles through the decay of radioactive ions circulating in a storage ring. The neutrino source itself consists of a high energy storage ring (gamma ~150), with long straight sections in line with the experiment(s). The radioactive ions (6He and 18Ne) will be produced in an ISOL type target system. Due to the short life times of around 1s at rest, the beam needs to be accelerated as quickly as possible. For this a staged system of accelerators is proposed. The chain starts with a linac followed by a rapid cycling synchrotron for acceleration up to ~300 MeV/u. For further acceleration the existing PS and SPS machines are used. Finally, after acceleration to SPS top energy, the ions are transferred to the decay ring where they are merged with the already circulating bunch through a longitudinal stacking procedure. The base line design of the beta beam facility will be presented and the major design problems encountered as well possible solutions will be discussed.  
 
MOPLT012 Collimation in the Transfer Lines to the LHC collimation, simulation, proton, 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.  
 
MOPLT014 Testing of the LHC Magnets in Cryogenic Conditions: Current Experience and Near Future Outlook dipole, multipole, instrumentation, sextupole 560
 
  • V. Chohan, M. Buzio, G. De Rijk, J. Miles, P. Pugnat, V. Remondino, S. Sanfilippo, A.D. Siemko, N. Smirnov, B. Vullierme, L. Walckiers
    CERN, Geneva
  For the Large Hadron Collider under construction at CERN, a necessary and primordial condition prior to its installation is that all the main twin-aperture Dipole and Quadrupole magnets are tested in the 1.9K cryogenic conditions. These tests are not feasible at the manufacturers and hence, are carried out at CERN at a purpose built facility on the site. This presentation will give an overall view of the issues related to the operation of the tests facility. In particular, it will give the goals that need to be met to ensure the magnet integrity and performance and the context & constraints on the test programme. Results accumulated from the tested magnets and the ensuing tests stream-lining will be presented, together with some of the explanations and hard limits. Finally, some improvements planned for efficient operation will be given within the confines of the testing programme as was foreseen and the project goals and deadlines.  
 
MOPLT018 Aperture and Delivery Precision of the LHC Injection System extraction, vacuum, quadrupole, kicker 572
 
  • B. Goddard, M. Gyr, J.-B. Jeanneret, V. Kain, M. Lamont, V. Maire, V. Mertens, J. Wenninger
    CERN, Geneva
  The main LHC injection elements in interaction regions 2 and 8 comprise the injection septa (MSI), the injection kicker (MKI), together with three families of passive protection devices (TDI, TCDD and TCLI). The apertures of the injection septa for the injected and two circulating beams are detailed with a new enlarged vacuum chamber and final septum alignment. The circulating beam aperture of the TDI is detailed with a new TDI support design and modified vacuum tank alignment. A modified TCDD shape is also presented and the implications for the aperture and protection level discussed. The various errors in the SPS, the transfer lines and the injection system, which contribute to injection errors, are analysed, and the expected performance of the system is derived, in terms of the expected delivery precision of the injected beam.  
 
MOPLT019 Experience Gained in the SPS for the Future LHC Abort Gap Cleaning betatron, feedback, optics, proton 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 proton, emittance, scattering, 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 simulation, kicker, proton, 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.  
 
MOPLT025 Status and Plans for the SPS to LHC Beam Transfer Lines TI 2 and TI 8 optics, extraction, alignment, quadrupole 593
 
  • V. Mertens, B. Goddard, T. Risselada
    CERN, Geneva
  Beam transfer from the CERN Super Proton Synchrotron (SPS) to the Large Hadron Collider (LHC) will be done through the two transfer lines TI 2 and TI 8, presently under construction, with a combined length of about 5.6 km. The final layout, optics design and correction scheme for these lines will be presented. The requirement of simultaneously matching their geometry and optics with that of the LHC will be treated, including the methodology for alignment of the elements along the line and a proposed solution in the final matching section. After the commissioning of the short transfer line TT40 just upstream of TI 8 in 2003, beam tests of the whole of TI 8 are scheduled for autumn 2004, with the aim to validate many of the new features and mechanisms involved in the future control and operation of these lines. The status of the installation will be described, comprising the progress with infrastructure, services and line elements. An outlook will be given for the work remaining until 2007.  
 
MOPLT031 LHC Abort Gap Filling by Proton Beam collimation, radiation, proton, 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.  
 
MOPLT034 Possible Causes and Consequences of Serious Failures of the LHC Machine Protection System dumping, extraction, kicker, quadrupole 620
 
  • J.A. Uythoven, R. Filippini, B. Goddard, M. Gyr, V. Kain, R. Schmidt, J. Wenninger
    CERN, Geneva
  The LHC machine protection systems, including the beam dumping system, are designed to ensure that failures leading to serious damage to the LHC during its lifetime are extremely unlikely. These kind of failures have to date been considered as being ?beyond the design case?, for instance requiring a combination of equipment failure and surveillance failure. However, they need to be evaluated to determine the required safety levels of the protection systems. A second objective is to understand if measures can and should be taken to further reduce the probability of such failures, or to minimise their impact. This paper considers various serious failure modes of the different machine protection systems. The probable consequences and possible ameliorating measures of the worst-case scenarios are discussed. The particular case of having a stored beam with an unavailable beam dumping system is mentioned, together with possible actions to be taken in such an event.  
 
MOPLT035 Beam Induced Heating of the SPS Fast Pulsed Magnets impedance, kicker, extraction, vacuum 623
 
  • J.A. Uythoven, G. Arduini, T. Bohl, F. Caspers, E.H.R. Gaxiola, T. Kroyer, M. Timmins, L. Vos
    CERN, Geneva
  Fast pulsed magnets with ferrite yokes are used in CERN?s SPS accelerator for beam injection, extraction and excitation for tune measurements. The impedance of the ferrite structures can provoke significant beam induced heating, especially for beams with high peak currents as for LHC operation, even beyond the Curie temperature. The expected heating in the different kicker systems for various operational modes is compared with beam measurements. Estimates of the beam induced power have been derived from measured beam spectra. A fast extraction kicker system has recently been equipped with a cooling system. The measured cooling performance is compared with data from laboratory setups and numerical simulations.  
 
MOPLT049 A Very High-beta Optics to be used for an Absolute Luminosity Determination with Forward Detectors in ATLAS optics, scattering, luminosity, emittance 659
 
  • A. Faus-Golfe
    IFIC, Valencia
  • I. Efthymiopoulos, P. Grafstrom, M. Rijssenbeek
    CERN, Geneva
  • M. Haguenauer
    Ecole Polytechnique, Palaiseau
  Atlas detector at the LHC pursues a number of different approaches to obtain an estimate of the absolute luminosity. Measuring elastic scattering at very small angles (3 mu rad) represents a different and complimentary approach that will improve the precision of the final luminosity estimate. In this paper we show the required very hihg-beta optics, detector acceptance studies, and running conditions and calculated performance for the proposed forward detectors located near the ATLAS interaction region.  
 
MOPLT062 The Design of a Prototype RF Compressor for High Brightness Electron Beams electron, bunching, RF-structure, extraction 698
 
  • D. Giove, F. Alessandria, A. Bacci, C. De Martinis, M. Mauri
    INFN/LASA, Segrate (MI)
  • D. Alesini, M. Ferrario, A. Gallo, F. Marcellini
    INFN/LNF, Frascati (Roma)
  • L. Serafini
    INFN-Milano, Milano
  The generation of sub-ps electron bunches with low transverse emittance at nC charge level is a crucial requirement in the design of injectors for short wavelength FEL's. The technique of velocity bunching has been by now experimentally proven in various laboratories, where bunches below the ps bunch length were obtained: however, preservation of a low transverse emittance after the bunch compression is still to be demonstrated. To this aim, the use a slow wave RF structure as a rectilinear compressor has been proposed in the past to overcome the inherent difficulties of magnetic compressors. In this paper we will review the work carried out in the last 2 years and focused on the design a RF compressor based on a 3 GHz slow-wave copper structure. The rationale of the conceptual design along with a description of the main experimental activities will be presented and the future application of such a scheme to the SPARC project will be discussed.  
 
MOPLT067 KEKB Performance luminosity, vacuum, electron, positron 707
 
  • Y. Funakoshi, K. Akai, K. Ebihara, K. Egawa, A. Enomoto, J. Flanagan, H. Fukuma, K.  Furukawa, T. Furuya, J. Haba, S. Hiramatsu, T. Ieiri, N. Iida, H. Ikeda, T. Kageyama, S. Kamada, T. Kamitani, S. Kato, M. Kikuchi, E. Kikutani, H. Koiso, M. Masuzawa, T. Mimashi, A. Morita, T. Nakamura, H. Nakayama, Y. Ogawa, K. Ohmi, Y. Ohnishi, N. Ohuchi, K. Oide, M. Shimada, S. Stanic, M. Suetake, Y. Suetsugu, T. Sugimura, T. Suwada, M. Tawada, M. Tejima, M. Tobiyama, S. Uehara, S. Uno, S.S. Win, N. Yamamoto, Y. Yamamoto, Y. Yano, K. Yokoyama, M. Yoshida, M. Yoshida, S.I. Yoshimoto
    KEK, Ibaraki
  • F. Zimmermann
    CERN, Geneva
  The KEKB B-Factory is an electron-positron double ring collider working at KEK. Its peak luminosity surpassed 1034 /cm2/sec in May 2003 for the first time in the history of colliders. In this report, we summarize the history of KEKB with an emphasis of recent progress.  
 
MOPLT069 Investigation of Injection for the Low-emittance Lattice with New-6.25 ohm Kicker Magnet System at the Photon Factory kicker, factory, lattice, photon 710
 
  • A. Ueda, K. Harada, Y. Kobayashi, T. Mitsuhashi
    KEK, Ibaraki
  We installed 6.25ohm traveling-wave kicker magnet in the Photon Factory to obtain a wide acceptance for the injected beam into the low-emittance lattice of the Photon Factory. We investigate the injection for the low-emittance lattice with this 6.25ohm kicker magnet system. Hence we have optical beam diagnostic systems which source point is inside of injection bump, we use this system for the investigation of injection. The pulse shape of the injection bump was measured by the optical beam profile monitor with high-speed gated camera by using a stored beam. The result of pulse shape of injection bump was agreed with the predicted one by using result of magnetic field measurement, and pulse duration was shorter than twice of revolution time. The instantaneous beam profile of injected beam was observed in turn by turn by using the same beam profile monitor system. We measure the turn by turn position of the injected beam from this observation and compare with a simulation. We also observe a smear out of beam oscillation by nonlinear effect from this instantaneous beam profile measurement.  
 
MOPLT070 FFAG as Phase Rotator for the PRISM Project synchrotron, simulation, kicker, lattice 713
 
  • A. Sato, M. Aoki, Y. Arimoto, Y. Kuno, M. Yoshida
    Osaka University, Osaka
  • Y. Iwashita
    Kyoto ICR, Uji, Kyoto
  • S. Machida, Y. Mori, C. Ohmori, T. Yokoi, K. Yoshimura
    KEK, Ibaraki
  • S. Ninomiya
    RCNP, Osaka
  A Fixed Field Alternating Gradient (FFAG) ring will be used as a phase rotator in the PRISM project. We report a design of the PRISM-FFAG in this paper. PRISM stands for "Phase Rotated Intense Slow Muon beam". It is a project to realize a super muon beam, which combines high-intensity, low-energy, narrow energy-spread and high purity. Its aimed intensity is about 1011-1012 muons per sec. The muon beam will be provided with a low kinetic energy of 20MeV to optimize for the stopped muon experiments. FFAG has some advantageous characteristics to achieve such superb beam. These are a large momentum (longitudinal) acceptance, a wide transverse acceptance with strong focusing, and synchrotron oscillation, which is needed to perform phase rotation. According to simulations, initial energy spread of 20MeV±40% is reduced down to ±6% after 5 turns of muons in the FFAG ring. In the FFAG ring almost all pions decay into muon, hence extracted beam has extremely low pion contamination. A program to construct the PRISM-FFAG ring has been started. It would be completed by the end of JFY 2005.  
 
MOPLT088 Experimental Plasma Wake-field Acceleration Project at the VEPP-5 Injection Complex plasma, acceleration, electron, positron 740
 
  • A.V. Petrenko, A. Burdakov, A.M. Kudryavtsev, P.V. Logatchev, K.V. Lotov, A.N. Skrinsky
    BINP SB RAS, Novosibirsk
  The project of an experimental facility based on the VEPP-5 injection complex is described. Due to a good quality of electron or positron beams and special beam preparation system, the facility opens several possibilities for studies of the plasma wakefield acceleration: high peak beam currents, arbitrary beam profiles, long term beam-plasma interaction (up to the full driver depletion), and precise beam diagnostics. Various wakefield regimes can be experimentally demonstrated and studied: the efficient blow-out regime with a low energy spread and high acceleration rate (up to several GeV per meter); multibunch regime; long bunch instabilities; beam self-organization in plasma; plasma lens. If successfully realized, this experiment becomes a solid argument for feasibility of a high-energy collider based upon the plasma wakefield acceleration.  
 
MOPLT089 SOS-diode Based Pulser for the Injection System of the Collider VEPP-2000 kicker, collider, positron, electron 743
 
  • F.V. Podgorny, B.I. Grishanov, A.S. Kasaev
    BINP SB RAS, Novosibirsk
  We describe high voltage pulsers for supplying of kickers of the collider VEPP-2000 injection system. The high voltage pulse is formed as a result of a sharp break of a high current, accumulated previously in storage elements, by means SOS-diode. Pulse forming lines or inductances could be used as the storage elements. The generators form the quasi-rectangular pulses on the 50-Ohm load. The generator scheme is described also.  
 
MOPLT090 High Pulse and Average Power Low-induction Load damping, linac, extraction, storage-ring 746
 
  • F.V. Podgorny, B.I. Grishanov
    BINP SB RAS, Novosibirsk
  A high pulse and average power low-induction load with a built-in divider is described in this report. The load has a nominal resistance of 25 Ohm and is designed to operate with a repetition rate of up to 50 Hz at a pulse duration (FWHM) of 100 ns, a rise/fall time of 50 ns and a pulse amplitude of up to 40 kV. In this mode the dissipated energy is equal to about 8 J per pulse and average power is up to 400 W. The load can be used as an absorbing load and as a block element in high-voltage engineering.  
 
MOPLT099 NSC KIPT Accelerator on Nuclear and high Energy Physics quadrupole, dipole, electron, target 761
 
  • I.S. Guk, A. Dovbnya, S.G. Kononenko, A.S. Tarasenko
    NSC/KIPT, Kharkov
  • J.I.M. Botman, M.J. Van der Wiel
    TUE, Eindhoven
  One of the main reasons for the outflow of experts in nuclear physics and adjacent areas of science from Ukraine is the absence of modern accelerating facilities, for conducting research in the present fields of interest worldwide in this area of knowledge. A qualitatively new level of research can be achieved by the construction of a new generation accelerator applying the latest developments in the field of electron beam acceleration, in particular on the basis of superconducting accelerating structures of the TESLA type. Such structures may be used for continuous, polarized electron beams, which is crucial e.g. for thin(?) experiments checking modern theoretical models of interactions of nuclear substance, and for beams with high current and extremely short pulses for research in free electron laser and neutron physics. Such a facility will create an opportunity for carrying out research representing the interest of scientists from other countries, which will promote the integration of Ukrainian science into European and worldwide research.  
 
MOPLT100 Magnetic Structure of the NSC KIPT Nuclear-and-high-energy-physics Electron Accelerator electron, storage-ring, quadrupole, dipole 764
 
  • I.S. Guk, A. Dovbnya, S.G. Kononenko, F.A. Peev, A.S. Tarasenko
    NSC/KIPT, Kharkov
  • J.I.M. Botman, M.J. Van der Wiel
    TUE, Eindhoven
  Design options of the magnetic structure of a new proposed accelerator facility at NSC KIPT with a continuous-wave electron beam are described. The accelerator represents a recirculator, based on standard TESLA superconducting accelerating sections in one or two straight sections with a length of 5 or 19 meters. The magnetic system is designed on the basis of the magnetic elements of storage ring EUTERPE, transferred by Eindhoven University to NSC KIPT. The focusing and dispersion functions for several design choices of the magnetic structure are reported. Modeling of the beam movement in the accelerator has been carried out; the beam parameters during acceleration and on accelerator output have been calculated.  
 
MOPLT117 An Electron Front End for the Fermilab Multi-species 8 GeV SCRF Linac linac, electron, emittance, laser 809
 
  • P. Piot, G.W. Foster
    Fermilab, Batavia, Illinois
  Fermilab is considering 8 GeV superconducting linac whose primary mission is to serve as an intense H- injector for the main injector. This accelerator is also planned to be used for accelerating various other species (e.g. electrons and muons). In the present paper we investigate the possibility of such a linac to accelerate a high brightness electron beam to ~7 GeV. We propose a design for the electron front end, based on a photoinjector, and consider the electron beam dynamics along the linac. Start-to-end simulations of the full accelerator for electrons are presented. Finally the potential applications of the such an electron beam are discussed.  
 
MOPLT120 Proposals for Improvements of the Correction of Sextupole Dynamic Effects in the Tevatron Dipole Magnets dipole, sextupole, luminosity, collider 818
 
  • P. Bauer, G. Ambrosio, J. Annala, J. DiMarco, R. Hanft, M. Lamm, M. Martens, P. Schlabach, D. Still, M. Tartaglia, J. Tompkins, G. Velev
    Fermilab, Batavia, Illinois
  It is well known that the sextupole (b2) components in the superconducting dipole magnets decay during the injection plateau and snap back rapidly at the start of the ramp to flat top current. These so-called dynamic effects were originally discovered in the Tevatron. They are compensated for by the chromaticity correctors distributed around the ring. Imperfect control of the chromaticity during the snapback can contribute to beam loss and emittance growth. A thorough investigation of the chromaticity correction in the Tevatron was launched in the context of Run II, including beam chromaticity measurements and extensive magnetic measurements on a series of spare Tevatron dipole magnets. The study has yielded new information about the effect of the powering history on the dynamic b2. A companion paper at this conference describes in detail the results of these magnetic measurements [reference to George Velev's paper]. Study findings have given directive to new proposals for improvement of the b2 snapback correction in the Tevatron, including a revised functional form for the snapback algorithm and the elimination of the beam-less pre-cycle. This paper reports the results of beam studies performed recently to test these improved procedures.  
 
MOPLT123 A Reduced Emittance Lattice for the NLC Positron Pre-damping Ring lattice, wiggler, damping, emittance 827
 
  • I. Reichel, A. Wolski
    LBNL, Berkeley, California
  The Pre-Damping Ring of the Next Linear Collider has to accept a large positron beam from the positron production target, and reduce the emittance and energy spread to low enough values for injection into the Main Damping Ring. A previous version of the lattice yielded an emittance of the extracted beam which was about 20% too large. In order to get the emittance down to the required value the quadrupole magnets in the dispersive regions in the ring were moved horizontally; this modifies the damping partition numbers. In addition, the model of the wigglers has been modified to reflect more closely the magnetic field map. The new lattice design meets damping and emittance requirements. The lattice and dynamic aperture studies are presented.  
 
MOPLT124 Control System of the Small Isochronous ring power-supply, dipole, extraction, ion 830
 
  • J.A. Rodriguez, F. Marti
    NSCL, East Lansing, Michigan
  • E. Pozdeyev
    Jefferson Lab, Newport News, Virginia
  The purpose of this paper is to describe the control system of the Small Isochronous Ring (SIR) developed and built at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU). SIR is a small-scale experiment that simulates the dynamics of intense beams in large accelerators. A 20 to 30 keV hydrogen or deuterium ion bunch is injected in the ring, extracted after a variable number of turns and its longitudinal profile is studied. Information about the electronics used and software written to control different injection line, ring and extraction line elements is included. Some of these elements are magnets, electrostatic quadrupoles, electric and magnetic correctors, scanning wires, emittance measurement system, chopper and a fast Faraday cup.  
 
MOPLT127 Diagnosing the PEP-II Injection System kicker, septum, luminosity, background 833
 
  • F.-J. Decker, M.H. Donald, R.H. Iverson, A. Kulikov, G.C. Pappas, M. Weaver
    SLAC, Menlo Park, California
  The injection of beam into the PEP-II B-Factory, especially into the High Energy Ring (HER) has some challenges. A high background level in the BaBar Detector has so far inhibited us from trickling charge into the HER similar to the Low Energy Ring (LER). Analyzing the injection system has revealed many issues which could be improved. The injection bump between two kickers was not closed, mainly because the phase advance wasn't exactly 180 degrees and the two kicker strengths were not balanced. Additionally we found reflections which kick the stored beam after the main kick and cause the average luminosity to drop about 3% for a 10 Hz injection rate. The strength of the overall kick is nearly twice as high than the design, indicating a much bigger effective septum thickness. Compared with single beam the background is worse when the HER beam is colliding with the LER beam. This hints that the beam-beam force and the observed vertical blow-up in the HER pushes the beam and especially the injected beam further out to the edge of the dynamic aperture or beyond.  
 
MOPLT130 Bunch Pattern with More Bunches in PEP-II luminosity, electron, beam-losses, positron 842
 
  • F.-J. Decker, S. Colocho, A. Novokhatski, M.K. Sullivan, U. Wienands
    SLAC, Menlo Park, California
  The number of bunches in the PEP-II B-Factory has increased over the years. The luminosity followed roughly linear that increase or even faster since we also lowered the spot size at the interaction point. The recent steps from 933 in June of 2003 to about 1320 in February 2004 should have been followed by a similar rise in luminosity from 6.5·1033 1/cm2 1/s to 9.2·1033 1/cm2 1/s. This didn?t happen so far and a peak luminosity of only 7.3·1033 1/cm2 1/s was achieved. By filling the then partially filled by-3 pattern to a completely filled by-3 pattern (1133 bunches) should even give 7.9·1033 1/cm2 1/s with scaled currents of 1400 mA (HER) and 1900 mA (LER). We are typically running about 1300 mA and 1900 mA with 15% more bunches. The bunch pattern is typically by-2 with trains of 14 bunches out of 18. The parasitic beam crossings or electron cloud effects might play a role in about a 10% luminosity loss. Also the LER x-tune could be pushed further down to the ? integer in the by-3 pattern. On the other hand we might not push the beam-beam tune shift as hard as in June of 2003 since we started trickle injection and therefore might avoid the highest peak luminosity with a higher background. A mixed pattern with a by2-by3 setup (separation of 2, 3, 2, 3 ?) would give totally filled a slightly higher number of bunches (1360), but near the interaction point there would be only one parasitic crossing per beam lowering the tune shift by two.  
 
MOPLT143 Results and Plans of the PEP-II B-Factory luminosity, positron, beam-beam-effects, electron 875
 
  • J. Seeman, J. Browne, Y. Cai, S. Colocho, F.-J. Decker, M.H. Donald, S. Ecklund, R.A. Erickson, A.S. Fisher, J.D. Fox, S.A. Heifets, R.H. Iverson, A. Kulikov, A. Novokhatski, M.T.F. Pivi, M.C. Ross, P. Schuh, T.J. Smith, K. Sonnad, M. Stanek, M.K. Sullivan, P. Tenenbaum, D. Teytelman, J.L. Turner, D. Van Winkle, U. Wienands, M. Woodley, Y.T. Yan, G. Yocky
    SLAC, Menlo Park, California
  • M.E. Biagini
    INFN/LNF, Frascati (Roma)
  • J.N. Corlett, C. Steier, A. Wolski, M.S. Zisman
    LBNL, Berkeley, California
  • W. Kozanecki
    CEA/DSM/DAPNIA, Gif-sur-Yvette
  • G. Wormser
    IPN, Orsay
  PEP-II is an e+e- B-Factory Collider located at SLAC operating at the Upsilon 4S resonance. PEP-II has delivered, over the past four years, an integrated luminosity to the BaBar detector of over 175 fb-1 and has reached a luminosity over 7.4x1033/cm2/s. Steady progress is being made in reaching higher luminosity. The goal over the next few years is to reach a luminosity of at least 2x1034/cm2/s. The accelerator physics issues being addressed in PEP-II to reach this goal include the electron cloud instability, beam-beam effects, parasitic beam-beam effects, trickle injection, high RF beam loading, lower beta y*, interaction region operation, and coupling control.  
 
MOPLT144 Design for a 1036 Super-B-factory at PEP-II luminosity, interaction-region, factory, collider 878
 
  • J. Seeman, Y. Cai, F.-J. Decker, S. Ecklund, A.S. Fisher, J.D. Fox, S.A. Heifets, A. Novokhatski, M.K. Sullivan, D. Teytelman, U. Wienands
    SLAC, Menlo Park, California
  Design studies are underway to arrive at a complete parameter set for a very high luminosity e+e- Super B-Factory (SBF) in the luminosity range approaching 1036/cm2/s. The design is based on a collider in the PEP-II tunnel but with an upgraded RF system (higher frequency), magnets, vacuum system, and interaction region. The accelerator physics issues associated with this design are reviewed as well as the site and power constraints. Near term future studies will be discussed.  
 
MOPLT146 Trickle-charge: a New Operational Mode for PEP-II background, luminosity, diagnostics, feedback 881
 
  • J.L. Turner, S. Colocho, F.-J. Decker, S. Ecklund, A.S. Fisher, R.H. Iverson, C. O'Grady, J. Seeman, M.K. Sullivan, M. Weaver, U. Wienands
    SLAC, Menlo Park, California
  • W. Kozanecki
    CEA/DSM/DAPNIA, Gif-sur-Yvette
  In regular top-up-and-coast operation, PEP-II average luminosity is about 70…75% of the peak luminosity due to detector ramp-down and ramp-up times plus the time it takes to top-up both beams. We recently commissioned a new operational mode where the Low Energy Ring is injected continuously without ramping down the detector. The benefits?increased luminosity lifetime and roughly half the number of top-ups per shift?were expected to give an increase in delivered luminosity of about 15% at the same peak luminosity; this was confirmed in test runs. In routine trickle operation, however, it appears that the increase in delivered luminosity is more than twice that due to an increase in availability credited to the more stable operating conditions during trickle operation. In this paper we will present our operational experience as well as some of the diagnostics we use to monitor and maintain tuning of the machine in order to control injection background and protect the detector. Test runs are planned to extend trickle-charge operation to the High Energy Ring as well.  
 
MOPLT158 Cost Optimization of Non-Scaling FFAG Lattices for Muon Acceleration lattice, acceleration, closed-orbit, extraction 902
 
  • J.S. Berg, R. Palmer
    BNL, Upton, Long Island, New York
  Fixed Field Alternating Gradient (FFAG) accelerators are a promising idea for reducing the cost of acceleration for muon accelerators as well as other machines. This paper presents an automated method for designing these machines to certain specifications, and uses that method to find a minimum cost design. The dependence of this minimum cost on various input parameters to the system is given. The impact of the result on an FFAG design for muon acceleration is discussed.  
 
MOPLT164 Bunch Patterns and Pressure Rise in RHIC electron, simulation, vacuum, background 914
 
  • W. Fischer, U. Iriso
    BNL, Upton, Long Island, New York
  The RHIC luminosity is limited by pressure rises with high intensity beams. At injection, the dominating cause for the pressure rise was shown to be electron clouds. We discuss the distributions of bunches along the circumference that minimize the electron cloud effect in RHIC. Experimental data are compared with simulation results, and experiences at the B-factories.  
 
MOPLT167 RHIC Operation with Longitudinally Polarized Protons polarization, resonance, proton, 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.  
 
MOPLT171 A Pratical Demonstration of the CRFQ Storage Ring rfq, focusing, proton, 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 proton, 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.  
 
MOPLT179 Beam Scrubbing for RHIC Polarized Proton Opearation electron, proton, 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.  
 
TUZACH02 Ultra-high Gradient Compact Accelerator Developments plasma, laser, electron, acceleration 74
 
  • G.J.H. Brussaard, M.J. Van der Wiel
    TUE, Eindhoven
  Continued development of relatively compact, although not quite 'table-top', lasers with peak powers in the range up to 100 TW has enabled laser-plasma-based acceleration experiments with amazing gradients of up to 1 TV/m. In order to usefully apply such gradients to 'controlled' acceleration, various hurdles need to be overcome. The main one is that of well-synchronized injection into a sub-mm to micron wavelength plasma wave. The talk will describe the various physics regimes of laser wakefield acceleration, and the two classes of experiments being pursued. One is that of atmospheric-density plasmas, non-linear wakefields with extreme gradients (hundreds of GV/m)and 'internal injection' of few-femtosecond electron bunches. A second class involves modest-density plasmas,wakefields of order 1 GV/m and external injection of (sub)-ps bunches. The state-of-the-art of these experiments will be covered, including the progress on plasma waveguiding of TW pulses over many diffraction lengths. The talk will also provide an outlook for the coming few years. This part includes proposed schemes for improvements in the area of injection, such as 'all-optical' injection and injection based on GV/m 'pulsed-DC' photoguns.  
Video of talk
Transparencies
 
TUZBCH01 Beam Quality Preservation in the CERN PS-SPS Complex emittance, electron, impedance, extraction 78
 
  • G. Arduini
    CERN, Geneva
  The LHC will require beams of unprecedented transverse and longitudinal brightness. Their production imposes tight constraints on the emittance growth in each element of the LHC injector chain, namely the PS-SPS Accelerator Complex. The problems encountered at the different stages of the acceleration in the complex span a wide range of topics, such as injection matching, RF gymnastics, space charge, transverse and longitudinal single- and coupled-bunch instabilities, and electron cloud effects. The measurement techniques developed and applied to identify and study the various sources of emittance dilution to the high precision required for the LHC beams and the solutions found to control such phenomena are illustrated.  
Video of talk
Transparencies
 
TUXLH01 Machine Protection Issues and Strategies for the LHC beam-losses, kicker, proton, 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
 
TUYLH03 Challenges facing the Generation of MW Proton Beams using Rapid Cycling Synchrotrons proton, 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
 
TUPKF009 RF Control of the Superconducting Linac for the BESSY FEL simulation, klystron, linac, beam-loading 973
 
  • J. Knobloch, A. Neumann
    BESSY GmbH, Berlin
  In the BESSY-FEL superconducting linac, precise RF control of the cavities' voltage is imperative to maintain a bunch-to-bunch time jitter of less than 50 fs for synchronization in the HGHG section. The average beam loading is less than 1.5 kW/m and the cavity bandwidth is small so that high-gain RF feedback is required. Noise, in particular microphonic detuning, strongly impact the achievable level of control. Presented here are simulations of the cavity-feedback system, taking into account beam loading and noise sources such as measurement noise, microphonics and injection jitter. These simulations are used to estimate the resultant time and energy jitter of the bunches as they enter the HGHG section of the BESSY FEL.  
 
TUPKF032 COD Correction by Novel Back-leg at the KEK-PS Booster power-supply, booster, beam-losses, closed-orbit 1030
 
  • S. Ninomiya, K. Satoh, H. Someya, M. Toda
    KEK, Ibaraki
  The COD correction is performed by using new driving system of back-leg windings. Two back-leg coils of the separate magnets are connected to make a closed circuit in which the induced voltages of the two magnets have opposite phases to each other. When the current source is inserted into the closed loop, the current drives the two magnets with opposite polarities. If the pair of magnets is properly selected, the current effectively corrects the orbit distortion. The selection rule of the pair is as follows; one is the magnet at the maximum distortion and the second magnet is that separated with the betatron phase of -90deg. The correction system at the KEK-PS Booster reduced the COD to less than 1/5 of that without correction, and increased the capture efficiency. The average beam intensity of our Booster is increased from 2E+12 to 2.6E+12ppp.  
 
TUPKF055 Space-charge-limited Magnetron Injection Guns for Gyroklystrons cathode, simulation, gun, electron 1072
 
  • W. Lawson
    Maryland University, College Park, Maryland
  We present the results of several space-charge-limited (SCL) magnetron injection gun (MIG) designs which are intended for use with a 500 kV, 500 A gyroklystron with accelerator applications. The design performances are compared to that of a temperature-limited (TL) gun that was constructed for the same application. The SCL designs yield similar values for beam quality, namely an axial velocity spread under 3% for an average perpendicular-to-parallel velocity ratio of 1.5. The peak electric fields and the cathode loadings of the SCL designs are somewhat higher than for the TL design. Three designs are described in this paper. In the first design the space-charge limit is achieved by recessing the emitter into the cathode. The other two designs have control electrodes to which a voltage can be applied to change the beam current independently of the beam voltage. One of these designs can accept a bias sufficiently high to cut off the current completely, so that a DC power supply with pulsed grid operation is possible. Details of all designs as well as a discussion of the advantages and disadvantages of the SCL designs as compared to the TL design will be given.  
 
TUPLT006 Simple Analytic Formulae for the Properties of Nonscaling FFAG Lattices quadrupole, lattice, betatron, radio-frequency 1138
 
  • S.R. Koscielniak
    TRIUMF, Vancouver
  • M.K. Craddock
    UBC & TRIUMF, Vancouver, British Columbia
  A hallmark of the "non-scaling" FFAG lattices recently proposed for neutrino factories and muon colliders is that a wide range of momentum is compacted into a narrow radial band; dL/L is of order 10(-3) for dp/p of order unity. This property is associated with the use of F0D0 or FDF triplet lattices in which the F magnet provides a reverse bend. In this paper simple analytic formulae for key lattice properties, such as orbit displacement and path length as a function of momentum, are derived from thin-element models. These confirm the parabolic dependence of path-length on momentum observed with standard orbit codes, reveal the factors which should be adjusted to minimize its variation, and form a useful starting point for the thick-element design (for which analytic formulae are also presented). A key result is that optimized doublet, F0D0 and triplet cells of equal length and phase advance have equal path-length performance. Finally, in the context of a 10-20 GeV/c muon ring, the thin-element formulae are compared against lattice optical properties computed for thick-element systems; the discrepancies are small overall, and most discernible for the triplet lattices.  
 
TUPLT009 Trajectory Correction Studies for the CNGS Proton Beam Line proton, 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, proton, 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.  
 
TUPLT011 The LHC Lead Ion Injector Chain ion, electron, linac, vacuum 1153
 
  • K. Schindl, A. Beuret, A. Blas, J. Borburgh, H. Burkhardt, C. Carli, M. Chanel, T. Fowler, M. Gourber-Pace, S. Hancock, C.E. Hill, M. Hourican, J.M. Jowett, K. Kahle, D. Kuchler, A.M. Lombardi, E. Mahner, D. Manglunki, M. Martini, S. Maury, F. Pedersen, U. Raich, C. Rossi, J.-P. Royer, R. Scrivens, L. Sermeus, E.N. Shaposhnikova, G. Tranquille, M. Vretenar, T. Zickler
    CERN, Geneva
  A sizeable part of the LHC physics programme foresees heavy ion (lead-lead) collisions with a design luminosity of 1027 cm-2 s-1. This will be achieved after an upgrade of the ion injector chain comprising Linac3, LEIR, PS and SPS machines. Each LHC ring will be filled in ~10 minutes with ~600 bunches, each of 7 107 Pb ions. Central to the scheme is the Low Energy Ion Ring (LEIR), which transforms long pulses from Linac3 to high-brilliance bunches by means of 6D multi-turn injection and accumulation via electron cooling. Major limitations along the chain, including space charge, intra-beam scattering, vacuum issues, and emittance preservation are highlighted. The conversion from LEAR (Low Energy Antiproton Ring) to LEIR includes new magnets and power converters, high-current electron cooling, broad-band RF cavities, upgraded beam diagnostics, and UHV vacuum equipment relying on beam scrubbing to achieve a few 10-12 mbar. Major hardware changes in Linac3 (Electron Cyclotron Resonance source, repetition rate, energy ramping cavity), PS (new injection hardware, elaborate RF gymnastics, stripping insertion), and SPS (100 MHz system) are described. An early beam scenario, using fewer bunches but the same bunch intensity to deliver a lower luminosity, reduces the work required for LHC ion operation in spring 2008.  
 
TUPLT014 Comparative Design Studies of a Super Buncher for the 72 MeV Injection Line of the PSI Main Cyclotron cyclotron, impedance, simulation, linac 1162
 
  • J.-Y. Raguin, A. Adelmann, M. Bopp, H. Fitze, M. Pedrozzi, P. Schmelzbach, P. Sigg
    PSI, Villigen
  The envisaged current upgrade from 2 to 3 mA of the PSI 590-MeV main cyclotron requires an increase of the global accelerating voltage of the 50-MHz cavities which leads to a nearly unacceptable RF requirement for the 150-MHz flattop cavity. In order to preserve the longitudinal acceptance and transmission of the machine while relaxing the high demands on the flattop system, it is conceivable to install a buncher in the 72-MeV injection line. To this end, normal-conducting 150-MHz half-wave resonators and 500-MHz two-gap drift-tube cavities have been designed and optimised for minimum input power and peak surface fields. The dependence of the RF properties (Q0, shunt impedances and peak fields) with beam apertures and gap voltages compatible with beam-dynamics requirements are presented.  
 
TUPLT016 Improved Performance of the Heavy Ion Storage Ring ESR electron, ion, heavy-ion, storage-ring 1168
 
  • M. Steck, K. Beckert, P. Beller, B. Franczak, B.  Franzke, F. Nolden
    GSI, Darmstadt
  The heavy ion storage ring ESR at GSI allows experiments with stable and radioactive heavy ions over a large range of energies. The energy range available for operation with completely stripped ions has recently been extended to energies as low as 3 MeV/u. Even for bare uranium such low energies can be provided by deceleration of the ions which are stripped to high charge states in a foil at energies of 300-400 MeV/u. After injection the beam is cooled and decelerated in an inverse synchrotron mode interspersed with electron cooling at an intermediate energy. At the lowest energy of 3 MeV/u some hundreds of thousands ions could be electron cooled after deceleration. At energies of 10-20 MeV/u physics experiments with stored and slowly extracted beam have been performed with some million decelerated cooled ions. The cooling of radioactive ions by a combination of stochastic pre-cooling and final electron cooling has been demonstrated. The hot fragment beam, which was injected at an energy of 400 MeV/u, was cooled in about 6 s to a quality useful for precision experiments.  
 
TUPLT017 Achievements of the High Current Beam Performance of the GSI Unilac ion, emittance, rfq, heavy-ion 1171
 
  • W. Barth, L. Dahl, J. Glatz, L. Groening, S.G. Richter, S. Yaramishev
    GSI, Darmstadt
  The present GSI-accelerator complex is foreseen to serve for the future synchrotron SIS100 as an injector for up to 1012 U28+ particles/sec. The High Current Injector of the Unilac was successfully commissioned five years ago. An increase of more than two orders of magnitude in particle number for the heaviest elements in the SIS had to be gained. Since that time many different ion species were accelerated in routine operation. In 2001 a physics experiment used 2×109 Uranium ions per spill. In order to meet this request the MEVVA ion source provided for the first time in routine operation a high intense Uranium beam. The main purpose for the machine development program during the last two years was the enhancement of the intensity for Uranium beams. Different hardware measures and a huge investigation program in all Unilac-sections resulted in an increase of the uranium intensity by a factor of 7. The paper will focus on the measurements of beam quality, as beam emittance and bunch structure for Megawatt-Uranium beams. Additionally the proposed medium- and long-term hardware measures will be described, which should gain in the required uranium intensity to fill the SIS up to the space charge limit.  
 
TUPLT020 High Intensity Uranium Operation in SIS18 ion, septum, beam-losses, acceleration 1180
 
  • P.J. Spiller, K. Blasche, P. Hülsmann, A. Kraemer, H. Ramakers, H.R. Sprenger
    GSI, Darmstadt
  For the present experiment program and the planned international accelerator facility at GSI, the space charge limit of SIS18 for highly(4x1010) and intermediate (2.7x1011) charged uranium ions shall be reached within the next four years. Furthermore, measures to increase the repetition- and ramp rate up to 4 Hz with 10 T/s have been progressed. The present state of intensities per cycle and the limitations will be described. In connection with the planned enhancement of heavy ion intensities, protection, interlock and diagnostic systems, especially for the injection- and extraction devices have been prepared. Special attention is drawn on the insights which were achieved with respect to the operation at dynamic vacuum conditions. Results of R&D work with the goal to increase the intensity threshold and to improve the beam life time will be summarized. Furthermore, the specific upgrade program and schedule for the SIS18 booster mode will be presented.  
 
TUPLT025 Matching of a C6+ Ion Beam from a Laser Ion Source to a RFQ ion, rfq, laser, ion-source 1195
 
  • R. Becker, R.A. Jameson, A. Schempp
    IAP, Frankfurt-am-Main
  • T. Hattori
    RIKEN, Saitama
  • N. Hayashizaki, H. Kashiwagi
    RLNR, Tokyo
  • M. Okamura
    RIKEN/RARF/CC, Saitama
  • K. Yamamoto
    RIKEN/RARF/BPEL, Saitama
  A laser ion source, driven by a Nd-YAG laser can provide more than 100 mA of C6+ ions for a duration of about 1 μs, which is well matching the task of single-turn injection into synchrotrons for hadron tumor therapy with light ions. The ?direct? injection scheme has been improved by providing a design, which reduces the surface field strength to less than 30 kV/cm on all critical parts on relative negative potential. The new design keeps the advantage of divergent ion emission and acceleration, which seems to be the only way to keep the surface fields in limits, but includes a decelerating electrostatic lens on birth potential of the ions to refocus the emerging ion beam to the RFQ entrance. The whole design is very compact and allows for electrostatic steering between the ion source and the RFQ.  
 
TUPLT027 Status of the HITRAP Decelerator Linac at GSI rfq, linac, ion, heavy-ion 1201
 
  • C.A. Kitegi, A. Bechtold, U. Ratzinger, A. Schempp
    IAP, Frankfurt-am-Main
  • T. Beier, L. Dahl, C. Kozhuharov, W. Quint, M. Steck
    GSI, Darmstadt
  • S. Minaev
    ITEP, Moscow
  Within the European Network HITRAP (heavy Ion trap) trapped and cooled higly charged ions up to U92+ will become avilable for a variety of attractive experiments in atomic physics. Heavy ions are produced, accelerated and stripped in the GSI accelerator complex and are stored in the ESR down to 4 MeV/u. To be captured in HITRAP, ions have to be decelerated to energies below 6 keV/u. The decelerator proposed to achieve these energies is a combination of an IH Drift tube cavity operating in the H11(0) mode and a RFQ. The operating frequency is 108.408MHz . The A/q range of the linac is up to 3. A very efficient deceleration by up to 11 MV along the 2.7 m long IH cavity with a rf power of 200kw is achieved by applying the KONUS beam dynamics. The deceleration from 500 A.keV down 6A.keV is provided by a 1.8 m long 4-rod RFQ.The beam dynamics as well as the cavity design of that linac will be described.The decelerator linac will be installed in the reinjection beam line and is being developed in collaboration between GSI and the Frankfurt University .  
 
TUPLT041 Ultra-low Energy Antiprotons at FLAIR antiproton, storage-ring, electron, ion 1240
 
  • C.P. Welsch, M. Grieser, D. Orlov, J. Ullrich, A. Wolf, R. von Hahn
    MPI-K, Heidelberg
  The Future Accelerator Facility for Beams of Ions and Antiprotons at Darmstadt will produce the highest flux of antiprotons in the world. So far it is foreseen to accelerate the antiprotons to high energies (3-15 GeV) for meson spectroscopy and other nuclear and particle physics experiments in the HESR (High Energy Storage Ring). Within the planned complex of storage rings, it is possible to decelerate the antiprotons to about 30 MeV kinetic energy, opening up the possibility to create low energy antiprotons. In the proposed FLAIR facility the antiprotons shall be slowed down in a last step from 300 keV to 20 keV in an electrostatic storage ring (USR) for various in-ring experiments as well as for their efficient injection into traps. In this energy range - especially if one thinks about realizing a real multi-purpose facility with not only antiprotons, but also various highly-charged radioactive ions to be stored and investigated - electrostatic storage rings have clear advantages compared to their magnetic counterparts. In case one envisions to even approach the eV range, electrostatic machines are the only possible choice. This contribution presents the layout and design parameters of the USR.  
 
TUPLT042 Ring of FIRE ion, storage-ring, quadrupole, lattice 1243
 
  • C.P. Welsch, J. Ullrich
    MPI-K, Heidelberg
  • R. Doerner, H. Schmidt-Boecking
    IKF, Frankfurt-am-Main
  • C. Glaessner, K.-U. Kuehnel, A. Schempp
    IAP, Frankfurt-am-Main
  A small electrostatic storage ring is the central machine of the Frankfurt Ion stoRage Experiments which will be build up at the new Stern-Gerlach-Center of Frankfurt university. With ion energies up to 50 keV it will allow new methods to analyze complex many-particle systems from atoms to very large bio molecules. The high luminosity of the beam allows measurements with many orders of magnitude better resolution compared to traditional measurements. It will be combined with existing experiments, like the reaction microscope COLTRIMS and the ECR ion source. In comparison to earlier designs, the ring lattice was modified in many details: Problems in earlier designs were related with e.g. the detection of light particles and highly charged ions with different charge states. Therefore, the deflectors were redesigned completely, allowing a more flexible positioning of the diagnostics. In this contribution the final design of the storage ring is presented and the layout of all elements given. First results from vacuum measurements in the recently assembled quarter ring section are summarized.  
 
TUPLT043 Status of the Cooler Synchrotron COSY-Juelich proton, 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.  
 
TUPLT044 Delta-T Procedure for Superconducting Linear Accelerator linac, pick-up, simulation, acceleration 1249
 
  • A. Bogdanov, R. Maier, Y. Senichev
    FZJ/IKP, Jülich
  Development of the tune-up procedure for a linear accelerator is the next important stage after the design is complete. Conventional delta-T procedure developed for tuning of a normal-conducting linear accelerator by Crandall allows setting up of accelerating field amplitude and phase in cavity with known phase velocity. However, application of the delta-T procedure to a superconducting linac meets some difficulties. In particular, the synchronous phase velocity in superconducting linac is determined by RF phase shift between cavities, but not by geometrical size of accelerating cells as in normal conducting linac. Additionally, in superconducting linac the smaller phase advance leads to an insensibility of particles at the cavity exit to the variation of the electric field inside the cavity. In the paper we consider the modified delta-T procedure adjusted for superconducting linac. Numerical simulations prove that by proposed technique both tasks of preservation of necessary stable region motion and providing the beam with required final energy can be successfully solved.  
 
TUPLT046 Luminosity Considerations for Internal and External Experiments at COSY target, luminosity, extraction, proton 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.  
 
TUPLT065 Beams from RF Ovens and ECR Ion Sources plasma, ion, ion-source, electron 1303
 
  • M. Cavenago
    INFN/LNL, Legnaro, Padova
  • T. Kulevoy, S. Petrenko
    ITEP, Moscow
  Beam of silver, copper and recently platinum were produced with the radiofrequency oven technique. The ECRIS (Electron Cyclotron Resonance Ion Source) can be conveniently considered as a charge breeder for any injection device; this approach allows to compare the injection of metals from ovens with other techniques discussed in the literature, like the injection from mevva (Metal Vapor Vacuum Arc) sources or the injection of single charged RIB (radioactive ion beams) or the simple injection of heavy gas. Extensive experiments extracting beams of copper (charge up 13+) or silver (charge up to 19+) or xenon (charge up 20+) with the same ECRIS condition are described, and advantage of rf oven over gas injection are discussed; in particular the oven crucible can be easily voltage biased up to -400 V, to modify ECRIS plasma shape. Heating the tantalum crucibles over 2300 K (average temperature) requires careful axial alignment to avoid the formation of hot spots; preliminary evidence of this effect and its numerical modeling are also described.  
 
TUPLT075 Improvements of SPring-8 Linac towards Top-up Operation linac, synchrotron, vacuum, power-supply 1327
 
  • S. Suzuki, T. Asaka, H. Dewa, H. Hanaki, T. Kobayashi, T. Masuda, A. Mizuno, T. Taniuchi, H. Tomizawa, K. Yanagida
    JASRI/SPring-8, Hyogo
  The top-up operation of the SPring-8 storage ring will start in May, 2004. In order to realize alternative injection into the booster synchrotron in the top-up operation and the NewSUBARU, an AC bending magnet replaced the DC bending magnet in the beam transport line to the booster synchrotron. This magnet operates at 1 Hz with a trapezoid current pattern. The 1-GeV electron beam goes at the bottom of the current pattern to the NewSUBARU or at the top of the pattern to the booster synchrotron. In order to obtain the higher reliability of the linac for the top-up operation, reinforcement of the beam monitor systems, further improvement of RF phase stability and upgrade of the control system were required. BPM?s has been newly installed in energy dispersion sections, and beam transport feedback control is in development. The phase variation in the RF system was reduced by the regulation of the gas pressure in the waveguide of the klystrons drive system. We re-engineered the VME systems to maximize availability of the linac operation considering its reliability, usability, expandability and flexibility.  
 
TUPLT076 Optimization of Sextupole Strengths in a Storage Ring for Top-up Operation sextupole, optics, storage-ring, synchrotron 1330
 
  • H. Tanaka, T. Ohshima, K. Soutome, M. Takao, H. Takebe
    JASRI/SPring-8, Hyogo
  In top-up operation of a light source, electron or positron beams are frequently injected to keep the stored current constant. Closing an injection bump orbit is thus critically important not to disturb precise experiments. However, there are sextupole magnets inside the injection bump in the SPring-8 storage ring and the bump never closes all over the bump amplitude due to the sextupole nonlinearity. To solve the problem, we proposed a scheme based on minimum condition for the injection bump leakage. The scheme only restricts the sextupole strengths within the bump. Introduction of other sextupole families outside the bump can enlarge the dynamic aperture (DA) of the ring with keeping the minimum leakage. To find the best solution, we optimized the sextupole strengths changing the number of sextupole family as a parameter. The simulation shows that addition of two sextupole families sufficiently enlarges DA. Cabling of the sextupole magnets was partly changed in the summer 2003 and the effects of the strength optimization on the bump leakage, injection efficiency and beam lifetime has been investigated experimentally. We present the obtained results compared with the simulations.  
 
TUPLT079 Opposite Field Septum Magnet System for the J-PARC 50GeV Ring Injection septum, synchrotron, vacuum, proton 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.  
 
TUPLT080 Design of the Beam Transportation Line from the Linac to the 3-GeV RCS for J-PARC simulation, emittance, linac, quadrupole 1342
 
  • T. Ohkawa
    JAERI, Ibaraki-ken
  • M. Ikegami
    KEK, Ibaraki
  L3BT is beam transportation line from the linac to the 3-GeV RCS which is the part of the accelerators for the High-Intensity Proton Accelerator Facility Project, J-PARC. For the requirement of the beam loss minimization, the L3BT does not only connect the linac to the 3GeV RCS, but also modifies the linac beam to the acceptable shape for the 3-GeV RCS. The required beam parameters at the injection point of the RCS are momentum spread < ±0.1% (100%)and transverse emittance < 4pmm.mrad (99%). To achieve these beam qualities, the L3BT should have following functions: momentum compaction, halo scraping and beam diagnostics. In this paper, results of the design and beam simulation of the L3BT are presented.  
 
TUPLT099 A Kicker Pulse Power Supply with Low Jitter kicker, power-supply, storage-ring, booster 1387
 
  • C.-S. Fann, J.-P. Chiou, S.Y. Hsu, K.-B. Liu
    NSRRC, Hsinchu
  The performance of kicker pulse power supplies is the main parameter to increase injection efficiency of storage ring that is an important issue for laboratory of synchrotron radiation research. The output current waveform of a kicker pulse power supply with low timing jitter is our goal for years that must satisfy the Top-Up mode injection requirement of NSRRC. In the past years kicker pulse power supplies of storage ring of NSRRC are immersed in isolation oil to sustain high voltage operational environment that led difficult to maintain, electronic component degrading and uneasy to tune parameters. Air-cooling and air-isolation is adopted in the new design structure for kicker pulse power supply system and an pre-trigger unit MA2709A is installed to trigger thyratron tube CX1536A, a kicker pulse power supply with low timing jitter 1~2ns(p-p) is obtained and could satisfy for Top-Up mode injection and maintenance is more easier than before.  
 
TUPLT103 Possibilities for Experiments with Rare Radioactive Ions in a Storage Ring Using Individual Injection ion, kicker, electron, target 1393
 
  • A.O. Sidorin, I.N. Meshkov, A.O. Sidorin, A. Smirnov, E. Syresin, G.V. Troubnikov
    JINR, Dubna, Moscow Region
  • T. Katayama
    CNS, Saitama
  • W. Mittig, P. Roussel-Chomaz
    GANIL, Caen
  A radioactive ion beam produced at a target bombarded with a primary beam has after a fragment separator a relatively large emittance and small production rate. For instance, typical flux of 132Sn isotope at the exit of fragment-separator is about 5×105 ions/s. Conventionally used scheme of the ion storage in a ring based on multitutrn injection and (or) RF stacking and stochastic cooling application can not provide a high storage rate at so pure intensity especially for short lived isotopes. In this report we discuss an alternative storage scheme which is oriented to the continuous ion beam from fragment separator at production rate of 104 ions/s or even less. It is based on the fact, that at low production rate the parameters of each particle can be measured individually with rather high accuracy. The particle trajectory can be individually corrected in a transfer channel from fragment separator to the storage ring using system of fast kickers. A fast kicker in the ring synchronized with a circulating bunch provides continuous injection of the ions. The scheme permits to store the ion number required for precise mass measurements and internal target experiment. A hope to obtain large luminosity of ion-electron collisions is related with a possibility of the ion beam crystallization at small particle number.  
 
TUPLT132 Investigation of Injection through Bending Magnet Fringe Fields in X-rays Source NESTOR dipole, storage-ring, linac, vacuum 1434
 
  • A. Mytsykov, P. Gladkikh, A.V. Rezaev, A.Y. Zelinsky
    NSC/KIPT, Kharkov
  In paper injection in the X-rays source NESTOR through fringe fields of a bending magnet is considered. The simulation of a motion of a beam of charged particles through 3-d fields of magnetic devices of the injection channel, which ones is located on a ring, are performed. The focusing properties of the injection channel are determined.  
 
TUPLT137 Comparative Simulation Studies of Electron Cloud Build-up for ISIS and Future Upgrades simulation, proton, electron, 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).  
 
TUPLT154 Aperture Studies for the Fermilab AP2 Anti-proton Line lattice, antiproton, kicker, chromatic-effects 1491
 
  • I. Reichel, M. Placidi, M.S. Zisman
    LBNL, Berkeley, California
  • K. Gollwitzer, S. Werkema
    Fermilab, Batavia, Illinois
  The AP2 beamline transports anti-protons from the production target to the Debuncher ring. In the past the observed aperture has been smaller than that estimated from linear, on-energy optics. We have investigated possible reasons for the aperture limitation and have identified possible sources, including residual vertical dispersion from alignment errors and chromatic effects due to very large chromatic lattice functions. Some experiments have already been performed to study these effects. We present results of the experimental and theoretical studies and possible remedies.  
 
TUPLT171 ORBIT Simulations of the SNS Accumulator Ring simulation, electron, linac, space-charge 1530
 
  • J.A. Holmes, S.C. Bunch, S.M. Cousineau, V.V. Danilov, S. Henderson, A. Shishlo
    ORNL/SNS, Oak Ridge, Tennessee
  • M. Plum
    LANL, Los Alamos, New Mexico
  • Y. Sato
    IUCF, Bloomington, Indiana
  As SNS undergoes construction, many detailed questions arise concerning strategies for commissioning and operating the accumulator ring. The ORBIT Code is proving to be an indispensible tool for addressing these questions and for providing guidance to the physicists and decision makers as operation draws near. This paper shows the application of ORBIT to a number of ring issues including exclusion of the HEBT RF cavities during commissioning, the detailed effect of the injection chicane magnets on the beam, the effects and correction of magnet alignment and multipole errors, debunching of the linac 402.5 MHz beam structure, the injection of self consistent uniform beam configurations, and initial electron cloud simulations.  
 
TUPLT177 RHIC Optics Measurements at Different Working Point optics, dipole, quadrupole, closed-orbit 1541
 
  • R. Calaga, M. Bai, S. Peggs, T. Roser, T. Satogata
    BNL, Upton, Long Island, New York
  Working point scans at RHIC were performed during 2004 to determine the effect on lifetime and luminosity. Linear optics were measured for different working point tunes by exciting coherent oscillations with the aid of RHIC AC dipoles. Two methods to measure the beta functions and phases are presented and compared: a conventional technique, and a new method based on singular value decomposition (SVD). The performance of a 3-bump beta wave algorithm to identify quadrupole error sources is also presented.  
 
TUPLT184 Operational Measurement of Coupling by Skew Quadrupole Modulation coupling, quadrupole, heavy-ion, closed-orbit 1559
 
  • Y. Luo, P. Cameron, R. Lee, A. Marusic, F.C. Pilat, T. Roser, D. Trbojevic, J. Wei
    BNL, Upton, Long Island, New York
  The measurements of betatron coupling via skew quadrupole modulation is a new diagnostics technique that has been recently developed and tested at RHIC. By modulating the current of different skew quadrupole families with different frequencies and measuring the resulting eigentunes response with a high resolution phase lock loop (PLL) system, it is possible to determine the projections of the residual coupling coefficients. We report the results of extensive beam studies carried on at RHIC injection, store energy and on the ramp. The capability of measuring coupling on the ramp opens the possibility of continuous coupling corrections during acceleration.  
 
TUPLT185 Principle of Skew Quadrupole Modulation to Measure Betatron Coupling coupling, quadrupole, simulation, betatron 1562
 
  • Y. Luo, F.C. Pilat, T. Roser, D. Trbojevic, J. Wei
    BNL, Upton, Long Island, New York
  The idea of modulating Skew Qudrupoles to measure the ring betatron coupling was put forth by T. Roser. In this paper, analytical solutions for this technique is given. Simulation are also carried out based on RHIC. And other relevent issues concerning this technique's application are also discussed. All of them show this idea of modulating skew qudrupoles to measure the betatron coupling are applicable.  
 
TUPLT190 Acceleration of Polarized Beams using Multiple Strong Partial Siberian Snakes resonance, extraction, polarization, betatron 1577
 
  • T. Roser, L. Ahrens, M. Bai, E.D. Courant, J. Glenn, R.C. Gupta, H. Huang, A.U. Luccio, W.W. MacKay, N. Tsoupas, E. Willen
    BNL, Upton, Long Island, New York
  • M. Okamura, J. Takano
    RIKEN, Saitama
  Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult since depolarizing spin resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions. Using a 20 - 30 % partial Siberian snake both imperfection and intrinsic resonances can be overcome. Such a strong partial Siberian snake was designed for the Brookhaven AGS using a dual pitch helical superconducting dipole. Multiple strong partial snakes are also discussed for spin matching at beam injection and extraction.  
 
TUPLT191 Transverse Optics Improvements for RHIC Run 4 optics, power-supply, dipole, sextupole 1580
 
  • J. Van Zeijts
    BNL, Upton, Long Island, New York
  The magnetic settings in RHIC are driven by an online model, and the quality of the resulting lattice functions depend on the correctness of the settings, including knowledge of the magnet transfer-functions. Here we first present the different inputs into the online model, including dipole sextupole compenents, used to set tunes and chromaticities along the ramp. Next, based on an analysis of measured tunes and chromaticities along the fy03 polarized proton ramp, we present predictions for quadrupole transfer-function changes. The changes are implemented for the fy04 Au ramp, and we show the improved model agreement for tunes, and chromaticities along the ramp, and measured transverse phase-advance at store. We also describe model improvements for derived observables like the quality of transverse bump closure and observed luminosity ratios between individual interaction points.  
 
TUPLT192 Transition Crossing for the BNL Super Neutrino Beam beam-losses, lattice, proton, 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.  
 
WEOACH01 High Field Gradient Cavity for J-PARC 3 GeV RCS impedance, beam-loading, acceleration, synchrotron 123
 
  • C. Ohmori, S. Anami, E. Ezura, K. Hara, Y. Hashimoto, A. Takagi, M. Toda, M. Yoshii
    KEK, Ibaraki
  • M. Nomura, A. Schnase, F. Tamura, M. Yamamoto
    JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  A new type of rf cavity will be used for J-PARC project. To minimize the beam loading effects, the quality factor of the core stack is increased by a cut core configuration. High power test of the rf system has been performed. Temperature rise around the cut surface of the cores were observed. It is minimized by improving the cooling efficiency.  
Video of talk
Transparencies
 
WEOACH02 Gas Condensates onto a LHC Type Cryogenic Vacuum System Subjected to Electron Cloud vacuum, electron, proton, synchrotron 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
 
WEOCCH01 A New 180 MeV H- Linac for Upgrades of ISIS linac, quadrupole, synchrotron, emittance 153
 
  • F. Gerigk
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  Several options have been studied to raise the beam power of the ISIS spallation neutron source to a level of 1 MW with the possibility of going to 4-5 MW in the longer term. All scenarios can operate in 2 modes, where the beam power is either delivered to a spallation target or, alternatively, to a target suitable to produce muons via pion decay for a neutrino factory. A more recent upgrade option takes an intermediate step and uses a 180 MeV H- linac, which is also foreseen for the 4-5 MW upgrade, as a replacement for the current 70 MeV injector. First estimates indicate that, due to the lower space charge forces, the ring would be able to carry twice as many particles, thus doubling the final beam power to 0.5 MW. This paper presents a first design for the 180 MeV linac, using a triple frequency jump from 234.8 to 704.4 MHz. The design profits from the development of 704.4 MHz cavities and RF equipment within the framework of the European HIPPI collaboration. The low frequency for the front-end was chosen to ease the DTL design as well as the development of a low energy beam chopper, which will be necessary to reduce beam losses at injection into the synchrotron.  
Video of talk
Transparencies
 
WEOCCH02 Construction Status and Issues of the Spallation Neutron Source Ring extraction, dipole, kicker, vacuum 156
 
  • J. Wei
    BNL, Upton, Long Island, New York
  (For the Spallation Neutron Source collaboration) The Spallation Neutron Source (SNS) accelerator complex is now in its sixth year of a seven-year construction cycle. The design, fabrication, test, and assembly of the accumulator ring and its transport lines is approaching the final stage. In order to reach the design goal of this high-power ring to deliver 1.5 MW beam power (1.5$× 1014 protons of 1 GeV kinetic energy at a repetition rate of 60 Hz), stringent measures have been implemented to ensure the quality of the accelerator systems. This paper reviews the progress of the ring and transport systems with emphasis on the challenging technical issues and their solutions inccurred during the construction period.  
Video of talk
Transparencies
 
WEODCH01 1.5-GeV FFAG Accelerator as Injector to the BNL-AGS acceleration, lattice, proton, 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
 
WEOALH03 Installation Strategy for the LHC Main Dipoles dipole, dynamic-aperture, multipole, resonance 176
 
  • S.D. Fartoukh
    CERN, Geneva
  All positions in the LHC machine are not equivalent in terms of beam requirements on the geometry and the field quality of the main dipoles. In the presence of slightly or strongly out-of tolerance magnets, a well-defined installation strategy will therefore contribute to preserve or even optimize the performance of the machine. In view of present state of the production, we have anticipated a list of potential issues (geometry, transfer function, field direction and random b3) which, combined by order of priority, have been taken into account to define a robust installation algorithm for the LHC main dipoles. Among the different possible strategies, the proposed one has been optimised in terms of simplicity and flexibility in order not to slow down and complicate the installation process. Its output is a prescription for installing the available dipoles in sequence while reducing to an absolute minimum the number of holes required by geometry or field quality issues.  
Video of talk
Transparencies
 
WEPKF006 Field Quality and Hysteresis of LHC Superconducting Corrector Magnets dipole, multipole, quadrupole, target 1600
 
  • A. Santrich Badal, M. Allitt, C. Giloux, M. Karppinen, A.M. Lombardi, V. Remondino, W.  Venturini Delsolaro, R. Wolf
    CERN, Geneva
  • M. Bagre, P. Khare, T. Maurya, A. Puntambekar
    CAT, Indore (M.P.)
  The Large Hadron Collider (LHC) will use some 6400 superconducting corrector magnets. There are 19 corrector types. These are assembled 14 different types of magnets of which 4 are nested. They are being manufactured by 4 firms in Europe and 3 in India. The magnetic field quality is measured at room temperature by 12 magnetic measurement benches employed by the corrector manufacturers. CERN performs magnetic measurement at 4.2K and at 1.9K on a small subset of corrector magnets. The paper discusses the correlation between the warm and cold field measurements. The field quality is compared to the magnet design expectations and to the target field quality for LHC. Many corrector circuits will be powered in a way which cannot be predicted before LHC will start operation and which even then may change between physics runs. The measured magnetic hysteresis and its influence on possible setting errors during operation is discussed, in particular for the orbit correctors and the tuning/trim quadrupole magnet circuits.  
 
WEPKF007 Vacuum Characterisation of a Woven Carbon Fiber Cryosorber in Presence of H2 vacuum, electron, scattering, collider 1603
 
  • V. Baglin, H. Dupont, T. Garcin
    CERN, Geneva
  Some of the cryogenic components in the Large Hadron Collider (LHC) will operate at 4.5 K. The H2 desorption will rapidly increase to the saturated vapour pressure, 3 orders of magnitude larger than the design pressure. Therefore, the use of cryosorbers is mandatory to provide the required pumping capacity and pumping speed. The behaviour of a woven carbon fiber to be used as a cryosorber has been studied under H2 injection. The pumping speed and capacity measured in the range 6 to 30 K are described. Observations made with an electron microscope are shown. A proposed pumping mechanism and the implications to the LHC are discussed.  
 
WEPKF008 A Strategy for Sampling of the Field Quality of the LHC Dipoles dipole, multipole, target, dynamic-aperture 1606
 
  • L. Bottura, S.D. Fartoukh, V. Granata, E. Todesco
    CERN, Geneva
  We have measured the magnetic field of a considerable fraction of the superconducting LHC main dipoles, of the order of 300 in warm conditions and 100 in cold conditions. All LHC dipoles will be measured in warm conditions at the manufacturers to steer the production inside the acceptance limits imposed by beam dynamics. Using the available data we analysed the distributions of the main field and higher order field errors in warm and cold conditions, as well as the distribution of the warm-to-cold correlation. Based on this analysis we predict the minimum number of magnets that should be measured in cold conditions in order to guarantee that (1) the production is controlled within the specified limits (2) the field is known to a sufficient level for a sound installation and (3) the uncertainty on the knowledge of the magnetic field of the LHC dipoles is small enough for the commissioning of the accelerator and to insure operation of the machine in any condition, including higher energy. The main outcome of this analysis is that cold measurements on a fraction of the order of one third of the total production, i.e. approximately 400 dipoles, will be sufficient to achieve the above objectives.  
 
WEPKF009 A Scaling Law for Predicting Snap-back in Superconducting Accelerator Magnets sextupole, dipole, multipole, magnet-design 1609
 
  • T. Pieloni, L. Bottura, S. Sanfilippo
    CERN, Geneva
  • G. Ambrosio, P. Bauer
    Fermilab, Batavia, Illinois
  • M. Haverkamp
    METROLAB, Plan-les-Ouates
  The decay of the sextupole component in the bending dipoles during injection and the subsequent snap-back at particle acceleration are issues of common concern, albeit at different levels of criticality, for all superconducting colliders built (Tevatron, HERA, RHIC) or in construction (LHC) to date. The main difficulty is the correction of the relatively large and fast sextupole change during snap-back. Motivated by the above considerations, we have conducted an extended study of sextupole snap-back on two different magnet families, the Tevatron and the LHC bending dipoles, using the same measurement method. We show in this paper that it is possible to generalise all the results obtained by using a simple, exponential scaling law. Furthermore, we show that for magnets of the same family the parameters of the scaling law correlate linearly. This finding could be exploited during accelerator operation to produce accurate forecast of the snap-back correction based solely on beam-based measurements.  
 
WEPKF014 Magnetic Field Tracking Experiments for LHC quadrupole, dipole, feedback, power-supply 1621
 
  • V. Granata, J. Billan, F. Bordry, L. Bottura, P. Coutinho Ferreira, E. Effinger, G. Fernqvist, P. Galbraith, Q. King, J. Pett, A. Raimondo, A. Rijllart, H. Thiesen
    CERN, Geneva
  At the Large Hadron Collider (LHC) at CERN one of the fundamental requirements during the energy ramp is that the ratio between the field produced by the quadrupoles and the field in the dipoles remains constant in order to minimize the variation of the betatron tune that could induce particle loss. With a series of tracking experiments it has been demonstrated that this ratio can be maintained constant to better than 10-4 throughout the same current ramp as foreseen for the LHC. A technique has been developed to optimise the dipole and quadrupole current ramps to obtain the required ratio of B2/B1. Measurements performed by modulating the current with a harmonic function (so-called k-modulation) demonstrated that it is possible to modulate the strength of an individual quadrupole to determine the magnetic center through beam-based measurements.  
 
WEPKF020 The Design of the Special Magnets for PIMMS/TERA septum, extraction, vacuum, power-supply 1639
 
  • L. Sermeus, J. Borburgh, T. Fowler, M. Hourican, K.D. Metzmacher
    CERN, Geneva
  • M. Crescenti
    TERA, Novara
  In the framework of a collaboration agreement with the TERA Foundation CERN provided the design, drawings and engineering specifications for 2 kickers, 1 chopper and 3 bumper magnets as well as 3 magnetic and 2 electrostatic septa, power supplies for the electrostatic septa, kickers and bumpers including control electronics for the PIMMS/TERA proton and carbon ion medical synchrotron. The first application will be in the Italian National Centre for Hadron Therapy, to be constructed in Pavia. The main features of the devices are described along with the strategic design choices, directed by the demand for very high reliability and minimum maintenance.  
 
WEPKF074 Magnetic Field Measurements of the LHC Inner Triplet Quadrupoles Produced at Fermilab quadrupole, alignment, interaction-region, dipole 1777
 
  • G. Velev, R. Bossert, R. Carcagno, J. DiMarco, S. Feher, H. Glass, V. Kashikhin, J.S. Kerby, M. Lamm, T. Nicol, L. Nobrega, D. Orris, T. Page, T. Peterson, R. Rabehl, P. Schlabach, J. Strait, C. Sylvester, M. Tartaglia, J. Tompkins, A.V. Zlobin
    Fermilab, Batavia, Illinois
  Production of 18 superconducting low-beta quadrupoles (MQXB) for the LHC is well advanced. These 5.5 m long magnets are designed to operate at 1.9 K with a peak field gradient of 215 T/m in the 70 mm apertures. Two MQXB cold masses with a dipole orbit corrector between them form a single cryogenic unit (LQXB) which is the Q2 optical element of the final focus triplets in the LHC interaction regions. A program of magnetic field quality and alignment measurements of the cold masses are performed at room temperature during magnet fabrication and LQXB assembly as well as at superfluid helium temperature. Results of these measurements are summarized in this paper.  
 
WEPKF075 Measurements of Sextupole Decay and Snapback in Tevatron Dipole Magnets sextupole, dipole, acceleration, superconductivity 1780
 
  • G. Velev, J. Annala, P. Bauer, J. DiMarco, H. Glass, R. Hanft, R. Kephart, M. Lamm, M. Martens, P. Schlabach, C. Sylvester, M. Tartaglia, J. Tompkins
    Fermilab, Batavia, Illinois
  To optimize the performance of the Fermilab Tevatron accelerator in Collider Run II, we have undertaken a systematic study of the drift and subsequent snapback of dipole magnet harmonics. The study has mostly focused on the dynamic behavior of the normal sextupole component, b2, as measured in a sample of spare Tevatron dipoles at the Fermilab Magnet Test Facility. We measured the dependence of the decay amplitude and the snapback time on Tevatron ramp parameters and magnet operational history. A series of beam studies was also performed [*]. This paper summarizes the magnetic measurement results and describes an optimization of the b2 correction scheme which is derived from these measurements.

* P.Bauer et al. These proceedings.

 
 
WEPKF079 A Kicker Design for the Rapid Transfer of the Electron Beam between Radiator Beamlines in LUX electron, septum, linac, kicker 1786
 
  • G.D. Stover
    LBNL/ALS, Berkeley, California
  I present in this paper preliminary design concepts for LUX - A ?fast kicker design for rapid transfer of the electron beam between radiator beamlines. This paper is a very simple feasibility study to find a rougly optimized subset of engineering parameters that would satisfy the initial design specifications of: Pulse width < 30us, time jitter < 1ns, magnetic length < 0.5meter, gap hight = 15mm, gap width = 25mm, peak field = .6Tesla, bend angle = 1.7 deg. for beam energy of 3.1 Gev, repetition rate = 10KHz. An H magnet core configuration was chosen. Through an iterative mathematical process a realizable design was chosen. Peak current, Peak voltages across the coils, conductor losses due to proximity and skin effects, di/dt rates, eddy and beam current heating in the ceramic vacuum chamber, and basic circuit topology were investigated. Types and losses of core material were only briefly discussed. The final topology consists of two magnets in series running at 10KHz, .3Tesla, 630 amp peak current, 10us pulse width, 364 Watts per coil section, driven by fast solid state switch with an energy recovery inductor. Eddy and beam image current losses were ~ 164 watts.  
 
WEPLT006 Expected Performance and Beam-based Optimization of the LHC Collimation System proton, collimation, 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.  
 
WEPLT008 Simulated Emittance Growth due to Electron Cloud for SPS and LHC emittance, electron, simulation, space-charge 1831
 
  • E. Benedetto, D. Schulte, F. Zimmermann
    CERN, Geneva
  • G. Rumolo
    GSI, Darmstadt
  The emittance growth caused by an electron cloud is simulated by the HEADTAIL code. The simulation result depends on the number of beam-cloud "interaction points"(IPs), the phase advance between the IPs, the number of macro-particles used to represent beam and cloud, and on the betatron tune. Simulations include a transverse feedback system and, optionally, a large chromaticity, as employed in actual SPS operation. Simulation results for the SPS are compared with observations, and the emittance growth in the LHC is computed as a function of the average electron density.  
 
WEPLT009 Dynamics of the Electron Pinch and Incoherent Tune Shift Induced by Electron Cloud electron, simulation, proton, 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, proton, emittance 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, proton, 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.  
 
WEPLT015 Proposal for the Creation and Storage of Long Bunches in the LHC luminosity, emittance, acceleration, hadron 1852
 
  • H. Damerau, R. Garoby
    CERN, Geneva
  Long bunches with a uniform longitudinal line density held by barrier buckets are considered for a future luminosity upgrade of the Large Hadron Collider (LHC). With such bunches, the luminosity is maximised for a fixed number of particles. Instead of conventional barrier buckets, periodic barriers are proposed. These are generated with multiple RF harmonics (e.g. multiples of 40 MHz). A possible scheme to create and hold long flat bunches in the LHC is described, and the resulting gain in luminosity is estimated.  
 
WEPLT017 Numerical Studies of the Impact of the Separation Dipoles and Insertion Quadrupoles Field Quality on the Dynamic Aperture of the CERN LHC quadrupole, dipole, insertion, multipole 1858
 
  • M. Giovannozzi, O.S. Brüning, S.D. Fartoukh, T. Risselada, F. Schmidt
    CERN, Geneva
  A wide range of magnets, both warm and superconducting, will be used in the LHC. In addition to main dipoles, quadrupoles are used to focus the beam in regular arcs. Special dipoles separate or merge the two beams in insertion regions. A few very strong superconducting quadrupoles squeeze the beam to achieve the required luminosity, while warm quadrupoles are used in the collimation insertions. At injection the main dipoles largely dominate beam dynamics, but contributions from smaller classes of magnets should not be neglected. Peculiar optical configurations may dramatically enhance beam dynamics effects of few magnetic elements. This paper will focus on the effect of insertion quadrupoles, e.g. wide-aperture, and warm quadrupoles, as well as separation dipoles presenting on the dynamic aperture of the LHC machine.  
 
WEPLT024 Scheduling the Installation of the LHC Injection Lines radiation, dipole, quadrupole, vacuum 1879
 
  • L. Lari, H. Gaillard, V. Mertens
    CERN, Geneva
  The installation of the two LHC injection lines has to fit within tight milestones of the LHC project and of CERN?s accelerator activity in general. For instance, the transfer line from the SPS to LHC point 8 (to fill the anti-clockwise LHC ring) should be tested with beam before the end of 2004 since the SPS will not run in 2005. It will first serve during the LHC sector test in 2006. Time constraints are also very strong on the installation of the transfer line from the SPS to LHC point 2 (for the clockwise LHC ring): its tunnel is the sole access for the LHC cryo-magnets and a large part of the beam line can only be installed once practically all LHC cryo-magnets are in place. Of course, the line must be operational when the LHC starts. This paper presents the various constraints and how they are taken into account for the logistics and installation planning of the LHC injection lines.  
 
WEPLT025 LHC Reference Database : Towards a Mechanical, Optical and Electrical Layout Database vacuum, collider, instrumentation, radio-frequency 1882
 
  • P. Le Roux, S. Chemli, A. Jimeno Yepes, B. Maire, H. Prin, A. Vergara-Fernández, M. Zerlauth
    CERN, Geneva
  The LHC project has entered a phase of integration and installation of thousands of diverse components. The Hardware Commissioning work has also started. Collecting and distributing reliable and coherent information on the equipments and their layout becomes a crucial requirement in the lifecycle of the project. Existing database tools had to evolve to a more generic model to cover not only optical layout, but also the mechanical and the electrical aspects. This paper explains the requirements, the implementation and the benefits of this new database model.  
 
WEPLT026 Dynamic Aperture Reduction from the Dodecapole Component in the LHC Main Quadrupoles and its Mechanism. dynamic-aperture, quadrupole, lattice, resonance 1885
 
  • A.M. Lombardi, O.S. Brüning, S.D. Fartoukh, T. Risselada, F. Schmidt, A. Verdier
    CERN, Geneva
  The systematic dodecapole component in the Main Quadrupoles of the LHC lattice has a strong influence on the machine dynamic aperture at injection. In this paper we quantify this effect with the help of tracking studies, explain the mechanism for the loss in dynamic aperture and look into potential correction schemes. Finally, we provide an estimate for the maximum allowed systematic dodecapole component in the MQ.  
 
WEPLT028 High-intensity and High-density Charge-exchange Injection Studies into the CERN PS Booster at Intermediate Energies simulation, space-charge, linac, emittance 1891
 
  • M. Martini
    CERN, Geneva
  • C.R. Prior
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  For the high brilliance LHC ultimate beam and the high intensity CNGS beam, single batch injections into the CERN Proton Synchrotron (PS) will be used to increase the overall machine intensity compared with the present double batch injections. Charge-exchange injection into the PS Booster with a new linac at intermediate energies is thus examined. A key parameter to consider is the energy dependence of beam incoherent tune shifts at injection. Increasing the linac energy from the present 50 MeV to 160 MeV should yield a safer tune shift. For each PS Booster ring, a charge-exchange injection scheme is envisaged inside a proper straight section, redesigned with new bends to make a local bump and using the existing fast bump magnets for horizontal phase-space painting. ACCSIM simulations for charge-exchange injection at 160 MeV have been investigated for both LHC and CNGS beams. After optimizing the parameters that are used for the space charge tracking routines, the results of the simulations agree well with expectations, signifying that the LHC ultimate and CNGS beams may be provided with single PS Booster batches within the required emittances. For assessment, simulation of injection at 50 MeV for the current LHC beam has been performed, yielding a fairly good agreement with measured performance. Concurrently, similar charge-exchange injection simulations have been carried out using an alternative programme developed at the Rutherford Appleton Laboratory.  
 
WEPLT029 Intensity Dependent Emittance Transfer Studies at the CERN Proton Synchrotron emittance, simulation, resonance, synchrotron 1894
 
  • E. Métral, C. Carli, M. Giovannozzi, M. Martini, R.R. Steerenberg
    CERN, Geneva
  • G. Franchetti, I. Hofmann
    GSI, Darmstadt
  • J. Qiang
    LBNL, Berkeley, California
  • R.D. Ryne
    LBNL/CBP, Berkeley, California
  An intensive study has been undertaken since the year 2002 to understand better the various high-intensity bottlenecks of the CERN Proton Synchrotron machine. One of these limitations comes from the so-called Montague resonance. High-intensity proton synchrotrons, having larger horizontal than vertical emittance, may suffer from this fourth-order coupling resonance driven by space charge only. In particular, such resonance may lead to emittance sharing and, possibly, beam loss due to vertical acceptance limitation. Experimental observations made in the 2002 and 2003 runs on the Montague resonance are presented in this paper and compared with 3D particle-in-cell simulation results and theoretical predictions.  
 
WEPLT030 Stability Diagrams for Landau Damping with Two-dimensional Betatron Tune Spread from Both Octupoles and Non-linear Space Charge applied to the LHC at Injection space-charge, octupole, betatron, damping 1897
 
  • E. Métral, F. Ruggiero
    CERN, Geneva
  The joint effect of space-charge non-linearities and octupole lenses is discussed for the case of a quasi-parabolic transverse distribution of a monochromatic beam. The self-consistent non-linear space-charge tune shift corresponding to the above distribution function is first derived analytically. The exact dispersion relation is also given but not solved. Instead, noting that a good approximation of the non-linear space-charge tune shift is obtained considering only linear terms in the action variables, the dispersion relation is solved analytically in this approximate case. As expected, in the absence of external (octupolar) non-linearities, the result of Möhl and Schönauer is recovered: there is no stability region. In the absence of space charge, the stability diagrams of Berg and Ruggiero are also recovered. Finally, the new result is applied to the LHC at injection.  
 
WEPLT031 The LHC Access Control System site, man-machine-interface 1900
 
  • P. Ninin, L. Scibile
    CERN, Geneva
  The LHC complex is divided into a number of zones with different levels of access controls. Inside the interlocked areas, the personnel protection is ensured by the LHC Access System. This system is made of two parts: the LHC Access Safety System and the LHC Access Control System. During machine operation, the LHC Access Safety System ensures the collective protection of the personnel against the hazards arising from the operation of the accelerator. By interlocking the LHC key safety elements, it will permit access to authorised personnel in the underground premises during the accelerator shutdowns and will deny access during accelerator operation. On the other hand, the LHC Access Control System, regulates the access to the accelerator and the numerous support systems. It allows a remote, local or automatic operation of the access control equipment that verifies the users? authorization, identifies them, locks and unlocks access control equipment and restricts the number of users working simultaneously in the interlocked areas. This paper introduces the main functions, architecture, technologies and methodology used to realise the LHC Access system.  
 
WEPLT035 Capture Loss of the LHC Beam in the CERN SPS beam-losses, impedance, feedback, simulation 1906
 
  • E.N. Shaposhnikova, T. Bohl, T.P.R. Linnecar, J. Tuckmantel
    CERN, Geneva
  The matched voltage of the LHC beam at injection into the SPS is 750 kV. However, even with RF feedback and feed forward systems in operation, the relative particle losses on the flat bottom for nominal LHC parameters with this capture voltage can reach the 30% level. With voltages as high as 2 MV these losses are still around 15% pushing the intensity in the SPS injectors to the limit to obtain nominal intensity beam for the LHC. Beam losses grow with intensity and are always asymmetric in energy (lost particles are seen main in front of the batch). The asymmetry can be explained by the energy loss of particles due to the SPS impedance which is also responsible for a non-zero synchronous phase on the flat bottom leading to large gaps between buckets. In this paper the measurements of the dependence of particles loss on the beam and machine parameters are presented and discussed together with possible loss mechanisms.  
 
WEPLT038 Betatron Resonance Studies at the CERN PS Booster by Harmonic Analysis of Turn-by-turn Beam Position Data resonance, booster, coupling, simulation 1915
 
  • P. Urschütz, M. Benedikt, C. Carli, M. Chanel, F. Schmidt
    CERN, Geneva
  High brightness and high intensity beams are required from the PS Booster for LHC, CNGS and ISOLDE operation. The large space charge tune spreads associated with these beams, especially at injection, require an optimized resonance compensation scheme to avoid beam blow-up and subsequent beam losses. For this a detailed knowledge on strength and phase of resonance driving terms is needed. A new measurement system has been installed to determine resonance driving terms from turn-by-turn bpm data using fast Fourier transform. The multi-turn acquisition system as well as the specific measurement conditions at the PS Booster are discussed. As an example, the measurement and compensation of the linear coupling resonance driving term is presented. Excellent agreement between measurement and simulation for resonance phase and strength was found.  
 
WEPLT039 Measurement and Compensation of Second and Third Order Resonances at the CERN PS Booster resonance, booster, sextupole, coupling 1918
 
  • P. Urschütz
    CERN, Geneva
  Space charge effects at injection are the most limiting factor for the production of high brightness beams in the CERN PS Booster. The beams for LHC, CNGS and ISOLDE feature incoherent tune spreads exceeding 0.5 at injection energy and thus cover a large area in the tune diagram. Consequently these beams experience the effects of transverse betatron resonances and efficient compensation is required. Several measurements have been performed at the PS Booster in 2003, aiming at a detailed analysis of all relevant second and third order resonances and an optimisation of the compensation scheme. Special attention was paid to the systematic 3Qy=16 resonance. To avoid this particularly dangerous resonance an alternative working point was tested. A comparison of resonance driving terms and compensation settings for both working points was made and important differences in the strengths of the resonances were found. The peculiarities when measuring third order coupling resonance driving terms are also mentioned.  
 
WEPLT042 Scheduling the Installation of the Large Hadron Collider site, civil-engineering, feedback, extraction 1927
 
  • S. Weisz, K. Foraz, H. Gaillard, L. Lari
    CERN, Geneva
  The size and complexity of the LHC project at CERN calls for a strong co-ordination of all installation activities. The detailed installation planning has to take into account many constraints such as the component production rates, the installation contracts or the transport and handling requirements in a narrow tunnel with limited access points. The planning also needs to be flexible enough to cope with aleas that are unavoidable in such a large project that spans over many years. This paper describes the methodology followed by the team responsible for the planning and logistics in order to stay reactive to the actual progress of the installation and to keep optimizing the usage of resources.  
 
WEPLT044 Electron-cloud Build-up Simulations and Experiments at CERN electron, simulation, vacuum, quadrupole 1933
 
  • F. Zimmermann, G. Arduini, V. Baglin, T. Bohl, B.J. Jenninger, J.M. Jimenez, J.-M. Laurent, F. Ruggiero, D. Schulte
    CERN, Geneva
  We compare the predications of electron-cloud build-up simulations with measurements at the CERN SPS. Specifically, we compare the electron flux at the wall, electron-energy spectra, heat loads, and the spatial distribution of the electrons for two different bunch spacings, with variable magnetic fields, and for several chamber temperatures and associated surface conditions. The simulations employ a modified, improved version of the ECLOUD code. The main changes are briefly described. We finally present updated simulation results for the heat load in the cold LHC arcs.  
 
WEPLT082 General Performances of the Injection Scheme into the SOLEIL Storage Ring septum, coupling, undulator, quadrupole 2044
 
  • M.-A. Tordeux, J. Da Silva, P. Feret, P. Gros, P. Lebasque, A. Mary
    SOLEIL, Gif-sur-Yvette
  The injection scheme of the electron beam into the Storage Ring of the SOLEIL synchrotron is presented. It corresponds to the new SOLEIL optics : 12 meter long straight section, 2.75 GeV energy, with in addition the requirement for top-up injection mode. Pulsed magnets are described, and in particular the passive septum magnet, the transverse position of which can be adjusted so as to optimise the Touschek beam Lifetime. Tracking of particles has been performed over a large number of turns, taking into account the magnet errors, the high chromaticities and the physical apertures all along the machine (limited vertical apertures due to low gap undulators). Statistical efficiency of the injection has been deduced. Specific requirements for top-up injection have been examined, such as the closure of the injection bump, the residual vertical field and the leakage fields from septa.  
 
WEPLT093 Electromagnetic Fields of an Off-axis Bunch in a Circular Pipe with Finite Conductivity and Thickness - I multipole, vacuum, single-bunch, electromagnetic-fields 2068
 
  • S. Petracca, L. Cappetta, T. Demma
    U. Sannio, Benevento
  The electromagnetic field produced by a bunched beam in a circular pipe is usually computed under the assumption that the field penetration(skin depth) is far less than the wall thickness. Chao [*] gave a formula which exploits the wall thickness, but his result is restricted to the monopole term. Piwinski [**] treated the case of a metal coated ceramic wall, when the coating thickness is much smaller than the skin-depth, but his analysis is also limited to the monopole term.In this paper we solve the problem in full generality, by providing an exact (Green's functions) solution for the field of an off-axis point particle running at constant velocity in a circular pipe with finite wall conductivity and thickness.

* A.W. Chao, Phys. of Collective Beam Instab. in High En. Accel., Wiley,1993** S. Piwinski, DESY 1972/72

 
 
WEPLT097 Beam Loading in the RF Deflector of the CTF3 Delay Loop beam-loading, emittance, linac, simulation 2077
 
  • D. Alesini, F. Marcellini
    INFN/LNF, Frascati (Roma)
  In this paper we describe the impact of the beam loading in the RF deflectors on the transverse beam dynamics of the CTF3 Delay Loop. The general expression for the single passage wake field is obtained. A dedicated tracking code has been written to study the multi-bunch multi-turn effects on the transverse beam dynamics. A complete analysis for different machine parameters and injection errors is presented and discussed. The numerical simulations show that the beam emittance growth due to the wake field in the RF deflectors is small.  
 
WEPLT100 Planar Electron Sources and the Electron Trap ELTRAP electron, cathode, plasma, laser 2083
 
  • M. Cavenago
    INFN/LNL, Legnaro, Padova
  • G. Bettega, F. Cavaliere, A. Illiberi, R. Pozzoli, M. Romé, L. Serafini
    INFN-Milano, Milano
  Filamentation and other space charge effects (both transverse and longitudinal) of intense electron beams, found for example in rf photoinjectors (beam energy 1 MeV, current 100 A), are easily studied in small voltage traps and drift channels (0.01-10 kV), keeping the same perveance order. A suitable Malmberg-Penning trap, named ELTRAP, installed and operated at the University of Milan, is briefly described; trap length ranges from 10 cm to 1 m; an uniform magnetic field confines electron radially. Several experimental regimes were investigated with the internal CW planar electron source: plasma, beam-plasma, beam, depending on the injection/extraction method chosen. Evolution of electron vortices and virtual cathode formation is documented; analogy with meteorologic and astrophysical plasma is discussed. Upgrading with an external laser pulsed electron source is in course. Larger planar sources are also under construction. (Main classification 4: Beam Dynamics and Electro-magnetic Fields; D03 High Intensity, Incoherent Instabilities, Space Charge, Halos, Cooling; Other classification 8: Low and Intermediate Energy Accelerators and Sources; T12 Beam Injection/Extraction and Transport; T02 Lepton sources)  
 
WEPLT101 On-line Mechanical Instabilities Measurements and Tuner Development in SC Low-beta Resonators linac, feedback, vacuum, resonance 2086
 
  • A. Facco, E. Bissiato, S. Canella, D. Carlucci, M. Lollo, F. Scarpa, D. Zenere
    INFN/LNL, Legnaro, Padova
  The use of high-Q and small rf bandwidth superconducting quarter wave resonators made of bulk niobium put severe requirements to the helium bath pressure stability to avoid cavity detuning. This is not always possible, and cavity detuning caused by slow pressure changes must be precisely followed by the cavity tuner. The LNL philosophy is based on mechanical damping of cavity vibrations and mechanical tuning in feedback for slow frequency compensation. The old-fashioned tuners installed in the ALPI linac had significant performance limitations. To replace them, we have designed, constructed and tested a new tuner which integrates the LNL system and control with the TRIUMF, backlash-free tuner leverage design. The new tuner is designed to compensate pressure changes up to 100 mbar/minute with a precision of 0.5 Hz, and it will be installed in the ALPI resonators. An upgraded prototype for future applications includes a piezoelectric actuator for fast tuning. Tuner characteristics and first test results will be presented. This system is extendable to other low-beta cavity types like superconducting rfqs.  
 
WEPLT102 Electron Cooling Experiments at HIMAC Synchrotron ion, simulation, electron, heavy-ion 2089
 
  • K. Noda, T. Furukawa, T. Honma, S. Shibuya, D. Tan, T. Uesugi
    NIRS, Chiba-shi
  • T. Iwashima
    AEC, Chiba
  • I.N. Meshkov, E. Syresin
    JINR, Dubna, Moscow Region
  • S. Ninomiya
    RCNP, Osaka
  In the HIMAC synchrotron, the electron cooling experiments have been carried out since 2000 in order to develop new technologies in heavy-ion therapy and related research. Among of them, especially, the cool-stacking method has been studied to increase the intensity of heavy ions such as Fe and Ni in order to study the risk estimation of the radiation exposure in space. The simulation was carried out in order to optimize the stacking intensity under various the injection periods. In addition, the beam heating by the RF-KO and the clearing the secondary ion in the cooler were applied to avoid the instability occurred when the beam density became high. We will report the experiment results.  
 
WEPLT107 Nonlinear field Effects in the JPARC Main Ring resonance, sextupole, betatron, space-charge 2101
 
  • A.Y. Molodojentsev, S. Machida, Y. Mori
    KEK, Ibaraki
  Main Ring (MR) of the Japanese Particle Accelerator Research Complex (JPARC) should provide acceleration of the high-intensity proton beam from the energy of 3GeV to 50 GeV. The expected beam intensity is 3.3·1014 ppp and the repetition rate is about 0.3 Hz. The imaginary transition lattice of the ring was adopted, which has the natural linear chromaticity about (-30) for both transverse phase planes. The expected momentum spread of the captured particles before the acceleration is less than 0.007. Two independent families of the chromatic sextupole magnets are use to eliminate the linear chromatic tune shift. This chromatic sextupole field nonlinearity will excite the normal 'octupole' resonances and will lead to the amplitude dependent tune shifts in both transverse phase planes. Additional sextupole magnets are planed to excite the third-order horizontal resonance, which will be used for the slow extraction. Incoherent tune shift of the low-energy proton beam is about (-0.16) so that some particles could cross nearest low-order resonances. Optimization of the 'bare' working point of MR at the injection energy has been performed to minimize the influence of the linear coupling and high-order coupling resonances. Excitation of the linear coupling resonance has been introduced by the realistic misalignment errors adopted for MR. The 'bare' working point during the slow extraction has been analyzed. The influence of the normal sextupole resonances on the large amplitude particle behavior at the scraper location has been studied including random sextupole field component of the MR bending magnets. Realistic distortion of the ideal ring super-periodicity by the injection kicker magnets has been included in the tracking procedure for the on- and off-momentum particles. Finally, correction schemes have been considered for most dangerous resonances around the optimized 'bare' working point. The space-charge effects of the proton beam have not been included in this study.  
 
WEPLT153 Multi-pass Beam-breakup: Theory and Calculation linac, simulation, recirculation, damping 2197
 
  • I. Bazarov
    Cornell University, Department of Physics, Ithaca, New York
  • G. Hoffstaetter
    Cornell University, Laboratory for Elementary-Particle Physics, Ithaca, New York
  Multi-pass, multi-bunch beam-breakup (BBU) has been long known to be a potential limiting factor for the current in linac-based recirculating accelerators. New understanding of theoretical and computational aspects of the phenomenon are presented here. We also describe a detailed simulation study of BBU in the proposed 5 GeV Energy Recovery Linac light source at Cornell University which is presented in a separate contribution to this conference.  
 
WEPLT169 Benchmark and Threshold Analysis of Longitudinal Microwave Instability in the PSR space-charge, impedance, proton, 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.  
 
WEPLT170 Injection Schemes for Self Consistent Space Charge Distributions space-charge, closed-orbit, vacuum, betatron 2227
 
  • V.V. Danilov, S.M. Cousineau, S. Henderson, J.A. Holmes, M. Plum
    ORNL/SNS, Oak Ridge, Tennessee
  This paper is based on recently found sets of self-consistent 2D and 3D time-dependent space charge distributions. A subset of these distributions can be injection-painted into an accumulator ring, such as Spallation Neutron Source Ring, to produce periodic space charge conditions. The periodic condition guarantees zero space-charge-induced halo growth and beam loss during injection. Practical aspects of such schemes are discussed, and simulations of a few specific cases are presented.  
 
WEPLT177 Analysis of Electron Cloud at RHIC electron, proton, 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.  
 
THOACH02 Commissioning of the 500 MeV Injector for MAX-lab linac, gun, electron, storage-ring 219
 
  • S. Werin, Å. Andersson, M. Bergqvist, M. Brandin, M. Demirkan, M. Eriksson, L.-J. Lindgren, L. Malmgren, H. Tarawneh, E.J. Wallén
    MAX-lab, Lund
  • B. Anderberg
    AMACC, Uppsala
  • G. Georgsson
    Danfysik A/S, Jyllinge
  • G. LeBlanc
    ASP, Melbourne
  A 500 MeV new injector system for the storage rings MAX I, II and III have been installed during the winter 2003-4 at MAX-lab. The system consists of two linacs at 125 MeV each, using SLED, and a recirculating system such that the electrons pass the linacs twice, thus reaching a final energy of 500 MeV. The system is injected by a thermionic RF-gun. The commissioning of the complete system will be performed in the spring 2004.  
Video of talk
Transparencies
 
THOACH03 Top-up Operation at SPring-8 - Towards Maximizing the Potential of a 3rd Generation Light Source storage-ring, target, beam-losses, single-bunch 222
 
  • H. Tanaka, T. Aoki, T. Asaka, S. Daté, K. Fukami, Y. Furukawa, H. Hanaki, N. Hosoda, T. Kobayashi, N. Kumagai, M. Masaki, T. Masuda, S. Matsui, A. Mizuno, T. Nakamura, T. Nakatani, T. Noda, T. Ohata, H. Ohkuma, T. Ohshima, M. Oishi, S. Sasaki, J. Schimizu, M. Shoji, K. Soutome, M. Suzuki, S. Suzuki, S. Takano, M. Takao, T. Takashima, H. Takebe, K. Tamura, R. Tanaka, T. Taniuchi, Y. Taniuchi, K. Tsumaki, A. Yamashita, K. Yanagida, H. Yonehara, T. Yorita
    JASRI/SPring-8, Hyogo
  • M. Adachi, K. Kobayashi, M. Yoshioka
    SES, Hyogo-pref.
  Top-up operation maximizes research activities in a light source facility by an infinite beam lifetime and photon beam stability. We have been improving the SPring-8 accelerators to achieve the ideal top-up operation. For the perturbation-free injection, we adjusted the magnetic field shape of four bump magnets to close the bump orbit, and introduced a scheme to suppress the stored beam oscillation induced by the nonlinearlity of sextupole magnets. These reduced the horizontal oscillation down to a third of the stored beam size. For the loss-free injection, beam collimators were installed upstream of the injection line. This realized the injection efficiency of ~100% under the restricted gap condition of in-vacuum insertion devices (ID). Since autumn 2003, we have been injecting the beams keeping the photon beam shutters opened and ID gaps closed. We developed a bunch-by-bunch feedback system to reduce the beam loss further with all the ID gaps fully closed by lowering the operating chromaticity. The operation with constant stored current is scheduled in June 2004. We present the overview and progress of the SPring-8 top-up operation focusing on our developments and results.  
Video of talk
Transparencies
 
THOBCH01 The Beijing Electron-positron Collider and its Second Phase Construction luminosity, synchrotron, synchrotron-radiation, vacuum 230
 
  • C. Zhang, J.Q. Wang
    IHEP Beijing, Beijing
  The Beijing Electron-Positron Collider (BEPC) was constructed for both high energy physics and synchrotron radiation researches. As an e+ e- collider operating in the tau-charm region and a first synchrotron radiation source in China, the machine has been well operated for 14 years since it was put into operation in 1989. As a collider, the peak luminosity of the BEPC has reached its design goal of 5*1030 cm-2s-1 at J/sai energy of 1.55 GeV and 1*1031 cm-2s-1 at 2 GeV respectively. The main parameters in the dedicated synchrotron radiation operation are: E=2.2~2.5 GeV, ex0=80 mm mrad at 2.2 GeV, Ib=140 mA and the beam lifetime of 20~30 hours. As the second phase project of the BEPC, the BEPCII , has been approved with total budget of 640 million RMB. The construction is started in the beginning of 2004 and is scheduled to complete by the end of 2007. The BEPCII is a double ring machine with its luminosity goal of 1*1033 cm-2s-1 at 1.89 GeV, two orders of magnitude higher than present BEPC. The BEPCII will operate in the beam energy of 1-2.1 GeV so that its physical potential in the whole t and charm range is preserved, while the collider will be optimized at 1.89 GeV. The upgrading of the collider should also provide an improved SR performance with higher beam energy and intensity. The beam currents will be increased to 250 mA at E=2.5 GeV for the dedicated synchrotron radiation operation of the BEPCII. Some key technologies, such as superconducting RF system, low impedance vacuum devices, superconducting micro-beta quadrupoles and etc., has been intensively studied in order to achieve the target of the BEPCII.  
Video of talk
Transparencies
 
THPKF004 The Australian Synchrotron Project - Update synchrotron, storage-ring, site, insertion 2260
 
  • A. Jackson
    ASP, Melbourne
  The Australian Synchrotron - a 3rd generation synchrotron light facility based on a 3-GeV electron storage ring - is under construction at a site adjacent to Monash University in the Metropolitan District of Melbourne. Site preparation started in September 2003 and project completion is scheduled for March 2007. In this paper we present an overview of the facility and discuss progress to date in meeting this very agressive schedule.  
 
THPKF005 The Australian Synchrotron Project Storage Ring and Injection System Overview storage-ring, synchrotron, lattice, dipole 2263
 
  • G. LeBlanc, M.J. Boland, Y.E. Tan
    ASP, Melbourne
  This paper describes the Australian Synchrotron storage ring. The storage ring is a 3 GeV machine with 14 cells and a circumference of 216 m. The unit cell is based on a Double Bend Achromat (DBA) structure. The design of the magnet lattice and the results of simulations pertaining to the storage ring performance are presented.  
 
THPKF007 Canadian Light Source Status and Commissioning Results quadrupole, storage-ring, dipole, sextupole 2269
 
  • L. Dallin, R. Berg, J.C. Bergstrom, X. Shen, R.M. Silzer, J.M. Vogt, M.S. de Jong
    CLS, Saskatoon, Saskatchewan
  The storage ring for the Canadian Light Source (CLS) was completed in August 2003. By January 2004, after about shifts of commissioning beam currents of up to 25 mA with 0.7 hr lifetimes were achieved. Injection times for 25 mA are about 4 minutes. Commissioning activities include global orbit correction, measurement of machine parameters and beam-based diagnostices. Features of the CLS are a compact lattice (170 m) for a 2.9 GeV storage ring, high performance magnets and a superconducting RF cavity. By July, when beamlines become operational, currents up to 100 mA with 4 hour lifetimes are expected.  
 
THPKF008 Injection System for the Canadian Light Source storage-ring, booster, linac, septum 2272
 
  • R.M. Silzer, R. Berg, J.C. Bergstrom, L. Dallin, X. Shen, J.M. Vogt
    CLS, Saskatoon, Saskatchewan
  The full energy injection system for the Canadian Light Source is made up of a 250 MeV linac, a low energy transfer line, a 2.9 GeV booster synchrotron and a high energy transfer line. The system has routinely provided up to 25 mA peak current in a 132 ns pulse train to the CLS storage ring injection point since September 2003. By January, 2004, injection efficiencies up to 10% have been acheived and stored currents up to 25 mA were accumulated in less than 4 minutes. The injection timing system allows a variety of fill patterns. By July, 2004, injection rates of up to 2 mA per second should be possible providing a fill time of under one minute for a 100 mA stored beam.  
 
THPKF009 Orbit Control for the Canadian Light Source feedback, storage-ring, power-supply, booster 2275
 
  • R. Berg, L. Dallin, J.M. Vogt
    CLS, Saskatoon, Saskatchewan
  The orbit control system for the Canadian Light Source storage ring is design to provide both static global orbit correction and active correction up to 100 Hz. The system is made up of 48 button monitors (X and Y), 24 fast correcter magnets (X and Y), and 24 slow correction coils in sextupole magnets (X and Y). To date the system has been use to apply static corrections the to CLS storage ring. While some works remains on the horizontal correction, the vertical orbit has been corrected to an RMS value of less tha 0.75 mm. Future corrections may be augmented by some beam-based magnet re-alignment. The orbit correction system is run on a MATLAB(R) operating system. Singular value decompostion (svd) was used extensively to reduce initial gross mis-alignments.  
 
THPKF012 Operation of the Swiss Light Source: Top-up for Highest Performance linac, booster, feedback, beam-losses 2281
 
  • A. Lüdeke
    PSI, Villigen
  The Swiss Light Source (SLS) is now in its third year of user operation. Right from the beginning Top-up has been the standard mode of operation. Operation at a fixed beam current makes many applications easier to implement and allows to push several systems to higher performance. It enabled us to reach an excellent orbit stability and reproducibility and it made our users less sensitive to shortened beam lifetimes. We succeeded to satisfy the high demands on the availability of the injector system and our flexible timing system allows for a parallel usage of the Linac for experiments during Top-up operation. The impact of Top-up operation on the overall performance of the SLS is documented in this paper.  
 
THPKF017 Status of the Synchrotron Light Source DELTA synchrotron, feedback, vacuum, radiation 2296
 
  • D. Schirmer, U. Berges, J. Friedl, A. Gasper, M. Grewe, P. Hartmann, R.G. Heine, H. Huck, G. Schmidt, C. Sternemann, M. Tolan, T. Weis, C. Westphal, K. Wille
    DELTA, Dortmund
  Since 1999, the Dortmunder 1.5 GeV electron storage ring DELTA was continuously extended. The facility serves universities and industries as a source of synchrotron radiation on a regional level. The consolidation of the machine was finally completed in 2002. By now, DELTA, operated for 3000 hours per year, has reached a reliability comparable to other facilities in the world. Large improvements have been made in the installation of the beamlines. At present, two undulator beamlines and several dipole beamlines in the range of soft X-rays are in operation. The 5.3 T superconducting asymmetric wiggler (SAW) serves three beamlines in the hard X-ray regime with circular polarized light. Also the accelerator physics research program has been promoted. The vacuum system was revised during the last year to provide extra space for test sections and additional diagnostics. Substantial progress was achieved by SVD based orbit correction and LOCO based optics modelling as well as detailed CBM studies and a new method for fast tune measurements has been implemented. Future developments for machine improvements, such as DSP-based fast local orbit feedback and a frequent injection mode are in preparation.  
 
THPKF018 Study for a Frequent Injection Mode at Delta with Beam Shutters Open radiation, storage-ring, feedback, synchrotron 2299
 
  • G. Schmidt, M. Benna, U. Berges, J. Friedl, A. Gasper, M. Grewe, P. Hartmann, R.G. Heine, H. Huck, D. Schirmer, S. Strecker, T. Weis, K. Wille, N. Zebralla
    DELTA, Dortmund
  The Dortmunder Electron Accelerator (DELTA) is a 1.5 GeV synchrotron light source. DELTA is now operated for 3000 h per year including 2000 h beam time for synchrotron radiation use. The maximum beam current is limited by rf power. To increase the average beam current a frequent injection scheme with beam shutters open is discussed for Delta. The peak current is not enlarged but the number of injections is increased to establish a quasi constant beam current. The quasi constant beam current has in addition the advantage of a constant synchrotron radiation heat-load on vacuum chambers and experiments. First tests at Delta have shown the gain in stability of the closed orbit during frequent injection. This article shows the possibility to install a frequent injection mode with beam shutters open during injection at DELTA. The results of measurements and simulations are presented.  
 
THPKF023 Studies using Beam Loss Monitors at ANKA beam-losses, vacuum, electron, storage-ring 2314
 
  • F. Pérez, I. Birkel, K. Hertkorn, E. Huttel, A.-S. Müller, M. Pont
    FZK-ISS-ANKA, Karlsruhe
  ANKA is a synchrotron light source that operates in the energy range from 0.5 to 2.5 GeV. In order to investigate the electron beam losses, two kind of beam loss monitors have been installed: 24 Pin Diode from Bergoz distributed around the storage ring, and one Pb-glass calorimeter located in a high dispersion region. The Pin Diodes are used to obtain information about the distribution of the losses while the Pb-glass detector provides higher sensitivity. The Pin Diodes allow to locate and distinguish the regions of higher losses due to Touschek and Elastic scattering. Furthermore, regions of higher losses at injection have been identified. The Pb-glass detector has been used to determine the beam energy with the resonant spin depolarisation technique. A strong spin orbit resonance has been observed with both detectors.  
 
THPKF024 A STATE-OF-THE-ART 3 GEV BOOSTER FOR ASP booster, septum, lattice, sextupole 2317
 
  • G. Georgsson, N. Hauge
    Danfysik A/S, Jyllinge
  • S.P. Møller
    ISA, Aarhus
  DANFYSIK A/S will build the full-energy booster for the Australian Synchrotron Project. The Booster will accelerate the beam from the injection energy of 100 MeV to a maximum of 3.0 GeV. The Booster shall accelerate either a single bunch or a bunch train up to 150 ns. The current accelerated to 3 GeV will be in excess of 0.5 and 5 mA for the two modes, respectively. The circumference of the Booster is 130.2 m, and the lattice will have four-fold super-symmetry with four straight sections for RF, injection, special diagnostics and extraction. The lattice is designed to have many cells with combined-function magnets (dipole, quadrupole and sextupole fields) in order to reach a very small emittance of around 30 nmrad. A small emittance is beneficial, in particular for top-up operation. Details of the lattice design and beam dynamics of the booster will be presented.  
 
THPKF025 Commissioning Report of the CLS Booster Synchrotron booster, synchrotron, beam-losses, lattice 2320
 
  • G. Georgsson
    Danfysik A/S, Jyllinge
  • L. Dallin
    CLS, Saskatoon, Saskatchewan
  • S.P. Møller
    ISA, Aarhus
  • L. Præstegaard
    Århus Sygehus, Århus
  A full energy booster is produced and taken into operation for the Canadian Light Source. The Booster accelerates the beam from the injection energy of 200 MeV to a maximum of 2.9GeV. The results of the commissioning and the characterized beam parameters are reported  
 
THPKF032 Cleaning of Parastic Bunches in the ESRF Booster Synchrotron for Time Structure Modes of Operation booster, acceleration, synchrotron, betatron 2341
 
  • E. Plouviez, N. Michel
    ESRF, Grenoble
  The ESRF injector booster accelerates electron bunches from 200 MeV to 6 GeV and inject them in a storage ring. It can accelerate a small number (1 to 5) of high charge bunches for the so called "time structure" filling mode operation of the SR. In this case we must avoid storing parasitic low charge bunches in the unused RF bucket of the SR. Until now this was achieved by a resonant knockout of these parasitic bunches on the beam stored in the SR. We have developed and implemented a system allowing the removal of these parasitic electrons during the acceleration in the booster, so that no extra cleaning is needed on the beam stored in the SR. This paper describes our setup and its key components, the tuning of the operating parameters of the system and presents the results achieved.  
 
THPKF035 Design of the Super-SOR Light Source synchrotron, storage-ring, linac, optics 2350
 
  • N. Nakamura
    ISSP/SRL, Chiba
  The Super-SOR light source is a Japanese VUV and soft X-ray third-generation synchrotron radiation source, which is to be operated for nation-wide and world-wide users. The University of Tokyo has proposed to construct the facility in Kashiwa new campus and we have designed the light source intensively for more than two years. The light source consists of an electron storage ring, booster synchrotron and pre-injector linac. The 1.8-GeV storage ring has a circumference of about 280 m and 14 DBA cells with two 17-m and twelve 6.2-m long straight sections, which are used for twelve insertion devices and RF and injection systems. The booster synchrotron is compact, one third of the ring in circumference, and can achieve a low emittance of about 50 nmrad at 1.8 GeV. The 200-MeV linac is made up of S-band accelerating structures powered by two 50-MW klystrons and a SLED cavity and capable of changing the beam current widely in both single- and multi-bunch operation modes. These accelerators are designed so as to fully meet requirements for top-up injection. We describe the design of the Super-SOR accelerators here.

on behalf of the Super-SOR accelerator design group

 
 
THPKF039 Study of Photo-cathode RF Gun for a High Brightness Electron Beam gun, cathode, laser, electron 2362
 
  • Y. Yamazaki
    JNC/OEC, Ibaraki-ken
  • S. Araki, H. Hayano, M. Kuriki, T. Muto, N. Terunuma, J. Urakawa
    KEK, Ibaraki
  • M.K. Fukuda, K. Hirano, M. Nomura, M. Takano
    NIRS, Chiba-shi
  We are going to develop a compact high-brightness electron beam system to adopt industrial and medical applications. A multi-bunch photo-cathode RF gun has been developed to generate 100 bunches beam with 2.8ns spacing and 5nC charge per bunch. We will report details of the development, especially photo-cathode production and emission characteristics from cathode by the laser.  
 
THPKF041 SSRF: A 3.5GeV Synchrotron Light Source for China storage-ring, booster, synchrotron, undulator 2368
 
  • Z. Zhao, H. Xu
    SINR, Jiading, Shanghai
  The Shanghai Synchrotron Radiation Facility (SSRF) is an intermediate energy light source that will be built at Zhang-Jiang Hi-Tech Park in Shanghai. The SSRF consists of a 432 m circumference storage ring with an operating energy of 3.5GeV and a minimum emittace of 2.95 nm-rad, a full energy bosster, a 100MeV electron Linac and dozens of beamlines and experimental stations. The design of the SSRF accelerator complex evolves timely along the technological progress such as top-up injection, mini-gap undulator, superconducting RF system and etc. This paper reports the design progress and status of the SSRF project.  
 
THPKF045 Accelerator Physics Issues at NSRRC insertion, insertion-device, coupling, synchrotron 2377
 
  • C.-C. Kuo, H.-P. Chang, P.J. Chou, K.-T. Hsu, G.-H. Luo, H.-J. Tsai, M.-H. Wang
    NSRRC, Hsinchu
  Over the past decade, NSRRC has served the synchrotron light users with its 1.5 GeV third-generation storage ring. To provide stable hard x-ray for the x-ray community, two strong-field superconduting wigglers have been installed and three more will be put in such a low energy ring. A superconduting rf cavity is to replace the conventional ones and the beam current will be double too. Top-up injection study is underway. This paper presents the accelerator physics issues at NSRRC such as single particle dynamics and collective effects.  
 
THPKF046 Feasibility Study of Constant Current Operation at TLS Storage Ring storage-ring, photon, insertion, insertion-device 2380
 
  • G.-H. Luo, H.-P. Chang, J. Chen, C.-C. Kuo, K.-B. Liu, R.J. Sheu, H.-J. Tsai, M.-H. Wang
    NSRRC, Hsinchu
  Several top-up experiments were carried out at various upgrade path of Taiwan Light Source. However, there were too many obstacles laid ahead of various stages to prevent the realization of top-up injection routinely. The small gap undulators, the requirement of small emittance operation and high current operation by SC cavity have promoted the top-up injection project to hightest priority. During last one and half years, a series of beam parameters measurement, subsystem checkout, installing various sensors, control program modification and hardware upgrade made the top-up injection more likely in routine operation. Discussions on the results of some measurements of booster and storage ring, the requirement of hardware upgrade and the future executable plan will be presented in this paper.  
 
THPKF059 Adaption of an RF-gun from Thermionic to Photo Cathode laser, cathode, gun, electron 2397
 
  • S. Werin, M. Berglund, M. Brandin, T. Hansen
    MAX-lab, Lund
  The current electron source for the injector at MAX-lab is a thermionic RF-gun. This gun produces a several ns long pulse with a significant beamloading. To allow for ?few bucket? operation and emittance reduction the gun will be adapted for operation with a ns laser system. The system to be installed during the spring 2004 is a 3 or 4th harmonic injection seeded Nd:YAG laser. The thermionic BaO cathode already in use will be used at a temperature just below thermal emission where a quantum efficiency of around 1* 10-4 is expected.  
 
THPKF064 Status of Kharkov X-ray Generator based on Compton Scattering NESTOR storage-ring, quadrupole, laser, electron 2412
 
  • A.Y. Zelinsky, V.P. Androsov, E.V. Bulyak, I.V. Drebot, P. Gladkikh, V.A. Grevtsev, V.A. Ivashchenko, I.M. Karnaukhov, V. Lapshin, V. Markov, N.I. Mocheshnikov, A. Mytsykov, F.A. Peev, A.V. Rezaev, A.A. Shcherbakov, V.L. Skirda, V.A. Skomorokhov, Y.N. Telegin, V.I. Trotsenko
    NSC/KIPT, Kharkov
  • A. Agafonov, A.N. Lebedev
    LPI, Moscow
  • J.I.M. Botman
    TUE, Eindhoven
  • T.R. Tatchyn
    SLAC/SSRL, Menlo Park, California
  Nowadays the sources of the X-rays based on a storage ring with low beam energy and Compton scattering of intense laser beam are under development in several laboratories. In the paper the state-of-art in development and construction of cooperative project of a Kharkov advanced X-ray source NESTOR based on electron storage ring with beam energy 43 - 225 MeV and Nd:YAG laser is described. The layout of the facility is presented and main results and constructing timetable are described. The designed lattice includes 4 dipole magnets with combined focusing functions, 20 quadrupole magnets and 19 sextupoles with octupole component of magnetic field. At the present time a set of quadrupole magnet is under manufacturing and bending magnet reconstruction is going on. The main parameters of developed vacuum system providing residual gas pressure in the storage ring vacuum chamber up to 10-9 torr are presented along with testing measurement at NSC KIPT vacuum bench. The facility is going to be in operation in the middle of 2006 and generated X-rays flux is expexted to be of about 1013 phot/s.  
 
THPKF067 Progress of the DIAMOND Storage Ring and Injector Design. storage-ring, booster, septum, coupling 2418
 
  • S.L. Smith, D.J. Holder, J.K. Jones, J.A. Varley, N.G. Wyles
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  • R. Bartolini, I.P.S. Martin, B. Singh
    Diamond, Oxfordshire
  DIAMOND is a state of the art 3 GeV synchrotron light source that will be available to users in 2007. Considerable further progress has been made on the accelerator physics design of the storage ring, booster and other associated injector systems. Detailed analysis of injection processes, lifetime, coupling, instabilities, feedback systems and dynamic aperture have been undertaken driven by the procurement activity and the desire to fully understand all aspects of the accelerator's performance.  
 
THPKF069 Improvements to, and Current Status of, the CAMD Light Source wiggler, power-supply, lattice, diagnostics 2424
 
  • V.P. Suller, M.G. Fedurin, P. Jines, D.J. Launey, T.A. Miller, Y. Wang
    LSU/CAMD, Baton Rouge, Louisiana
  Throughout 2003 a sustained program of modifications and improvements has been applied to the CAMD light source. These affected the 7 Tesla wiggler, the RF system, the magnet power supplies, the control system, the diagnostics and the injector linac. These modifications and their impact on the storage ring performance are described, together with an analysis of where future improvements should be directed. The present performance and limitations of CAMD are described.  
 
THPKF072 Progress with the Diamond Light Source vacuum, storage-ring, booster, diagnostics 2433
 
  • R.P. Walker
    Diamond, Oxfordshire
  Construction of Diamond, the UK?s new 3 GeV, 3rd generation synchrotron light source, is well underway and progressing in-line with the original target of starting storage ring commissioning in January 2006 and being operational for users in January 2007. Having completed the foundations, the main building works are now proceeding at their maximum rate. Most of the major machine components are also under construction, aiming towards the key target date of starting machine installation in September 2004. As well as reporting on the overall status, detailed design developments and component choices will be summarised. The results of tests of various prototype components, including magnets, vacuum vessels and girders, will also be presented.  
 
THPKF076 Plan to Upgrade the Advanced Light Source to Top-off Injection Operation septum, radiation, brightness, emittance 2442
 
  • D. Robin, B. J. Bailey, K.M. Baptiste, W. Barry, E. Byrne, J.-Y. Jung, S. Kwiatkowski, R.S. Mueller, H. Nishimura, S. Prestemon, S.L. Rossi, F. Sannibale, D. Schlueter, D. Shuman, C. Steier, G.D. Stover, T. Warwick
    LBNL, Berkeley, California
  • R.J. Donahue
    LBNL/ALS, Berkeley, California
  The brightness and thermal stability of the Advanced Light Source (ALS) is lifetime limited. Brightness improvements such as narrower gap insertion devices, smaller emittance coupling, and higher currents all result in short lifetimes. In addition current changes over a fill impact the thermal stability of both the storage ring and beamlines. In order to mitigate these limitations there is a plan to upgrade the injector of the ALS to full energy injection and to operate in a quasi-continuous filling (Top-Off) injection operation. With Top-Off, the ALS will increase its time-averaged current by two, reduce the vertical emmittance, and operate with smaller gap insertion devices. In this paper we describe our upgrade plan.  
 
THPKF082 The Completion of SPEAR 3 vacuum, shielding, power-supply, radiation 2451
 
  • R.O. Hettel, R. Akre, S. Allison, P. Bellomo, R.M. Boyce, L. Cadapan, R. Cassel, B. Choi, W.J. Corbett, D. Dell'Orco, T. Elioff, I. Evans, R. Fuller, S. Hill, D. Keeley, N. Kurita, J. Langton, G. Leyh, C. Limborg-Deprey, D. Macnair, D.J. Martin, P.A. McIntosh, E. Medvedko, C.-K. Ng, I. Nzeadibe, J. Olsen, M. Ortega, G.C. Pappas, S. Park, T. Rabedeau, H. Rarback, A. Ringwall, P. Rodriguez, J.A. Safranek, H.D. Schwarz, B. Scott, J.J. Sebek, S. Smith, T. Straumann, J. Tanabe, A. Terebilo, T.A. Trautwein, C. Wermelskirchen, M. Widmeyer, R. Yotam, K. Zuo
    SLAC/SSRL, Menlo Park, California
  On December 15, 2003, 8 1/2 months after the last electrons circulated in the old SPEAR2 storage ring and 5 days after the beginning of commissioning, the first electrons were accumulated in the completely new SPEAR3 ring. The rapid installation and commissioning is a testimony to the SPEAR3 project staff and collaborators who have built an excellent machine and equipped it with powerful and accessible machine modeling and control programs. The final year of component fabrication, system implementation and testing, the 7-month installation period leading up to the beginning of commissioning, and lessons learned are described.  
 
THPLT009 Comparative Transverse Distribution Measurements between the New SPS Rest Gas Ionisation Monitor and the Wire Scanner Monitors. emittance, acceleration, proton, target 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.  
 
THPLT015 Accuracy of Profile Monitors and LHC Emittance Measurements emittance, booster, proton, 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.  
 
THPLT020 The DSP-based Betatron Tune Feedback of the Ramped 1.5 GeV Electron Storage Ring BoDo feedback, betatron, optics, power-supply 2511
 
  • B. Keil
    PSI, Villigen
  • K. Wille
    DELTA, Dortmund
  The ramped storage ring BoDo is the full energy injector of the 1.5 GeV synchrotron light source DELTA. All ramped booster magnet power supplies, RF power and beam diagnostics of BoDo are handled by a distributed VME-based DSP (digital signal processor) multiprocessing system developed at DELTA. The VME DSP boards of this system are interconnected by DeltaNet, a novel reflective memory ring network. DeltaNet transmits the measurement data from each DSP board to all other boards in real-time via fibre optic links. The generic hardware and software architecture of the system allows the implementation of different kinds of global real-time feedbacks with correction rates in the range from some 100 Hz to some 10 kHz. This paper presents architecture and performance of a real-time betatron tune feedback that was implemented with the DSP system. The betatron tune is measured and corrected in both planes at a rate of typically 700 Hz for arbitrary beam optics and energy ramps of BoDo. In combination with the global Bodo orbit feedback, the tune feedback increases the performance of Bodo both as an injector and as a testbed for machine studies and newly developed accelerator components.  
 
THPLT056 Horizontal Instability and Feedback Performance in DAFNE e+ Ring feedback, damping, pick-up, positron 2613
 
  • A. Drago
    INFN/LNF, Frascati (Roma)
  In DAFNE, after the 2003 shutdown for the installation of FINUDA, a strong horizontal multibunch instability was found to limit the positron beam current at the level of ~450 mA. We have performed transverse grow-damp measurements in order to estimate the instability growth rates as well as the feedback damping rates for each bunch at different beam currents and to evaluate the tune shift along the bunch train. In particular, a strong dependence of oscillation amplitudes on the relative position of the bunch in the train has been observed. In this paper we describe the setup for multibunch oscillation amplitude recording, discuss the transverse feedback performance and summarize some observations on the transverse instability. The feedback rises the threshold by about a factor of two, depending on the machine configuration.  
 
THPLT061 Development of a Multibunch Photo-cathode RF Gun System gun, laser, cathode, electron 2628
 
  • J. Urakawa, M. Akemoto, S. Araki, H. Hayano, M. Kuriki, T. Muto, N. Terunuma, Y. Yamazaki
    KEK, Ibaraki
  • M.K. Fukuda, K. Hirano, M. Nomura, M. Takano
    NIRS, Chiba-shi
  A multibunch photo-cathode RF gun system has been developed as a electron source for the production of quasi-monoenergetic X-rays based on inverse Compton scattering. This system consists of a photocathode rf gun, a cathode system, a laser system, beam diagnostic sections, and beam dump line. The gun produces 100 bunches with a 2.8ns bunch spacing and 5nC bunch charge. We will report on the RF gun system with 4 bending dipoles of a chicane which makes the laser injection to the cathode with perpendicular angle possible.  
 
THPLT065 Study of Multiturn Injection at HIMAC Synchrotron simulation, optics, synchrotron, emittance 2640
 
  • T.H. Uesugi, T. Furukawa, T. Naruse, K. Noda
    NIRS, Chiba-shi
  • T. Fujimoto, S. Shibuya
    AEC, Chiba
  In the multiturn injection method at the HIMAC synchrotron, a collapsing speed of the bump orbit was decreased from 200 to 350 microseconds in order to obtain higher intensity beam. The injection line was readjusted to satisfy the optimum condition of multiturn injection method. Furthermore, COD correction and bump-orbit optimization were carried out. On the other hand, in order to prevent the resonance by tune shift and to keep the beam intensity constant, tune survey was carried out. While vertical tune is adjusted, we propose that the method to reduce beam loss after injection by expanding vertical beam size by means of the RF-knockout. This paper describes the improvement of injection at HIMAC synchrotron.  
 
THPLT066 Commissioning of 150MeV FFAG Synchronisation septum, extraction, acceleration, kicker 2643
 
  • Y. Yonemura, M. Matoba
    Kyushu University, Fukuoka
  • M. Aiba, M. Sugaya
    University of Tokyo, Tokyo
  • S. Machida, Y. Mori, A. Muto, J. Nakano, C. Ohmori, I. Sakai, Y. Sato, A. Takagi, T. Yokoi, M. Yoshii, M. Yoshimoto, Y. Yuasa
    KEK, Ibaraki
  • T. Uesugi
    NIRS, Chiba-shi
  • A. Yamazaki
    LNS, Sendai
  A 150MeV proton FFAG (Fixed Field Alternating Gradient) synchrotron has been constructed to be a prototype for various applications such as proton beam therapy. At the moment, all the components are assembled, and multi-turn injection and beam storage were successfully performed. We are in the phase of beam acceleration up to final energy and expect the beam extraction in a few months. In this paper, beam commissioning results such as multi-turn injection, orbit correction, tune survey and optimization of RF gymnastics will be presented.  
 
THPLT068 Transverse Bunch-by-bunch Feedback System for the SPring-8 Storage Ring feedback, damping, storage-ring, emittance 2649
 
  • T. Nakamura, S. Daté, T. Ohshima
    JASRI/SPring-8, Hyogo
  • K. Kobayashi
    SES, Hyogo-pref.
  A transverse bunch-by-bunch feedback system is developed for the SPring-8 storage ring. An analog de-multiplexer is developed to slice out every six-bunch signal for high-resolution 12-bit ADCs of clock frequency 85MHz, one-sixth of 508MHz RF frequency. Six commercial ADC-FPGA-DAC boards are used for processing the signal from the de-multiplexer. A custom FPGA board is used to multiplex the output signals from those boards. The feedback system is installed in the ring and working with the damping time of 0.5~2.5ms in 30kHz-254MHz and can suppress multi-bunch instabilities driven by impedances of resistive-wall of in-vacuum insertion devices and cavity HOMs at low chromaticity operation.  
 
THPLT071 Upgraded Symplectic 3D Beam Tracking of the J-PARC 3 GeV RCS quadrupole, space-charge, emittance, simulation 2658
 
  • M.J. Shirakata, H. Fujimori, Y. Irie
    KEK, Ibaraki
  The J-PARC 3 GeV ring is a rapid cycling synchrotron which consists of the large bore size magnets. The beam tracking with the 3D distributed magnetic fields is kept developing in order to investigate the beam injection process. In the case of the high intensity hadron accelerator, an accurate beam simulation is important for the designing because a very small amount of beam loss can be critical from the maintenance point of view. In order to improve the tracking accuracy and to save the calculation time, the symplectic integration with the fractal decomposition method has been introduced. The updated simulation results of the beam injection on the J-PARC 3 GeV RCS and the improved performance of ‘GenericSolver' are presented in this paper. The quadrupole fields are also treated as the 3D distributed magnetic fields because they interfered with the bump magnet fields. The remarkable features on the large bore magnet system in the ring accelerator are also discussed.  
 
THPLT073 Numerical Methods for the Orbit Control at the KEK 12 GeV PS beam-losses, synchrotron, closed-orbit, vacuum 2664
 
  • Y. Hitaka, H. Sato, M.J. Shirakata
    KEK, Ibaraki
  • M.K. Kono, Y.M. Yokomichi
    Miyazaki University, Miyazaki
  At the KEK 12GeV-PS main ring, when the least square method is applied to correct whole beam orbit all at once, it remains unacceptable beam loss and it is necessary to adjust the local positions of the beam orbit by hands with the beam loss monitors until the beam loss is suppressed under an acceptable level. However, the orbit does not realize the minimum-loss condition. In this paper, a new method is proposed. It focuses a fact that the beam loss distribution depends on the shape of the beam orbit and formulates this relationship to a functional approximation by using a nural network algorithm. Then, solving an optimization problem for generated network system, data of the beam shape which is more suitable for the beam loss of the accelerator can be obtained. The description of the system construction and experimental results are presented.  
 
THPLT074 The Beam Loss Monitor System of the J-parc LINAC, 3 GEV RCS and 50 GEV MR beam-losses, linac, extraction, radiation 2667
 
  • S. Lee, T. Toyama
    KEK, Ibaraki
  • J. Kishiro
    JAERI/LINAC, Ibaraki-ken
  • M. Tanaka
    JAERI, Ibaraki-ken
  The high intensity beam accelerator complex itself requires the significant progress of design study and hardware R&D. Operational beam intensity should be limited by the beam loss and activation level of the equipment. Once the beam loss exceeds a criterion at outer environment, beam intensity has to be decreased to prevent the further activation. In order to investigate loss mechanism and suppress the beam loss, a beam loss monitor system have been developed for the J-PARC linac, 3 GeV RCS and 50GeV MR. The system will be essential component for beam commissioning, tuning and machine protection in high intensity beam accelerators. The loss monitor system is composed of scintillator, argon-methane/3He gas filled proportional counter and air filled coaxial cable ionization chamber, which detect g-ray, neutron and charged particles induced by lost particle. It is necessary to measure wide dynamic range of loss intensity for various beam energies. To prevent the activation and heat load by intense beam loss, fast time response of loss signals is required. In this paper, construction and application of loss monitor system are described in detail. Preliminary result of demonstration in the KEK-PS and calibration with cobalt 60 g-ray radiation source are also discussed.  
 
THPLT099 The Analysis of the Electron Beam Scanning Method for the Beam Profile Monitoring. electron, ion, scattering, space-charge 2721
 
  • D.A. Liakin
    ITEP, Moscow
  The method of the beam profile monitoring with scanning electron beam is analyzed. Simulation model of the ion/electron beam interaction is presented and some simulation results are shown. In the report the estimation of overall performance characteristics of this method such as sensitivity, spatial resolution, frequency bandwidth etc. are given.  
 
THPLT100 Development of a Permanent Magnet Residual Gas Profile Monitor With Fast Readout electron, ion, synchrotron, photon 2724
 
  • D.A. Liakin, S.V. Barabin, V. Skachkov
    ITEP, Moscow
  • P. Forck, T. Giacomini
    GSI, Darmstadt
  • A. Vetrov
    MSU, Moscow
  The beam profile measurement at modern ion synchrotrons and storage rings require high timing performances on a turn-by-turn basis. From the other hand, high spatial resolutions are very desirable for cold beams. We are developing a residual gas monitor to cover the wide range of beam currents and transversal distributions of particles. It supplies the needed high-resolution and high-speed tools for beam profiling. The new residual gas monitor, will operate on secondary electrons whose trajectories are localized within 0.1 mm filaments. The required magnetic field of 100 mT will be excited by a permanent magnet. In the fast turn-by-turn mode the beam profile will be read out with a resolution of 1 mm by a 100-channel photodiode-amplifier-digitizer. The high resolution mode of 0.1 mm is provided by a CCD camera with upstream MCP-phosphor screen assembly. In this paper the first results of the photodiode-digitizer device testing, the compact mechanical design features and simulation results of the permanent magnet device are presented.  
 
THPLT112 Methods and Instrumentation for Measurement of Low Ion Beam Currents at Cryring ion, pick-up, background, monitoring 2748
 
  • A. Paal, A. Källberg, A. Simonsson
    MSL, Stockholm
  • J. Dietrich, I. Mohos
    FZJ/IKP, Jülich
  In many CRYRING experiments an accurate measurement of the circulating ion beam current is essential for determination of e.g. absolute cross sections. However, the current produced from the ion source can be very low. Furthermore, when surface barrier detectors are used, for example in the merged electron-ion beam experiments, the current has to be kept low to avoid saturation. With new electronics, using an Integrating Current Transformer with 5 V/A sensitivity, the current resolution of the Bergoz Beam Charge Monitor (BCM) has been increased to below 1 nA for bunched beams. The sum signal of the capacitive pick-up located at the farthest point from the RF-system is integrated by a second gated integrator. The RMS resolution is about 100 pA. To measure the intensity of coasting beams neutral particle detectors and a residual-gas beam profile monitor are used, calibrated with the BCM output during 20-100 ms after acceleration. The micro-channel plate detectors can handle a few Mcps count rate with a maximum 1 cps dark count rate. Presently a 50 Mcps secondary electron multiplier is being tested as a neutral particle monitor, having a maximum dark count rate of 0.05 cps  
 
THPLT130 Synchronization of the Fermilab Booster and Main Injector for Multiple Batch Injection booster, feedback, extraction, proton 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.  
 
THPLT146 Beam Diagnostics of the Small Isochronous Ring diagnostics, emittance, extraction, space-charge 2798
 
  • J.A. Rodriguez, F. Marti
    NSCL, East Lansing, Michigan
  • E. Pozdeyev
    Jefferson Lab, Newport News, Virginia
  The purpose of this paper is to describe the beam diagnostic systems in the Small Isochronous Ring (SIR) developed and built at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU). SIR is a small-scale experiment that simulates the dynamics of intense beams in large accelerators. A 20 to 30 keV hydrogen or deuterium ion bunch is injected in the ring, extracted after a variable number of turns and its longitudinal profile is studied. Some of the diagnostic tools available in SIR include an emittance measurement system in the injection line, scanning wires in different sections of the ring, phosphor screens at the injection and extraction points and a fast Faraday cup in the extraction line. The design of these systems and the kind of beam information they provide are discussed in detail.  
 
THPLT166 Development of Injection and Optics Control Applications for the SNS Accumulator Ring optics, linac, quadrupole, sextupole 2849
 
  • S.M. Cousineau, C. Chu, J. Galambos, S. Henderson, T. Pelaia, M. Plum
    ORNL/SNS, Oak Ridge, Tennessee
  • A.L. Leahman
    WSSU, Winston-Salem, North Carolina
  A large suite of physics software applications is being developed to facilitate beam measurement and control in the SNS accumulator ring. Two such applications are an injection control and measurement application, and a ring optics control application. The injection application will handle measurement and control of the linac beam position and angle at the stripper foil, and will be used to measure the twiss parameters of the linac beam at the foil. The optics control application will provide knobs for machine working point, chromaticity, arc phase advance, and harmonic correction. Both applications are written within the standard in-house XAL framework. Presented here are first versions of the applications, along with plans for future development and testing.  
 
THPLT186 Bunch Pattern Control in Top-up Mode at the SLS feedback, storage-ring, controls, diagnostics 2885
 
  • B. Kalantari, T. Korhonen, V. Schlott
    PSI, Villigen
  One of the crucial issues in the advanced third generation light sources is the bunch pattern control in the storage ring, where various filling patterns are of interests for different experiments. The most important step is to keep a uniform charge distribution over all (electron) bunches during the top-up operation. Such a bunch pattern control has been implemented at the Swiss Light Source (SLS). It provides a filling pattern with bunch-to-bunch fluctuation of a few percent. Since a dependency of the medium term orbit stability on the actual filling pattern was observed in the past, the stability could significantly be improved. Three major ingredients have made the implementation possible: precise timing system, flexible control system and sophisticated diagnostics. The method is being used in the user operation recently and proved to be reliable. This paper describes the hardware and software involved in the mentioned technique.  
 
FRXCH01 Development of High Power Targets target, radiation, proton, 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
 
FRYACH01 HICAT - The German Hospital-Based Light Ion Cancer Therapy Project ion, synchrotron, extraction, beam-transport 290
 
  • H. Eickhoff, T. Haberer, B. Schlitt, U. Weinrich
    GSI, Darmstadt
  At the University Clinics at Heidelberg /Germany the realization of a cancer Therapy facility using light and medium ions (from protons up to oxygen) has started. This facility will be capable to treat about 1000 patients per year by means of the 'intensity controlled rasterscan technique', that has been already successfully applied to about 200 patients since 1998 at the GSI therapy pilot project. The presentation will give an overview of the facility layout and especially the accelerator- and beam transport systems, capable to provide 3 treatment places with light ions between 50 and 430 MeV/u. Two treatment places are located after horizontal beam lines and one after an isocentric gantry. A further horizontal beam line for research and development activities is foreseen. Besides the technical description and the status and schedule for the project realization organizational aspects of this project will be discussed with the project leadership at the University Clinics, the strong technical assistance of GSI and the role of industrial partners.  
Video of talk
Transparencies