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MOXPA01 | The Global Design Initiative for an International Linear Collider | collider, positron, linear-collider, electron | 1 | ||||
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Two years after the selection of the SC technology and a few months before the release of the ILC Conceptual Design Report, the presentation will review the main issues towards an ILC project and the world-wide collaboration presently set-up to address them. It will especially emphasize the challenges both technical (performances, reliability, machine protection, cost minimisation, industrialisation) and organisational, in a world-wide collaboration for the first time from the very beginning of the project. It will then present the status of the performances already demonstrated, the R&D presently envisaged to improve them or reduce the cost, the test facilities set-up to address them and the effort towards technology transfer to industry and industrialisation. Finally, it will present the plans and schedule for the future as well as the site specific parameters and cost issues.
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Transparencies
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MOZAPA02 | Commissioning Highlights of the Spallation Neutron Source | SNS, linac, target, extraction | 29 | ||||
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The Spallation Neutron Source (SNS) is a second generation pulsed neutron source at Oak Ridge National Laboratory. The SNS is funded by the U.S. Department of Energy's Office of Basic Energy Sciences and is dedicated to the study of the structure and dynamics of materials by neutron scattering. A collaboration composed of six national laboratories (ANL, BNL, TJNAF, LANL, LBNL, ORNL) is responsible for the design and construction of the various subsystems. With the official start in October 1998, the operation of the full facility has begun in late spring 2006 delivering a 1.0 GeV proton beam with a pulse length of approximately 700 nanoseconds on a liquid mercury target. Within the next two years a beam power of more than one MW should be achieved. The multi-lab collaboration provided a large variety of expertise in order to enhance the beam power delivered by the accelerator by almost an order of magnitude compared to existing neutron facilities. The SNS linac consists of a room temperature and superconducting (sc) structures and is the first pulsed high power sc linac in the world. The compressor ring and the target are the final subsystems that were commissioned during early 06.
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Transparencies
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MOPCH012 | FEL Disturbance by Ambient Magnetic Field Changes | PETRA, DESY, linac, electron | 74 | ||||
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The VUV-FEL at DESY in Hamburg (Germany) is mostly located inside the circular accelerator PETRA which serves as an injector for the electron proton collider HERA. SASE was regularly lost in the VUV-FEL when protons were ramped to the injection energy in PETRA. This effect was mediated by magnetic field changes in the order of 1 microtesla, caused by time-dependent uncompensated magnet currents of more than 800 A which made PETRA act like a large current loop. The resulting beam displacements of several hundred micrometers in the undulators proved to be enough to make SASE fail. This serious disturbance of user runs was eliminated by introducing an improved compensation scheme which further limits residual currents in PETRA during proton injection. The consequences of this observation for the design of the XFEL are briefly discussed.
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MOPCH084 | From COSY to HESR | target, COSY, electron, antiproton | 226 | ||||
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The High Energy Storage Ring (HESR) at the proposed Facility for Antiproton and Ion Research (FAIR) puts strong demands on quality and intensity of the stored antiproton beam in the presence of thick internal targets. The existing synchrotron and storage ring COSY in Juelich can be seen as a smaller model of the HESR. In this paper we will discuss possible benchmarking experiments at COSY, involving effects like beam cooling, target heating, intra-beam scattering, etc. The aim of these experiments is to support the design work for the HESR and ensure that the specified beam conditions can be achieved.
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MOPCH087 | Quasi-adiabatic Transition Crossing in the Hybrid Synchrotron | synchrotron, acceleration, induction, beam-losses | 234 | ||||
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Non-adiabatic features around the transition energy are well-known to be one of most important beam physics issues in most of circular hadron accelerators. A novel technique to avoid them by the adiabatic motion, a quasi-adiabatic focusing-free transition crossing (QAFFTC), was proposed. In a longitudinally separated function-type accelerator*, in which particles are confined by an rf voltage or burrier voltages and accelerated by a step voltage, the confinement voltage can be arbitrarily manipulated as long as the particles do not diffuse, while a strict acceleration voltage is necessary for the orbit of a charged particle to be balanced in the radial direction. The introduction of QAFFTC is most suitable for the longitudinally separated function-type accelerator. This new method was examined in this type of accelerator**, both theoretically and experimentally. This was a first and significant application of the hybrid synchrotron. The results will be presented.
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*K. Takayama and J. Kishiro, Nucl. Inst. Meth. A 451, 304 (2000).**K. Takayama et al. Phys. Rev. Lett. 94, 144801 (2005). |
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MOPCH088 | Ion Cooler Storage Ring, S-LSR | laser, ion, electron, beam-cooling | 237 | ||||
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Ion cooler and storage ring, S-LSR has been constructed. Its beam commissioning has been successfully performed since October, 2005 and electron beam cooling for 7 MeV proton beam has been performed with both flat and hollow spatial distributions. Effect of relative velocity sweep between electron and ion beams on the cooling time* has been confirmed. Based on the success to create the peaks in the energy spectrum of laser-produced ions, injection of laser-produced ions into S-LSR after rotation in the longitudinal phase space by an RF cavity synchronized to the pulse laser is under planning in order to apply electron cooling for such real laser produced hot ions. Three dimensional laser cooling satisfying the condition of 'tapered cooling' is also under investigation. 24Mg+ ions are to be laser-cooled only in the 'Wien Filter' in order to be cooled down to the appropriate energy according to their horizontal positions**. In parallel with the computer simulation, construction of the laser cooling system with use of ring dye laser accompanied with the second harmonics generator is now underway.
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*H. Fadil et al. Nucl. Instr. & Meth. in Phys. Res. A517, 1-8 (2004).**A. Noda and M. Grieser, Beam Science and Technology, 9, 12-15 (2005). |
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MOPCH092 | CRYRING Machine Studies for FLAIR | CRYRING, ion, antiproton, space-charge | 249 | ||||
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At the FLAIR facility (Facility for Low-energy Antiproton and Ion Research) at FAIR, antiprotons and heavy ions will be decelerated to very low energies and ultimately to rest. One step in this deceleration is made in the magnetic storage ring LSR (Low-Energy Storage Ring). CRYRING at the Manne Siegbahn Laboratory in Stockholm will be closed down within the next few years, and since CRYRING has an energy range quite similar to the proposed LSR, is equipped with beam cooling, and has several other features required for a deceleration ring, plans are being made for the transfer of CRYRING to FAIR and for its use as the LSR ring. This paper describes some of the characteristics of CRYRING relevant for its new role, modifications that need to be made, and test that have been performed at CRYRING with, e.g., deceleration of protons from 30 MeV to 300 keV kinetic energy, which is the proposed energy range for antiprotons at LSR.
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MOPCH094 | Low-intensity Beams for LHC Commissioning from the CERN PS-booster | LHC, emittance, injection, CERN | 255 | ||||
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A variety of low-intensity beams will be required for LHC commissioning. In contrast to the nominal LHC physics beam, these single-bunch beams are produced without longitudinal bunch splitting in the injector chain. Consequently, not only the transverse but also the longitudinal beam characteristics have already to be established in the CERN PS-Booster. The required intensities extend down to four orders of magnitude below the typical PS-Booster working range and the transverse emittances must be adjustable to vary the beam brightness over a large range. The different beam variants are briefly summarized and the specific techniques developed for their production, like low-voltage rf capture, and transverse and longitudinal shaving, are described. In particular, the choice of harmonic number and its consequences for operation and beam reproducibility are discussed. Finally, the performance achieved for the different beams is summarized.
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MOPCH101 | On the Feasibility of a Spin Decoherence Measurement | polarization, RHIC, synchrotron, AGS | 276 | ||||
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In this paper, we study the feasibility of making a turn-by-turn spin measurement to extract the spin tune of a synchrotron from a polarized beam injected perpendicular to the stable spin direction. For the ideal case of a zero-emittance beam with no spin-tune spread, there would be no spin decoherence and a measurement of the spin tune could easily be made by collecting turn-indexed polarization data of several million turns. However, in a real beam there is a momentum spread which provides a tune spread. With a coasting beam the tune spread will cause decoherence of the spins resulting in a fast depolarization of the beam in a thousand turns. With synchrotron oscillations the decoherence time can be greatly increased, so that a measurement becomes feasible with summation of the turn-by-turn data from a reasonable number of bunches (100 or fewer). Both the cases of a single Siberian snake and a pair of Siberian snakes are considered.
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MOPCH105 | A New RF Tuning Method for the End Regions of the IPHI 4-vane RFQ | rfq, simulation, quadrupole, dipole | 285 | ||||
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The 3-MeV High Intensity Proton Injector (IPHI) RFQ is constituted by the assembly of three 2-m-long segments. The tuning of the end regions of such an accelerator with respect to the quadrupole mode is generally made by machining the thickness of the end plates. The dipole modes are moved away from the accelerator mode frequency by adding dipole rods and adjusting their length. In the case of the last IPHI RFQ segment, the tuning range given by possible plate thickness was not sufficient to adjust the frequency at 352 Mhz without modifying the notch depth, leading to serious engineering problems for the cooling, new thermo-mechanical simulations and drawings. To avoid these difficulties, a new way has been investigated by replacing the end plate thickness adjustment by a "quadrupole rod" length adjustment. These rods are situated between the beam axis and the dipole rods, and the tuning range is largely increased. The paper will describe this method applied to the IPHI RFQ and some experimental results obtained on the cold model.
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MOPCH111 | A Fast Beam Chopper for the RAL Front End Test Stand | emittance, linac, CERN, quadrupole | 300 | ||||
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The FETS project at RAL will test a fast beam chopper, designed to address the requirements of high power proton drivers for next generation pulsed spallation sources and neutrino factories. A description is given of the novel RAL 'Fast - Slow' chopping scheme, and of candidate optical designs for the 3.0 MeV, 60 mA, H- Medium Energy Beam Transport (MEBT) line.
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MOPCH113 | Re-bunching RF Cavities and Hybrid Quadrupoles for the RAL Front-end Test Stand (FETS) | quadrupole, impedance, linac, CCL | 306 | ||||
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The proposed FETS project at RAL will test a fast beam chopper in a 3.0 MeV H- Medium Energy Beam Transport (MEBT) line. Space restrictions in the MEBT line place constraints on component length and drive the requirement to identify compact component configurations. A description is given of candidate re-bunching RF cavities and hybrid quadrupole designs. The cavity options considered are the space efficient Drift Tube Linac type cavity (DTL) with integrated quadrupoles, and the high shunt impedance Coupled Cavity Linac type cavity (CCL) with external quadrupoles. The advantages and disadvantages of both structures are discussed and a comprehensive comparison between the two is made enabling the best cavity geometry choice. The compact hybrid quadrupole configurations considered are the 'tandem' combination of permanent magnet (PMQ) and electro-magnetic (EMQ) types, and the concentric combination of PMQ and laminar conductor (Lambertson) EMQ types.
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MOPCH114 | Progress on Dual Harmonic Acceleration on the ISIS Synchrotron | acceleration, synchrotron, power-supply, controls | 309 | ||||
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The ISIS facility at the Rutherford Appleton Laboratory in the UK is currently the most intense pulsed, spallation, neutron source. The accelerator consists of a 70 MeV H- Linac and an 800 MeV, 50 Hz, rapid cycling, proton Synchrotron. The synchrotron beam intensity is 2.5·1013 protons per pulse, corresponding to a mean current of 200 μA. The synchrotron beam is accelerated using six, ferrite loaded, RF cavities with harmonic number 2. Four additional, harmonic number 4, cavities have been installed to increase the beam bunching factor with the potential of raising the operating current to 300 μA. As ISIS has a busy user schedule the time available for dual harmonic work has been limited. However, much progress has been made in the last year and encouraging results have been obtained. This paper reports on the hardware commissioning and beam tests with dual harmonic acceleration.
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MOPCH119 | Present Status of the Induction Synchrotron Experiment in the KEK PS | induction, acceleration, synchrotron, KEK | 324 | ||||
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A concept of the induction synchrotron, which was proposed by Takayama and Kishiro in 2000, has been demonstrated by using the KEK PS since 2004. A proton bunch trapped in the RF bucket was accelerated with the induction acceleration devices from 500 MeV to 8 GeV*, which was energized with the newly developed switching power supply. This form of the KEK PS is something like a hybrid synchrotron. In addition, the injected proton bunch was confined by the step barrier-voltages at the injection energy of 500MeV**, which were generated with the same induction acceleration device. Then a concept of the induction synchrotron that a proton bunch was captured by the barrier bucket and accelerated with the induction voltage is to be fully demonstrated.
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*K. Takayama et al. "Observation of the Acceleration of a Single Bunch by Using the Induction Device in the KEK Proton Synchrotron", Phys. Rev. Lett., 94, 144801 (2005).**K. Torikai et al. "Acceleration and Confinement of a Proton Bunch with the Induction Acceleration System in the KEK Proton Synchrotron", submitted to Phys. Rev. ST-AB (2005), KEK-Preprint 2005-80 A, December 2005. |
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MOPCH124 | Energy Deposition in Adjacent LHC Superconducting Magnets from Beam Loss at LHC Transfer Line Collimators | LHC, simulation, beam-losses, collimation | 336 | ||||
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Injection intensities for the LHC are over an order of magnitude above the damage threshold. The collimation system in the two transfer lines is designed to dilute the beam sufficiently to avoid damage in case of accidental beam loss or mis-steered beam. To maximise the protection for the LHC most of the collimators are located in the last 300 m upstream of the injection point where the transfer lines approach the LHC machine. To study the issue of possible quenches following beam loss at the collimators the entire collimation section in one of the lines, TI 8, together with the adjacent part of the LHC has been modeled in FLUKA. The simulated energy deposition in the LHC for worst-case accidental losses as well as for losses expected during a normal filling is presented. The operational implications are discussed.
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MOPCH126 | Accelerator Research on the Rapid Cycling Synchrotron at IPNS | acceleration, synchrotron, extraction, injection | 339 | ||||
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The Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory is a national user facility for neutron scattering. Neutrons are produced by 70 ns pulses of protons (~3x 1012 protons per pulse) impacting a depleted-uranium target at a pulse repetition rate of 30 Hz. Three accelerators in series (a 750 keV Cockcroft-Walton, 50 MeV Alvarez linac accelerating H- ions, and a 450 MeV rapid-cycling proton synchrotron) provide the beam that is directed to the target. New diagnostics and a third rf cavity that can be operated at either the fundamental or second harmonic of the ring frequency have recently been installed and an experimental program established to try to gain understanding of an instability that limits the charge-per-bunch in the RCS. This program will be described, and preliminary results presented.
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MOPCH132 | Coupled Maps for Electron and Ion Clouds | electron, ion, simulation, RHIC | 354 | ||||
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Contemporary electron cloud models and simulations reproduce second order phase transitions, in which electron clouds grow smoothly beyond a threshold from "off" to "on". In contrast, some locations in the Relativistic Heavy Ion Collider (RHIC) exhibit first order phase transition behaviour, in which electron cloud related outgassing rates turn "on" or "off" precipitously. This paper presents a global framework with a high level of abstraction in which additional physics can be introduced in order to reproduce first (and second) order phase transitions. It does so by introducing maps that model the bunch-to-bunch evolution of coupled electron and ion clouds. This results in simulations that run several orders of magnitude faster, reproduce first order phase transitions, and show hysteresis effects. Coupled maps also suggest that additional dynamical phases (like period doubling, or chaos) could be observed.
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MOPCH138 | Choice of Proton Driver Parameters for a Neutrino Factory | target, factory, beam-loading, acceleration | 372 | ||||
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A Neutrino Factory typically comprises the following subsystems: proton driver; target; muon collection and conditioning( bunching, phase rotation, and cooling); muon acceleration; and muon decay ring. It takes great effort to design each subsystem properly, such that it can mesh with all other subsystems to optimize the overall facility performance. This optimization is presently being studied as part of the International Scoping Study of a Future Neutrino Factory and Superbeam Facility. This paper will evaluate the implications of other subsystems on the parameters of a proton driver for a Neutrino Factory. At the desired power of 4 MW, the impacts of the choice of the proton energy, bunch length, bunch intensity, and repetition rate on other subsystems are assessed to identify a proper range of operation for each parameter. A suitable "design phase space" of proton driver parameters is defined. Given possible choices of design parameters for proton driver, we compare the performance of a linac, a synchrotron, and an FFAG accelerator. The relative merits of existing proton driver proposals will also be examined.
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MOPCH165 | Low- and Intermediate-beta, 352 MHz Superconducting Half-wave Resonators for High Power Hadron Acceleration | hadron, acceleration, linac, vacuum | 448 | ||||
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A beta=0.17, 352 MHz superconducting Half-Wave resonator was designed and constructed at INFN-LNL in the framework of the SPES and EURISOL projects. This cavity, together with the beta=0.31 HWR of similar design that was previously built in the framework of the SPES project, allows acceleration of high power hadron beams in the 5?100 MeV/u energy range, as required in the SPES primary linac and in the first part of the EURISOL proton driver. Main features of this structure, compared to other ones developed elsewhere with different geometries for similar applications, are compactness and mechanical stability. Characteristics and test results will be presented.
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MOPLS007 | Monitoring Heavy-ion Beam Losses in the LHC | ion, LHC, simulation, collimation | 544 | ||||
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The LHC beam loss monitor (BLM) system, primarily designed for proton operation, will survey particle losses and dump the beam if the loss rate exceeds a threshold expected to induce magnet quenches. Simulations of beam losses in the full magnet geometry allow us to compare the response of the BLMs to ion and proton losses and establish preliminary loss thresholds for quenches. Further simulations of beam losses caused by collimation and electromagnetic interactions peculiar to heavy ion collisions determine the positions of extra BLMs needed for ion operation in the LHC.
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MOPLS009 | The LHC as a Proton-nucleus Collider | LHC, ion, injection, SPS | 550 | ||||
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Following its initial operation as a proton-proton (p-p) and heavy-ion (208Pb82+ - 208Pb82+) collider, the LHC is expected to operate as a p-Pb collider. Later it may collide protons with other lighter nuclei such as 40Ar18+ or 16O8+. We show how the existing proton and lead-ion injector chains may be efficiently operated in tandem to provide these hybrid collisions. The two-in-one magnet design of the LHC main rings imposes different revolution frequencies for the two beams in part of the magnetic cycle. We discuss and evaluate the consequences for beam dynamics and estimate the potential performance of the LHC as a proton-nucleus collider.
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MOPLS014 | Lifetime Limit from Nuclear Intra-bunch Scattering for High-energy Hadron Beams | scattering, LHC, ion, injection | 565 | ||||
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We derive an approximate expression for the nuclear scattering rate inside a bunched hadron beam. Application to the LHC suggests that the loss rate due to nuclear scattering can be significant in high-energy proton or ion storage rings.
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MOPLS022 | On the Feasibility of Polarized Heavy Ions in RHIC | ion, RHIC, resonance, heavy-ion | 586 | ||||
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Heavy nonspherical ions such as uranium have been proposed for collisions in RHIC. When two such ions collide with their long axes aligned, then the plasma density might be as much as 60% higher. Since the collisions might have any orientation of the two nuclei, the alignment of the nuclei must be inferred from a complicated unfolding of multiplicity distributions. Instead, if it is possible to polarize the ions and control the orientation in RHIC, then a much better sensitivity could be obtained. This paper investigates the manipulation of such polarized ions with highly distorted shapes in RHIC. Several ion species are considered as possibilities with either full or partial Siberian snakes in RHIC.
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MOPLS025 | Experience in Reducing Electron Cloud and Dynamic Pressure Rise in Warm and Cold Regions in RHIC | emittance, electron, RHIC, luminosity | 595 | ||||
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Significant improvement has been achieved for reducing electron cloud and dynamic pressure rise at RHIC over several years; however, there remain to be factors limiting luminosity. The large scale application of non-evaporable getter (NEG) coating in RHIC has been proven effective in reducing electron multipacting and dynamic pressure rise. This will be reported together with the study of the saturated NEG coatings. Since beams with increased intensity and shorter bunch spacing became possible in operation, the electron cloud effects on beam, such as the emittance growth,are an increasing concern. Observations and studies are reported. We also report the study results relevant to the RHIC electron cloud and pressure rise improvement, such as the effect of anti-grazing ridges on electron cloud in warm sections, and the effect of pre-pumping in cryogenic regions.
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MOPLS054 | On Increasing the HERA Luminosity | luminosity, lepton, optics, electron | 667 | ||||
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The luminosity of the HERA lepton proton collider is limited in part by the bunch length of the protons of 20cm. This limitation is expected to be removed by the installation of a new damper system which will control longitudinal coupled bunch instabilities of the proton beam and avoid the bunch lengthening of a factor of two. This opens the possibility for increasing the luminosity HERA since the beta functions at IP for both leptons and protons can be lowered by about 20% without noticeable reduction of the corresponding luminosity by the so-called hour-glass effect. The beam spot size can be further reduced if the beam-beam focusing of the leptons (dynamic beta) at IP is increased by softening the rigorous beam beam-beta beat compensation which is accomplished by proper phasing of the two IP's. Unfortunately the non-linear chromaticity compensation would be weakened as well, which will cause an enhancement of the synchro-betatron resonances and may lead to poor lifetime and poor background conditions. Therefore, the non-linear chromaticity needs to be reduced by means of a more complex scheme of chromaticity compensating sextupole magnets.
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MOPLS055 | A Lepton-proton Collider with LHC | lepton, luminosity, LHC, collider | 670 | ||||
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The physics, and a design, of a Large Hadron Electron Collider (LHeC) are sketched. With high luminosity, 1033cm-2s-1, and high energy, ?s = 1.4TeV, such a collider can be built in which a 70GeV electron (positron) beam in the LHC tunnel is in collision with one of the LHC hadron beams and which operates simultaneously with the LHC. The LHeC makes possible deep-inelastic lepton-hadron (ep, eD and eA) scattering for momentum transfers Q2 beyond 106GeV2 and for Bjorken x down to the 10-6. New sensitivity to the existence of new states of matter, primarily in the lepton-quark sector and in dense partonic systems, is achieved. The precision possible with an electron-hadron experiment brings in addition crucial accuracy in the determination of hadron structure, as described in Quantum Chromodynamics, and of parton dynamics at the TeV energy scale. The LHeC thus complements the proton-proton and ion programmes, adds substantial new discovery potential to them, and is important for a full understanding of physics in the LHC energy range.
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Contributed to the Open Symposium on European Strategy for Particle Physics Research, LAL Orsay, France, January 30th to February 1st , 2006. hep-ex/0603016 DESY 06-00Cockcroft-06-05 |
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MOPLS058 | eRHIC - Future Machine for Experiments on Electron-ion Collisions | electron, luminosity, ion, positron | 676 | ||||
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The paper presents recent developments for the design of the high luminosity electron-ion collider, eRHIC, proposed on the basis of the existing RHIC machine. The goal of eRHIC is to provide collisions of electrons and positrons on ions and protons in the center-of-mass energy range from 30 to 100 GeV. Lepton beams as well as the beam of protons (and, possibly, light ions) should be polarized. Two independent designs are under development, the so-called 'ring-ring' and 'linac-ring' options. The 'ring-ring' option is based on a 10 GeV electron storage ring. The design issues for the 'ring-ring' option are similar to those at existing B-factories. In the 'linac-ring' option, the electron beam is accelerated in a 10 GeV recirculating energy recovery linac. This option may provide higher luminosities (> 1·1033 cm-2s-1 for e-p collisions), but requires considerable R&D studies for a high current electron polarized source. In order to maximize the collider luminosity, ion ring upgrades, such as electron cooling and ion beam intensity increase, are considered.
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TUXPA01 | Tevatron Operational Status and Possible Lessons for the LHC | antiproton, optics, collider, target | 900 | ||||
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This talk will provide an overview of the Tevatron Run II luminosity progress and plans, including SC magnet measurements and modeling of field errors in view of the LHC operation, electron cooling progress and results, slip-stacking and optimized use of the injectors for antiproton production, and improvements in the antiproton source.
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Transparencies
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TUXPA02 | RHIC Operational Status and Upgrade Plans | RHIC, ion, electron, luminosity | 905 | ||||
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Since 2000 RHIC has collided, at 8 energies, 4 combinations of ion species, ranging from gold ions to polarized protons, and including the collisions of deuterons with gold ions. During that time the heavy ion luminosity increased by 2 orders of magnitude, and the proton polarization in store reached 46% on average. Planned upgrades include the evolution to the Enhanced Design parameters by 2008, the construction of an Electron Beam Ion Source (EBIS) by 2009, the installation of electron cooling for RHIC II, and the implementation of the electron-ion collider eRHIC. We review the expected operational performance with these upgrades.
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Transparencies
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TUZAPA01 | Present Status of the J-PARC Accelerator | linac, injection, quadrupole, acceleration | 930 | ||||
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The Japan Proton Accelerator Research Complex (J-PARC) is a joint project of High Energy Accelerator Research Organization (KEK) and Japan Atomic Energy Agency (JAEA), which started on April 1, 2001. The J-PARC accelerator complex is composed of a 400 MeV proton linac, a 3 GeV Rapid-Cycling Synchrotron (RCS), and a 50 GeV Proton Synchrotron (MR). A 180-MeV beam ( in the first stage) accelerated by the linac is to be injected into the RCS, and further accelerated there to 3 GeV. The RCS will operate at 25 Hz, and will provide the Materials and Life Science Facility (MLF) with a 1-MW beam (600 kW during 180 MeV injection). There are two extraction sections in the MR: fast extraction for neutrino experiment and slow extraction for the Hadron Facility. A linac beam with a peak current of 30 mA and an energy of 19.7 MeV was successfully accelerated in Sep. 2004 using the first tank of the Drift Tube Linac in KEK. Now three accelerators are under installation. The beam commissioning of the linac will start in this December and those of the RCS and the MR will start in Sep. 2007 and May 2008, respectively. Status of installation and plan for commissioning run will be presented.
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Transparencies
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TUZAPA02 | ISIS Upgrades A Status Report | synchrotron, target, linac, rfq | 935 | ||||
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Since 2002 several accelerator upgrades have been made to the ISIS spallation neutron source at the Rutherford Appleton Laboratory in the UK, and upgrades are currently continuing in the form of the Second Target Station Project. The paper reviews the upgrade programmes: a new extraction straight, replacement of the Cockcroft-Walton by an RFQ, installation of a second harmonic RF system, replacement and upgrading of installed equipment, design and installation of improved diagnostics in conjunction with beam dynamics simulations, the Second Target Station Project, design and construction of a front end test stand, and the MICE programme. The paper also looks forward to possible future schemes at ISIS beyond the Second Target Station Project.
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Transparencies
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TUZBPA02 | Crystal Channelling in Accelerators | extraction, SPS, collimation, simulation | 945 | ||||
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This presentation will begin with a description of the channelling of charged particles through crystals and the use of the channelling effect in accelerators etc. Results from use of crystals for beam deflection and extraction from synchrotrons in Russia, USA and CERN will also be given. Following this the potential advantage of crystals for collimation in high-energy high-intensity machines will be described.
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Transparencies
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TUXFI01 | FFAG Accelerators and their Applications | acceleration, focusing, target, emittance | 950 | ||||
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This talk will give an introduction to the FFAG concept and review the present development of FFAG accelerators. It will also discuss the use of FFAGs for applications such as hadron therapy, neutron generation, BNCT, ADS, and muon acceleration.
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Transparencies
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TUOAFI02 | Design of a Treatment Control System for a Proton Therapy Facility | controls, cyclotron, radiation, target | 958 | ||||
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The IUCF Proton Therapy System (PTS)is designed by Indiana University and operated by the Midwest Proton Radiotherapy Institute (MPRI) to deliver proton radiation treatment to patients with solid tumors or other diseases susceptible to radiation. PTS contains three Treatment Systems, each consisting of four subsystems: Beam Delivery, Dose Delivery, Patient Positioning and Treatments Control. These systems are implemented using different operating systems, control software, and hardware platforms. Therefore, IUCF developed an XML network communication protocol so that subsystems could issue commands to and receive feedback and status from other subsystems over a local area network (LAN). This protocol was also applied to the MPRI clinical database used to access patient treatment plans. The treatment control system was designed so that a single user interface could be used to deliver proton therapy. The use of the XML and the LAN allowed the software of the treatment control system to be designed such that the various systems are treated as objects with properties and methods. This approach not only simplified the overall design of the treatment control system, it also simplified the effort required for software validation, testing, and documentation.
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Transparencies
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TUYFI01 | Gantry Design for Proton and Carbon Hadrontherapy Facilities | ion, dipole, GSI, photon | 964 | ||||
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Using an isocentric gantry improves the efficiency and the flexibility of cancer treatments with ion beams (hadrontherapy). After an overview of the constraints imposed to these heavy equipments the gantries constructed for both proton and carbon ion facilities will be described. Finally, the new studies undertaken to decrease the cost of such equipments will presented.
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Transparencies
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TUOCFI02 | First Results of SNS Laser Stripping Experiment | laser, ion, electron, SNS | 980 | ||||
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Thin carbon foils are used as strippers for charge exchange injection into high intensity proton rings. However, the stripping foils become radioactive and produce uncontrolled beam loss, which is one of the main factors limiting beam power in high intensity proton rings. Recently, we presented a scheme for laser stripping of an H- beam for the SNS ring. First, H- atoms are converted to H0 by a magnetic field, then H0 atoms are excited from the ground state to the upper levels by a laser, and the excited states are converted to protons by a magnetic field. This paper presents first results of the SNS laser stripping proof-of-principle experiment. The experimental setup is described, and possible explanations of the data are discussed.
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Transparencies
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TUODFI01 | The Final Collimation System for the LHC | LHC, collimation, insertion, impedance | 986 | ||||
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The LHC collimation system has been re-designed over the last three years in order to address the unprecedented challenges that are faced with the 360 MJ beams at 7 TeV. The layout of the LHC has now been fixed and a final approach for collimation and cleaning has been adopted. In total 132 collimator locations have been reserved in the two LHC rings and can be installed in a phased approach. Ninety collimators of five different types will be available for initial beam operation. The system has been fully optimized for avoiding quenches of super-conducting magnets during beam losses and for sufficient survival of beamline components against radioactive dose. The phased approach for LHC collimation is described, the various collimators and their functionalities are explained, and the expected system performance is summarized.
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Transparencies
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TUPCH023 | Direct Observation of Beam-beam Induced Dynamical Beta Beating at HERA | electron, luminosity, synchrotron, synchrotron-radiation | 1046 | ||||
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The Hadron Electron Ring Anlage (HERA) at DESY provides collisions between a 920 GeV proton beam and a 27.5 GeV electron beam in two interaction regions. The strong beam-beam force, which mainly affects the electrons, induces a tune shift together with a dynamical beta beat. The latter leads to a modification of the transverse beam profile, which can be observed in different profile monitors in HERA. The time-like evolution of the electron beam shape during luminosity tuning and before and after dump of the proton beam, averaged over all bunches, could be studied by means of a synchrotron radiation profile monitor. Measurements with a wire scanner allowed to see the beam-beam force's influence on each individual bunch at the expense of resolution. The observations could be explained qualitatively in the frame of linear incoherent beam-beam interaction.
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TUPCH036 | Modelling of Diagnostics for Space Charge Studies on the ISIS Synchrotron | space-charge, ion, simulation, synchrotron | 1082 | ||||
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The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. It is based on a 50 Hz proton synchrotron which, once the commissioning of a new dual harmonic RF system is complete, will accelerate about 3.5·1013 protons per pulse from 70 to 800 MeV, corresponding to mean beam powers of 0.2 MW. Transverse space charge is a key issue for both present and proposed upgrades to the machine, and is the focus of current R&D studies. Experiments on the ISIS ring are central to this work, therefore understanding and quantifying limitations in present and proposed diagnostics is essential. This paper presents work studying and modelling the ISIS residual gas profile monitors, including the effects of non-uniformity in sweep fields, space charge and images. Progress on related work looking at other important diagnostics, e.g., position and envelope monitoring, will also be summarised.
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TUPCH064 | Beam-based Alignment Strategy for the Group Controlled Magnets System | alignment, simulation, quadrupole, controls | 1160 | ||||
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The beam based alignment of the beam position monitor (BPM) becomes an important tool to reduce the closed orbit distortion (COD) in the recent accelerator. Normally, it requires the independent control of the quadrupole field. Changing the current of a quadrupole magnet, one would find the unperturbed position. However, the J-PARC Rapid-Cycling Synchrotron (RCS) has seven quadrupole families and only group of each family can be controlled simultaneously. There is neither separate power supplies nor auxiliary coil windings on each individual magnet. A similar alignment procedure is applicable for the coupled-controlled magnet system, but it becomes very complicated. For the simplest case, three magnets grouped together, four different beam orbits have to be measured at three different BPM locations. The method and some simulation results for J-PARC/RCS case will be presented in this report.
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TUPCH084 | Expected Signal for the TBID and the Ionization Chambers Downstream of the CNGS Target Station | target, secondary-beams, LEFT, instrumentation | 1208 | ||||
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Downstream the carbon graphite target of the CNGS (CERN Neutrinos to Gran Sasso) facility at CERN it has been decided to install a secondary emission monitor called TBID (Target Beam Instrumentation Downstream) monitor to measure the multiplicities and the left/right as well as up/down asymmetries of secondary particles from target. Calculations show that the titanium windows used to close off the TBID vacuum tank might not withstand the highest beam intensities with small spot sizes expected at CNGS, in case the proton beam accidentally misses the 4-5 mm diameter target rods. Therefore it has been suggested to place two ionisation chambers as a backup for the TBID located left and right of the TBID monitors. Monte Carlo simulations with the particle transport code FLUKA were performed firstly to obtain the fluence of charged particles in the region of interest and secondly to estimate the induced radioactivity (noise) in this area. This allows to assess the actual signal/noise situation and thus to determine the optimal position (lateral displacement with respect to the beamline) of the ionisation chambers. This document presents the results of these calculations.
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TUPCH092 | Commissioning of a New Digital BPM System for the PSI Proton Accelerators | cyclotron, pick-up, controls, instrumentation | 1226 | ||||
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A new digital beam position monitor (DBPM) system has been developed and successfully tested at the PSI proton accelerators. The DBPM hardware consists of an analogue RF front-end (RFFE), a VMEbus backplane module (VBM), and the PSI VME PMC Carrier board (VPC). The RFFE combines the 2nd RF harmonic (101.26 MHz) beam signals of pickup coils with a 101.31 MHz pilot signal. The RFFE output signals are undersampled and down-converted to base-band (no analogue mixer) by ADCs and DDCs (Direct Digital Downconverters) on the VBM. The DDCs send the digitised beam and pilot signal amplitudes to a Virtex2Pro FPGA on the VPC board. The FPGA calculates the beam positions at different averaging rates, checks interlock limits, and provides triggered storage of beam position waveforms. Furthermore, the FPGA performs automatic gain control of voltage-controlled amplifiers (VCAs) of RFFE and VBM. By continuous normalisation of beam to pilot signal, nonlinearities and temperature drifts of the electronics are eliminated. Compared to the old analogue BPM electronics, the new DBPMs offer an increased dynamic range (0.2 μA to 2 mA instead of 5 μA to 2 mA) and larger bandwidth (10 kHz instead of 10 Hz).
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TUPCH115 | Status of the 70 MeV, 70 mA CH Proton-DTL for FAIR | quadrupole, GSI, impedance, antiproton | 1283 | ||||
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The CH-type cavity shows promising features in the low and medium beta range: its high accelerator gradient and the high level of shunt impedance together with the compact transverse dimensions make this new cavity a good candidate for proton acceleration up to 100 MeV. That's why GSI has decided to base the new high current proton injector for the new FAIR facility on that structure: the operating frequency will be 352 MHz with an injection energy of 3 MeV. In order to improve the technical experience on this new kind of structure, IAP has built a model consisting of 8 equidistant gaps for a total cavity-length of 60 cm. Several design options with respect to welding, alignement, cooling and RF joints were studied and compared each other. A new concept for the end-cells geometry will result in the desired flatness of the electric field along the cavity axis and, at the same time, allow effective integration of internal quadruple lenses. Finally, the electric quadruple content of CH-structure gaps is listed in dependence on the geometry of the cell.
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TUPCH131 | High Power Test of MA Cavity for J-PARC RCS | impedance, synchrotron, acceleration, power-supply | 1322 | ||||
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We have been constructing the RF system for the J-PARC RCS. Almost all of the power supplies and the tube amplifiers have been constructed, and the cavities are under construction. All of them are tested at the experimental hall before installing into the J-PARC RCS building. We test the hybrid cavity scheme to realize the optimum cavity Q-value. The results of the test are described.
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TUPCH134 | RF Characteristics of the PEFP DTL | coupling, controls, rfq, klystron | 1331 | ||||
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A conventional 20 MeV Drift Tube Linac (DTL) for the Proton Engineering Frontier Project (PEFP) has been developed as a low energy section of a 100 MeV accelerator. The 20 MeV DTL consists of 4 tanks with 152 cells. The machine has a unique feature of driving the 4 tanks with a single klystron. Therefore it has several control knobs to compensate the errors of each tank during operation. To develop the RF control scheme, the variations of the RF parameters of each tank were measured under various environmental conditions such as wall temperature, cooling water temperature, and cooling water pressure. In addition, the behaviors of the RF parameters among the tanks were also monitored during high power operation. In this paper, the measurement results are discussed and the control scheme based on the results are proposed.
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TUPCH162 | Operation Results of 1 MW RF Systems for the PEFP 20 MeV Linac | klystron, rfq, power-supply, linac | 1402 | ||||
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The PEFP 20 MeV linear accelerator is composed of a 3 MeV RFQ and 20 MeV DTL. Two sets of 1MW, 350MHz RF systems drive the RFQ and DTL. The RF system can perform a 100% duty operation. The TH2089F klystron is used as an RF source. During the test operation, only the driving RF signal of the klystron was operated in pulse mode, while the electron beam was maintained in DC mode. The klystron power supplies and cooling systems were also operated in 100% duty mode. In this paper, the operation results of 1 MW RF systems including klystron power supply and cooling system are discussed and propose possible options to improve the operation conditions based on the results.
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TUPLS016 | Characterization of Crystals for Steering of Protons through Channelling in Hadronic Accelerators | scattering, lattice, CERN, extraction | 1523 | ||||
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Channeling of relativistic particles through a crystal may be useful for many applications in accelerators, and particularly for collimation in hadronic colliders. Efficiency proved to be dependent on the state of the crystal surface and hence on the method used for preparation. We investigated the morphology and structure of the surface of the samples that have been used in accelerators with high efficiency. We found that crystal fabrication by only mechanical methods (dicing, lapping, and others) leads to a superficial damaged layer, which is correlated to performance limitation in accelerators. A planar chemical etching was studied and applied in order to remove the superficial damaged layer. RBS analysis with low-energy protons highlighted better crystal perfection at surface, as a result of the etching. Finally, measurement with 70-GeV protons at IHEP demonstrated a superior performance of the chemically cleaned crystals with respect to conventional samples. A protocol for preparation and characterization of crystal for channelling has been developed, which may be of interest for reliable operation with crystals in accelerators.
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TUPLS017 | Optics Study for a Possible Crystal-based Collimation System for the LHC | LHC, collimation, injection, extraction | 1526 | ||||
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The use of bent crystals as primary collimators has been long proposed as an option to improve the cleaning efficiency of the LHC betatron and momentum collimation systems. These systems are presently based on two-stage collimation with amorphous scatterers and absorbers. Crystals are expected to help by channeling and extracting the halo particles with large angles, resulting in higher cleaning efficiency. Independent of ongoing studies for crystal qualifications (not reported here), it is important to understand the required deflection angles and the possible locations of absorbers for the LHC layout. Optics studies have been performed in order to specify the required angles for various LHC beam energies and possible locations of absorbers for the deflected halo beam. A possible layout for crystal-assisted collimation at the LHC is discussed, aiming for a solution which would not change the LHC layout but would make use of the existing collimator location.
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TUPLS018 | Collimation Efficiency during Commissioning | collimation, LHC, insertion, betatron | 1529 | ||||
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The design of the LHC collimation system naturally focused on understanding and maximizing the ultimate performance with all collimators in place. However, for the commissioning of the LHC it is important to analyze the collimation efficiency with certain subsets of collimators, with increased collimation gaps and relaxed set-up tolerances. Special studies on halo tracking and energy deposition have been performed in order to address this question. The expected cleaning performance and intensity limits are discussed for various collimation scenarios as they might be used during commissioning and initial operation of the LHC.
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TUPLS019 | Critical Halo Loss Locations in the LHC | optics, LHC, injection, insertion | 1532 | ||||
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The requirements on cleaning efficiency in the LHC are two to three orders of magnitude beyond the needs at existing super-conducting colliders. The LHC will therefore operate in unknown territory, which can only be assessed by powerful simulation tools. Such tools have been developed at CERN over the last years, making it possible to perform detailed simulations of the LHC cleaning processes and multi-turn loss patterns around the LHC ring. The simulation includes all collimators, diluters and absorbers in the LHC. Proton loss maps are generated with a 10 cm resolution, which allows performing advanced studies for quenches of super-conducting magnets along with the analysis of the deposited energy in the machine elements. The critical locations of beam halo losses are discussed, both for the ideal machine and for various scenarios of closed-orbit distortion and beta-beating. From these results it can be shown that it is sufficient to use a limited number of BLM's for the setup and optimization of the LHC collimation system.
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TUPLS021 | First Observation of Proton Reflection from Bent Crystals | scattering, lattice, CERN, collimation | 1535 | ||||
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We recently suggested using short bent crystals as primary collimators in a two-stage cleaning system for hadron colliders, with the aim of providing larger impact parameters in the secondary bulk absorber, through coherent beam-halo deflection*. Tests with crystals a few mm long, performed with 70 GeV proton beams at IEHP in Protvino, showed a channeling efficiency exceeding 85%. We also observed disturbing phenomena such as dechanneling at large impact angle, insufficient bending induced by volume capture inside the crystal, multiple scattering of non-channeled protons and, for the first time, a proton flux reflected by the crystalline planes. Indeed, protons with a tangent path to the curved planes somewhere inside the crystal itself are deflected in the opposite direction with respect to the channeled particles, with an angle almost twice as large as the critical angle. This effect, up to now only predicted by computer simulations**, produces a flux of particles in the wrong direction with respect to the absorber, which may hamper the collimation efficiency if neglected.
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*A. Afonin et al. PhysRevLett.87.094802(2001).**A. M. Taratin and S.A.Vorobiev, Phys.Lett. A119(1987)425. |
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TUPLS022 | Experimental Study of Crystal Channeling at CERN-SPS for Beam-halo Cleaning | LHC, collimation, alignment, SPS | 1538 | ||||
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An efficient and robust collimation system is mandatory for any superconducting hadron collider, in particular for the LHC, which will store a beam of unprecedented high intensity and energy. The usage of highly efficient and short primary bent-crystal collimators might be a possibility for reaching nominal and ultimate LHC intensity. Over the last years, groups in Russia (St. Petersburg) and Italy (Ferrara) have developed crystal production methods, which considerably improve the crystal quality. In view of the crystal-collimation experiments at the Tevatron and of the potential improvement compared with the phas·10-1 LHC collimation system, considering the recent progress in crystal technology, we proposed experiments for crystal characterization in the SPS beam lines. Major objectives will be: 1) qualification of the new crystals to be used in the Tevatron; 2) measuring the channeling efficiency of long crystals with 1 mrad and/or 8 mrad bending angle; and 3) comparison of loss patterns around the ring for a crystal with one for amorphous material. In this paper we will report the progress towards the SPS experiment.
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TUPLS033 | First Stage of a 40 MeV Proton Deuteron Accelerator Commissioning Results | ion, ion-source, rfq, linac | 1562 | ||||
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In 2006 the first stage of a 40MeV superconducting linear accelerator for protons and deuterons will be commissioned at SOREQ. This paper will present commissioning of the ECR source after final assembly. First results of the 1.5MeV/u cw RFQ are expected, further test results of the beta=0.09 half wave superconducting resonators are presented, and resonator geometry improvements with respect to electron multipacting behaviour will be discussed. An outlook on the project with respect to achieve the final energy of 40MeV will be given.
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TUPLS036 | Status of the Linac-commissioning for the Heavy Ion Cancer Therapy Facility HIT | rfq, ion, GSI, linac | 1571 | ||||
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A clinical facility for cancer therapy using energetic proton and ion beams (C, He and O) is under construction and will be installed at the Radiologische Universitätsklinik in Heidelberg, Germany. It consists of two ECR ion sources, a 7 MeV/u linac injector and a 6.5 Tm synchrotron to accelerate the ions to final energies of 50-430 MeV/u. The linac comprises a 400 keV/u RFQ and a 7 MeV/u IH-DTL operating at 216.8 MHz. In this contribution the current status of the linear accelerator is reported. After first tests with 1H+ beam of the RFQ at GSI, the commissioning of the accelerator in Heidelberg has already started. The commissioning with beam is performed in three steps for the LEBT, the RFQ and the IH-DTL. For this purpose a versatile beam diagnostic test bench has been designed. It consists of a slit-grid emittance measurement device, transverse pick-ups providing for time of flight energy measurements, SEM-profile grids and different devices for beam current measurements. This paper will provide for a status report of the linac-commissioning.
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TUPLS044 | The 3D Beam Dynamics with the Space Charge in the Low and Middle Energy Super-conducting Option of HIPPI | focusing, emittance, quadrupole, simulation | 1594 | ||||
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For the low and middle energy of the High Intensity Proton Pulse Injector (HIPPI), a superconducting option is considered.The 3D beam dynamics simulation results in the slot and the finger-slot sections covering the energy range from 3 to 160 MeV are presented. The optimization aim is the increase of beam current together with the reduction of emittance growth, beam losses and costs. The slot structure is compared with the conventional spoke structure.
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TUPLS048 | Optimization Design of a Side Coupled Linac (SCL) for Protontherapy: a New Feeding Solution | linac, cyclotron, SCL, acceleration | 1603 | ||||
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It is proposed to use an SCL, starting at 30MeV, up to 230MeV. The linac consists of 25 modules (two tanks each). Twelve, 3GHz power generators, feed two modules in parallel, with the last power generator feeding the last module. The SCL is designed, assuming a mean accelerating field in the cavities of 16,5MV/m. The longitudinal and transverse beam dynamics has been studied, assuming that the input parameters (emittance, energy spread and mean current) are those of commercial 30MeV cyclotrons. The characteristics of the ejected beam were analysed: the transmittance value is largely sufficient to deliver a correct dose for therapy; the beam line activation is kept largely below allowed levels; the output energy spread is sufficiently small. The first prototype module is under construction and a second one is under design. Contacts with e2v have been established for defining an agreement, which proposes to use magnetrons as feeders for the acceleration tests. Attention was therefore paid to phase locking constraints between feeders. Theoretical studies suggest that transmittance stays constant if de-phasing is kept into values that seem attainable with magnetrons.
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TUPLS051 | Development of PEFP 20 MeV Proton Accelerator | rfq, klystron, ion-source, site | 1609 | ||||
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A 20 MeV proton accelerator has been developed as a low energy part of PEFP (Proton Engineering Frontier Project) 100 MeV accelerator. The 20 MeV accelerator consists of ion source, LEBT (Low Energy Beam Transport), 3 MeV RFQ (Radiofrequency Quadrupole) and 20 MeV DTL (Drift Tube Linac). After the field tuning and high power RF conditioning of the accelerating cavities, the first beam test of the 20 MeV accelerator is underway. During the test, the pulsed proton beam was extracted from the ion source by pulsing the high voltage power supply. Two 1.1 MW, 350MHz RF systems were used to drive the 20 MeV accelerator. The current transformers between DTL tanks and Faraday cup at the end of 20 MeV DTL were used to measure the beam current. In this paper, the development of 20MeV accelerator are summarized and the first beam test results are discussed.
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TUPLS052 | Beam Dynamics of the PEFP Linac | rfq, emittance, linac, quadrupole | 1612 | ||||
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The PEFP Linac consists of a 50 keV ion source, LEBT, 3 MeV RFQ, 20 MeV DTL called DTL1, MEBT, and 100 MeV DTL called DTL2. The MEBT includes two small DTL tanks, which match the 20 MeV proton beams into the DTL2, and a bending magnet, which extracts the 20 MeV proton beams to the experimental hall. We will present the full beam dynamics study from the entrance of the DTL1 to the end of DTL2 with the initial beam parameters obtained from a simulation study of the RFQ. Our study focuses on the longitudinal beam matching in order to compensate the missing RF effect between every neighboring DTL tanks as well as the full beam matching between DTL1 and DTL2.
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TUPLS055 | First Section of a 352 MHz Prototype Alvarez DTL Tank for the CERN SPL | quadrupole, linac, CERN, laser | 1621 | ||||
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In the Linac4/SPL projects at CERN, 352 MHz 30 mA DTL Alvarez accelerating structure will be used to accelerate protons between 3 and 40 MeV. The R&D for the development of a prototype structure for the energy range from 3 to 10 MeV is taking place jointly at ITEP and VNIIEF. The design of this 2.7 m Alvarez tank containing 27 drift tubes is described in this document. Results of calculations of the section parameters are presented. One of the main features of the design is the use of permanent magnets made of SmCo5 alloy as quadrupole focusing lenses (PMQ) inside the drift tubes. Details of the experimental PMQ-equipped drift tube are described.
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TUPLS064 | Design and Commissioning of a Compact Electron Cooler for the S-LSR | electron, cathode, gun, ion | 1639 | ||||
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The ion cooler ring S-LSR has been constructed and commissioned in October 2005. The ring successfully stored a 7 MeV proton beam. The S-LSR is equipped with a compact-electron cooler which has a cooling solenoid length of 0.8 m, a toroid bending radius of 0.25 m and maximum magnetic field in the cooling section of 0.5 kG. The commissioning of the electron cooler was carried out with successful observation of both longitudinal and horizontal cooling of the proton beam. By varying the electric potential on the Pierce electrode in the gun, we have investigated the possibility of generating a hollow shaped electron beam, and studied its effect on the electron cooling process. Also the effect of the electrostatic deflector, installed in the toroid section in order to compensate the drift motion of the secondary electrons, was investigated. The design and results of the commissioning of the compact electron cooler are presented.
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TUPLS065 | Beam Commissioning of Ion Cooler Ring, S-LSR | ion, electron, vacuum, laser | 1642 | ||||
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S-LSR is a new ion cooler ring constructed in Kyoto University. The circumference is 22.557 m and the maximum magnetic rigidity is 1 Tm. The constructiion and the vacuum baking had been finished in September, 2005. The beam commissioning was started since October, 2005. The injected beam is 7 MeV proton from the existing linac. The beam circulation test and the electron beam cooling were carried out successfully and the beam information and the characteristics of the ring were measured. One of the subjects of S-LSR is a realization of the crystalline beams using the electron and laser cooling. The lattice of S-LSR was designed to suppress the beam heating as much as possible and we also present such measurement results in this paper.
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TUPLS073 | Formulae for Linear-field Non-scaling FFAG Accelerator Orbits | lattice, betatron, ion, resonance | 1666 | ||||
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Non-scaling FFAG accelerators using constant-gradient F and D magnets with their fields decreasing outwards can compact ion orbits for a wide range of momentum (e.g., 1:2) into a narrow radial range. Designs to accelerate protons, ions and muons are currently being studied for proton drivers, cancer therapy facilities and neutrino factories. In this paper, analytic formulae are reported for some basic orbit properties, helping to make clear their dependence on the various design parameters and momentum. For the designs tested so far the numerical results are in excellent agreement with those obtained using lattice codes.
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TUPLS077 | Development of FFAG-ERIT Ring | target, storage-ring, emittance, simulation | 1675 | ||||
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An intense neutron source with the emittance recovery internal target (ERIT) using the FFAG accelerator is under development. The design of the FFAG storage ring for this purpose will be presented.
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TUPLS079 | Hadron Cancer Therapy Complex Employing Non-scaling FFAG Accelerator and Fixed Field Gantry Design | acceleration, extraction, kicker, resonance | 1681 | ||||
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Non-scaling FFAG rings for cancer hadron therapy offer reduced physical aperture and large dynamic aperture as compared with scaling FFAGs. The variation of tune with energy implies the crossing of resonances during acceleration. Our design avoids intrinsic resonances, although imperfection resonances must still be crossed. We consider a system of three non-scaling FFAG rings for cancer therapy with 250 MeV protons and 400 MeV/u carbon ions. Hadrons are accelerated in a common RFQ and linear accelerator, and injected into the FFAG rings at v/c=0.1128. The H+/C6+ ions are accelerated in the two smaller/larger rings to 31 and 250 MeV/52.5 and 400 MeV/u kinetic energy, respectively. The lattices consist of symmetrical triplet cells with a straight section for RF cavities. The gantry with similar triplet cells accepts the whole required momentum range at fixed field. This unique design uses either High Temperature super-conductors or super-conducting magnets reducing gantry size and weight. Elements with a variable field at the beginning and at the end set the extracted beam at the correct position for the specific energy and adapt the beam to specific requirements during treatment.
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TUPLS082 | The Frankfurt Neutron Source at the Stern-Gerlach-Zentrum (FRANZ) | linac, target, GSI, space-charge | 1690 | ||||
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About 40ns long proton pulses with an energy of 120keV and currents of up to 200mA will be produced at the 150kV high current injector with a rep.rate of up to 250kHz. The main acceleration will be done by a 175MHz-RFQ. After this section the proton bunches will have an energy of about 1.7MeV. A 4-gap cavity will allow for an energy increase up to 2.2MeV.In order to get 1ns short pulses at the Li-7-Target we propose a buncher-system of the Mobley-Type*, whereby periodic deflection at one focus of a dipole-magnet guides the bunche train from the linac on different paths to the other focus, where the n-production traget is located in the time focus.By 7Li(p,n)B·107 reactions low-energy neutron bunches will be produced with an averaged integrated flux-density of 4*107/(cm2 s) at a distance of 0.4m. The upper limit for the neutron spectra will be 500keV. The main challange with respect to this buncher is the strong space charge action, which has to be treated by careful particle simulations. FRANZ is among other duties well suited for (n,gamma)-cross-sectional measurements with astrophysical relevance**/***. It is characterised by high n-intensities and by its pulse-structure.
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*Phys. Rev. 88(2), 360-361 (1951). **Phys. Rev. C 71, 025803 (2005).***Phys. Rev. Lett. 94, 092504 (2005). |
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TUPLS084 | Estimation of Decay Losses and Dynamic Vacuum for the Beta-beam Accelerator Chain | ion, vacuum, acceleration, SPS | 1696 | ||||
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The beta-beam is based on the acceleration and storage of radioactive ions. Due to the large number of ions required and their relatively short lifetime, beam losses are a major concern. This paper estimates the decay losses for the part of the accelerator chain comprising the CERN PS and SPS machines. For illustration purposes, the power deposition in these accelerators is compared to that expected for nominal CNGS proton operation. The beam losses induced vacuum dynamics is simulated and the consequences for machine operation are discussed.
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TUPLS094 | Development of a Permanent Magnet Microwave Ion Source for Medical Accelerators | ion, permanent-magnet, ion-source, linac | 1723 | ||||
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A permanent magnet microwave ion source was developed to improve availability of proton accelerator application systems based on industrial microwave ion source technologies. The ion source needs no filament in the discharge chamber, which leads to reliability improvement and less maintenance time. Because the ion source uses a permanent magnet, the ion source needs no coils, no coil power and no coil coolant. The hydrogen beam of over 60 mA has been extracted from a single 5mm diameter aperture with a proton fraction of 85% at a microwave power of 1.3kW. Rise times of the microwave power and beam current to 90 % of the final value were about 30 and 100μseconds respectively at a pulse operation mode with 400μseconds pulse width and 20 Hz repetition rate. These performance parameters are equal to the solenoid coil ion source parameters, making the ion source desirable for accelerator applications like proton therapy systems.
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TUPLS110 | Measurement of the Extraction Kicker System in J-PARC RCS | kicker, vacuum, extraction, LEFT | 1759 | ||||
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Kicker magnet system in the J-PARC RCS is now under construction at JAEA (Japan Atomic Energy Agency). Their role in RCS is to kick the accelerated 3 GeV proton beam to the following extraction line at a repetition rate of 25 Hz. There are three kinds of kicker magnets (S, M, L), distinguished by the difference in the size of their apertures. The specification of 2 % is required on the magnetic field in terms of homogeneity in time and space from the beam optical point of view. The required flatness of the temporal uniformity was accomplished by superposing the waveforms of the two kicker magnet*. The required specification to the special uniformity is also very severe to achieve because our kicker magnet is designed with a large aperture in order to accept a maximum beam power of 1 MW. We established the search coil as a detector and 3-axes stage to perform magnetic field mapping. In order to reduce the signal noises and detect the stable output signals, matching register and integrated circuit were carefully selected. The 3-axes stage was precisely aligned. The distribution of the magnetic field (By) and integrated BL were systematically measured for the three types of kickers.
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*J. Kamiya et al. Magnetic field measurement of the extraction kicker magnet in J-PARC RCS, submitted for publication to the proceedings of the 19th International Conference on Magnet Technology. |
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TUPLS112 | Present Status of Injection and Extraction System of 3 GeV RCS at J-PARC | injection, extraction, vacuum, emittance | 1765 | ||||
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The injection and extraction system for 3GeV RCS (Rapid Cycling Synchrotron) at J-PARC (Japan Proton Accelerator Research Complex) have many challenging issues, in order to realize MW beam in the RCS ring. The system is consisted in 3 parts, such as the injection line, the dump line, and the extraction line. And they are constructed from many kinds of components, such as DC and pulse magnets, a charge exchange system, beam monitors, titanium and ceramic vacuum chamber, a beam dump, and so on. Up to now, final designs are accomplished and developments and experiments of some components are carried out. In this presentation, summary of the injection and extraction system, recent status of developments, and beam commissioning scheme for beam injection and extraction are introduced.
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TUPLS118 | Injection System Design for the CSNS/RCS | injection, emittance, electron, linac | 1783 | ||||
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The CSNS injection system is designed to take one uninterrupted long drift in one of the four dispersion-free straight sections to host all the injection devices. Painting bumper magnets are used for both horizontal and vertical phase space painting. Closed-orbit bumper magnets are used for facilitating the installation of the injection septa and decreasing proton traversal in the stripping foil. Even with large beam emittance of about 300 pmm.mrad used, BSNS/RCS still approaches the space charge limit during the injection/trapping phase for the accumulated particles of 1.9*1013 and at the low injection energy of 80 MeV. Uniform-like beam distribution by well-designed painting scheme is then obtained to decrease the tune shift/spread. ORBIT code is used for the 3D simulations. Upgrading to higher injection energy has also been considered.
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TUPLS123 | Design of the LHC Beam Dump Entrance Window | LHC, kicker, vacuum, CERN | 1792 | ||||
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7 TeV proton beams from the LHC are ejected through a 600 m long beam dump transfer line vacuum chamber to a beam dump block. The dump block is contained within an inert gas-filled vessel to prevent a possible fire risk. The dump vessel and transfer line are separated by a 600 mm diameter window, which must withstand both the static pressure load and thermal shock from the passage of the LHC beam. In a previous paper* the functional requirements and conceptual design of this window were outlined. This paper describes the analysis leading to the final design of the window. The choice of materials is explained and tests performed on the prototype window are summarized.
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*A. Presland et al. "A large diameter entrance window for the LHC beam dump line". Proc. PAC 2005, 1698-1700. |
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TUPLS126 | Interaction of the CERN Large Hadron Collider (LHC) Beam with Carbon Collimators | LHC, target, simulation, heavy-ion | 1798 | ||||
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The LHC will operate at 7 TeV with a luminosity of 1034 cm-2s-1. Each beam will have 2808 bunches, with nominal intensity per bunch of 1.1x1011 protons. The energy stored in each beam of 362 MJ. In a previous paper the mechanisms causing equipment damage in case of a failure of the machine protection system was discussed, assuming that the entire beam is deflected into a copper target. Another failure scenario is the deflection of beam into carbon material. Carbon collimators and beam absorbers are installed in many locations around the LHC to diffuse or absorb beam losses. Since their jaws are close to the beam, it is very likely that they are hit first when the beam is accidentally deflected. Here we present the results of two-dimensional hydrodynamic simulations of the heating of a solid carbon cylinder irradiated by the LHC beam with nominal parameters, carried out using the BIG-2 computer code* while the energy loss of the 7 TeV protons in carbon is calculated using the well known FLUKA code**. Our calculations suggest that the LHC beam may penetrate up to 10 m in solid carbon, resulting in a substantial damage of collimators and beam absorbers.
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*V. E. Fortov et al. Nucl. Sci. Eng. 123 (1996) 169. **A. Fasso et al. The physics models of FLUKA: status and recent development, CHEP 2003, La Jolla, California, 2003. |
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TUPLS127 | Permanent Deformation of the LHC Collimator Jaws Induced by Shock Beam Impact: an Analytical and Numerical Interpretation | LHC, CERN, collimation, simulation | 1801 | ||||
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Inspections carried out on jaws of the LHC collimator prototype, which underwent the 450 GeV robustness test in CERN TT40 extraction line, revealed no visible damage, except a permanent deformation of the jaw metal support of ~300 um. An explanation of this phenomenon is proposed in this paper. The temperature increase on the metal support induced by the thermal shock, though limited to ~70°C, led to a sudden expansion of the copper-based support which was partially prevented by the inertia of the material itself, thus generating compressive stresses exceeding the elastic limit of OFE-copper. An analytical assessment of the process, followed by a finite-element transient elasto-plastic analysis, is presented. Numerical results are in good agreement with measured data. In order to confirm this analysis, a special test on series production jaws, where OFE-copper has been replaced by Dispersion Strengthened Copper (Glidcop®), is scheduled for the second half of 2006.
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TUPLS128 | A New Analytical Method to Evaluate Transient Thermal Stresses in Cylindrical Rods Hit by Proton Beams | target, CERN, simulation, LHC | 1804 | ||||
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This paper presents an analytical solution for the thermo-mechanical problem of CNGS target rods rapidly heated by fast extracted high energy proton beams. The method allows the computation of the dynamic transient elastic stresses induced by a proton beam hitting off-axis the target. The studies of such dynamic thermo-mechanical problems are usually made via numerical methods. However, an analytical approach is also needed to quickly provide reference solutions for the numerical results. An exact solution for the temperature field is first obtained, using Fourier-Bessel series expansion. Quasi-static thermal stresses are then computed as a function of the calculated temperature distribution, making use of the thermoelastic displacement potential for the equivalent isothermal two-dimensional stress problem. Finally, the contribution of dynamic stresses due to longitudinal and bending stress waves is determined by means of the modal summation method. This method can be effectively applied to any solid having cylindrical shape, made out of isotropic elastic material.
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TUPLS129 | EURISOL 100 kW Target Stations Operation and Implications for its Proton Driver Beam | target, EURISOL, SNS, ion | 1807 | ||||
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Targets for the next generation radioactive ion beam (RIB) facilities (RIA, EURISOL) will be subjected to energy deposition levels that call for a specific design of the target and ion source assembly to dissipate the deposited heat and to extract and ionize isotopes of interest efficiently. EURISOL, the next generation European RIB facility, plans to operate four target stations in parallel, three 100 kW direct targets and one 5 MW spallation neutron source with a GeV proton linac driver. The nature of the beam sharing has yet to be defined because in practice it will have a direct impact on target design, operation and lifetime. Splitting the beam in time implies that each target would be subjected to a pulsed beam, whose pulse width and repetition cycle have to be optimized in view of the RIB production. The 100 kW targets are expected to have a goal lifetime of three weeks. Target operation from the moment it is installed on a target station until its exhaustion involves several phases during which the incident proton beam intensity will vary. This paper discusses challenges for high power targetry at EURISOL, with an emphasis on requirements for the proton linac parameters.
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TUPLS130 | Comparison between Measured and Simulated Beam Loss Patterns in the CERN SPS | SPS, simulation, LHC, beam-losses | 1810 | ||||
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A prototype of an LHC collimator has been tested with proton beams at the CERN SPS. The interaction of the circulating proton beam with the carbon collimator jaws generated showers that were lost in the downstream SPS aperture. The measured beam loss patterns are compared in detail with the results of dedicated loss simulations. The simulation package includes (1) a 6D particle tracking through the SPS lattice; (2) the scattering interaction of protons with the collimator jaw material; (3) the time-dependent displacement of the collimator jaws with respect to the beam orbit; (4) a detailed aperture model of the full SPS ring. It is shown that the simulation tools can reliably predict the measured location of losses. This provides an important assessment of the simulation tools in view of the LHC beam loss studies.
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TUPLS133 | Material Irradiation Damage Studies for High Power Accelerators | target, BNL, AGS, controls | 1816 | ||||
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High-performance targets intercepting multi MW proton beams are the key toward intense muon or neutrino beams. To achieve this goal one must push the envelope of the current knowledge on material science and material endurance and survivability to both short and long proton beam exposure. The demand imposed on the targets of high power accelerators and the limitations of most materials in playing such pivotal roles have led to an extensive search and experimentation with new alloys and composites. These new high-performance materials and composites, which at first glance, appear to possess the right combination of properties satisfying target requirements, are explored under accelerator target conditions where both shock and irradiation damage are at play. Results of the on-going, multi-phased experimental effort under way at BNL involving heavy irradiation of candidate materials using 200 MeV protons at the end of the BNL Linac as well as results on post-irradiation analysis assessing irradiation damage are presented.
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WEOBPA01 | First Results of the CRFQ Proof of Principle | rfq, quadrupole, radio-frequency, impedance | 1873 | ||||
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The Circular Radiofrequency Quadrupole 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 Radiofrequency Quadrupole completely bent on a circle. The advantages, which are expected to be the same performance features of a linear RFQ, would be smaller overall dimension with respect to accelerators with comparable beam intensity and emittance*. A collaboration between BNL and Italian research institute and universities was set up at the end of 2002 with the aim of the proof of the bending principle**. The prototype design is based on a 4-rods scheme and have a linear sector followed by a 45-degree curved sector. The 1mA proton beam, produced by a reconditioned RF source, go through a beam gap diameter of 10mm with circular 10mm diameters rods. Each sector is 700mm long and is placed in a 150mm diameter pipe***. The RF power at 202.56MHz is fed by a CERN "Frank James" 50kW amplifier. In this paper the first power and beam tests of the linear sector are presented.
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*A.G. Ruggiero, C-A/AP/65 note, Brookhaven National Laboratory, October 2001. **A.G. Ruggiero et al., Proceedings of the EPAC 2004 conference.***D. Davino et al., Proceedings of the EPAC 2004 conference. |
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Transparencies
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WEXFI02 | Observation and Modeling of Electron Cloud Instability | electron, RHIC, KEK, LHC | 1887 | ||||
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This presentation will review experimental results and the state of the art in the analysis and simulation of the electron cloud instability in hadron and positron storage rings.
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Transparencies
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WEIFI01 | How to Create a Business out of Manufacturing Linacs | linac, ion, synchrotron, cyclotron | 1911 | ||||
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AccSys Technology, Inc. was established in 1985 by the author and several colleagues to sell ion linacs based on the new linac technology that had just been developed at the Los Alamos National Laboratory. The company is now the leading manufacturer of turn-key ion linacs for several markets worldwide. This paper will describe the history of AccSys and how it has survived more than 20 years manufacturing these specialized products. The similarities of AccSys' history to that of a small electron linac manufacturer established in 1970 will also be described to provide a general concept of what is required to create a business out of manufacturing linacs.
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Transparencies
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WEPCH007 | Beam Dynamics Studies for the Spiral-2 Project | ion, SPIRAL2, linac, dipole | 1930 | ||||
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The SPIRAL-2 superconducting linac driver, which aims to deliver 5 mA, 20 A.MeV deuterons and 1 mA, 14.5 A.MeV q/A=1/3 heavy ions, is now entering the construction phase. It is composed of an injector composed of two ECR sources entering a 88 MHz RFQ, followed by a superconducting section based on independently phased quarter-wave cavities with warm focusing. This paper presents the status of the beam dynamics studies recently performed during this construction phase: consolidation and freezing of the linac design, update of the mass separation system or analysis of the proton capability.
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WEPCH032 | Orbit Correction System for S-LSR Dispersion-free Mode | closed-orbit, kicker, electron, ion | 1993 | ||||
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An ion storage ring S-LSR has been constructed at ICR, Kyoto Univ. It is a small ring with 22.557m circumference, and has an electron cooler and laser cooling section to achieve crystalline beam. In the commissioning process, closed orbit correction of a 7MeV proton beam has been successfully realized by means of Simplex Method. Responses to the correctors are linear only within narrow limits because of the space-charge effect in the electron cooler. Therefore, the correction must be repetition of small corrections. Under such condition, measured COD has been reduced less than 0.1mm. Orbit correction is necessary for 35keV Mg+ dispersion-free mode* using both bending magnets and electrostatic deflectors. Since electrostatic deflectors have relatively large field errors, it needs a special process to inject the beam into the dispersion-free mode ring. First circulation is under only the magnetic field, then, the electric field will be added little by little applying continuous COD correction. In this way the dispersion gradually diminishes with keeping stable orbit. In this paper we present the correction scheme and the trial to the dispersion-free circulation.
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*M. Ikegami et al. Phys. Rev. ST-AB, 7, 120101-1 (2004). |
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WEPCH053 | Peculiarities of Influence of Coherency Processes at Charged Particles Channeling on Particle Beams Characteristics | positron, controls, electron | 2041 | ||||
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In the work the length of reciprocal coherency existence and peculiarities of coherency of different states of channeled particles wave functions are discussed. It was shown that the length of coherent channeling depends on the monochromaticity of initial particle beam as well as on the interaction of channeled particles with thermal oscillations of the crystal lattice. Peculiarities of influence of coherency processes at relativistic and nonrelativistic charged particles channeling on spatial and angular characteristics of particle beam that has passed through a thin crystal are discussed. In was shown, that the influence of different particle states interference within the area of coherent channeling leads to very strong periodic dependence of final beam angular width from the crystal length. This effect allows to control beam parameters (e.g., to form narrower beam, that it was before falling on the crystal). Influence of coherency of particle states in a single channel and several channels on the angular distribution and the possibility of quasicharacteristic short-wave spontaneous and stimulated radiation is also studied.
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WEPCH065 | Lattices for High-power Proton Beam Acceleration and Secondary Beam Collection, Cooling, and Deceleration | lattice, synchrotron, secondary-beams, dipole | 2074 | ||||
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Rapid-cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics b) long straight sections for low-loss injection, extraction, and high-efficiency collimation c) dispersion-free straights to avoid longitudinal-transverse coupling, and d) momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.
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WEPCH118 | LORASR Code Development | linac, rfq, simulation, space-charge | 2194 | ||||
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LORASR is specialized on the beam dynamics design of Separate Function DTL's based on the 'Combined 0 Degree Structure (KONUS)' beam dynamics concept. The code has been used for the beam dynamics design of several linacs already in operation (GSI-HLI, GSI-HSI, CERN Linac 3, TRIUMF ISAC-I) or scheduled for the near future (Heidelberg Therapy Injector, GSI Proton Linac). Recent code development was focused on the implementation of a new PIC 3D FFT space charge routine, facilitating time-efficient simulations with up to 1 million macro particles routinely, as well as of tools for error study and loss profile investigations. The LORASR code was successfully validated within the European HIPPI Project activities: It is the Poisson solver benchmarking and the GSI UNILAC Alvarez section tracking comparison programme. The error study tools are a stringent necessity for the design of future high intensity linacs. The new LORASR release will have a strong impact on the design of the GSI FAIR Facility Proton Linac, as well as the transmission investigations on the IFMIF Accelerator. This paper presents the status of the LORASR code development and the benchmarking results.
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WEPCH157 | Design and Beam Dynamics Simulation for the Ion-injector of the Austrian Hadron Therapy Accelerator | ion, simulation, synchrotron, extraction | 2296 | ||||
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MedAustron is an initiative for the construction of the Austrian Hadron Therapy Centre. In 2004 the design study was presented. The basic design consists of two ion sources, an ion-injector, a synchrotron and a beam transfer line with five possible beam exits. The synchrotron is based on the proton ion medical machine study (PIMMS) design with some modifications. The injector is based on the GSI design of the Heidelberg ion therapy cancer accelerator with the original radio frequency quadrupole and IH-Linac. Modifications have been done in the design of the low energy beam transport and the medium energy beam transport lines. The impact of these modifications has been investigated, and several other beam scenarios have bean simulated with different simulation codes.
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WEPCH158 | Status of the Hadrontherapy ETOILE-Project in Lyon | ion, radiation, GSI, hadron | 2299 | ||||
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The ETOILE project is the French program for carbon ion beams in cancer treatment. It is now in the final phase. However its development is not only aiming at the building of a medical facility, around the project a broad set of medical and scientific programs have been initiated. The project has been supported by the University of Lyon and extended to the Rhône-Alpes Region and then gained a national visibility with governmental recognition. Many studies have been financed by ETOILE: in beam PET with new solutions, organ motion modelization, tumor cell radioresistance, medico-economical simulation and epidemiological previsions. The facility will be able to produce carbon ion beams and protons. Three treatment rooms are planned, two with horizontal beams and one with an isocentric gantry. The facility will be build in Lyon, through a process using as much as possible well established technology with the other facilities in Europe. The cost will be around 105 M€ afforded by loans and subventions. The subventions are funded from the Rhône-Alpes Region, the city of Lyon and the ministries of Health and Research. The running cost of the centre, for one thousand patients per year, is estimated to be 21 M€.
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WEPCH159 | Accelerator Systems for Particle Therapy | synchrotron, ion, GSI, beam-transport | 2302 | ||||
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Danfysik and Siemens have entered a cooperation to market and build Particle Therapy* systems for cancer therapy. The systems are based on the experience from GSI together with a novel design of a synchrotron and Siemens experience in oncology. The accelerator systems will include an injector system (7 MeV/u proton and light ions), a synchrotron and a choice of fixed-angle horizontal and semi-vertical beamlines together with gantry systems. The slowly extracted beam will cover the energy ranges of 48-250 MeV for protons and 88-430 MeV/u for carbon ions. The extraction time will be up to 10s with intensities well beyond the needs of scanning beam applications. We will describe the layout of such a system and present details on some of the subsystems.
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*Particle Therapy is a work in progress and requires country-specific regulatory approval prior to clinical use. |
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WEPCH161 | The FFAG R&D and Medical Application Project RACCAM | lattice, acceleration, electron, synchrotron | 2308 | ||||
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The RACCAM project (Recherche en ACCelerateurs et Applications Medicales) has recently obtained fundings, extending over three years (2006-2008), from the French National Research Agency (ANR). RACCAM is a tripartite collaboration, involving (i) the CNRS Laboratory IN2P3/LPSC, (ii) the French magnet industrial SIGMAPHI, and (iii) the nuclear medecine Departement of Grenoble Hospital. The project concerns fixed field alternating gradient accelerator (FFAG) research on the one hand, and on the other hand their application as hadrontherapy and biology research machines. RACCAM's goal is three-fold, (i) participate to the on-going international collaborations in the field of FFAGs and recent concepts of "non-scaling" FFAGs, with frames for instance, the Neutrino Factory (NuFact) and the EMMA project of an electron model of a muon FFAG accelerator, (ii) design, build and experiment a prototype of an FFAG magnet proper to fulfil the requirements of rapid cycling acceleration, (iii) develop the concepts, and show the feasibility, of the application of such FFAG beams to hadrontherapy and to biology research.
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*CEA/DAPNIA and IN2P3/LPSC **IN2P3/LPSC ***Grenoble University Hospital ****SIGMAPHI |
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WEPCH164 | High Power RF Tests of the First Module of the TOP Linac SCDTL Structure | linac, coupling, booster, impedance | 2313 | ||||
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The TOP Linac (Oncological Therapy with Protons), under development by ENEA and ISS, is a sequence of three pulsed (5 microseconds, 300 Hz) linear accelerators: a 7 MeV, 425 MHz RFQ+DTL (AccSys Model PL-7), a 7-65 MeV, 2998 MHz Side Coupled Drift Tube Linac (SCDTL), and a 65-200 MeV, variable energy 2998 MHz Side Coupled Linac (SCL). The first SCDTL module structure, composed by nine DTL tanks coupled by eight side cavities, has been built. Low power RF measurements have shown good field uniformity and stability along the axis. The structure has been tested with a 1 - 4 MW power RF. Results of low and high power tests are reported and discussed.
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WEPCH165 | A Nonlinear Transport Line for the Optimization of F18 Production by the TOP Linac Injector | target, octupole, linac, quadrupole | 2316 | ||||
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The injector of the TOP Linac (Oncological Therapy with Protons), under development by ENEA and ISS, consists of a 7 MeV, 425 MHz RFQ+DTL (AccSys Model PL-7). It is actually in operation at ENEA-Frascati Laboratories for the production of the positron-emitting radionuclide F18 for PET analyses by an intense proton beam (8 - 10 mA, 50 - 100 μs, 30 - 100 Hz). At the exit of the injector, the beam is guided through a magnetic channel to a target composed by a thin chamber (0.5 mm thick and 1-inch diameter) containing water enriched with O18. Recently, to the original quadrupole transport channel, a non-linear magnet system using octupoles has been added in order to flatten the proton beam distribution and optimize the radioisotope production. In the paper the details of the octupole design and beam dynamic study and the first measurements results are presented.
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WEPCH173 | The Performance of Double-grid O-18 Water Target for FDG Production | target, cyclotron, radiation, simulation | 2337 | ||||
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The main stream of our study about the target is increasing the lifetime of the target windows. Mainly we conduct our study to increase the cooling performance and secondly about the structural design of the targets and target window foils. We already had developed and had published the results of our research about O-18 double-grid water target, which had installed on our 13 MeV cyclotron KIRAMS-13. The beam size of the accelerated proton was 9 mm*18 mm (0.35 in * 0.7 in). The double-grid target shows relatively low pressure during irradiation and good yield of F-18. The average yield of F-18 after irradiation was more than 1 Ci at 12.5 MeV , around 26 μA. Additionally, we are conducting new research for new techniques to increase the performance of low energy double-grid target and a new state-of-the-art pleated double foil target.
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WEPCH179 | The Indiana University Proton Therapy System | cyclotron, rfq, controls, radiation | 2349 | ||||
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The Midwest Proton Radiotherapy Institute (MPRI)was designed by the Indiana University Cyclotron Facility (IUCF)to deliver proton radiation treatment to patients with solid tumors or other diseases susceptible to radiation. The IUCF Proton Therapy System (PTS)has five unigue subsystems to perform the radiation treatment; Beam Delivery, Dose Delivery, Patient Positioning and Treatment Control systems. The MPRI Clinic began operations in 2003 with a single Fixed Horizontal Beam Line (FHBL)treatment room and is being expanded to include two additional treatment rooms utilizing modified IBA* 360 degree rotating gantry systems. The Gantry nozzles use a beam wobbling and energy stacking system to produce the lateral and longitudinal beam distributions required for patient treatment. A treatment control system** provides a single user interface to deliver and monitor Proton Therapy treatment. This paper will present an brief overview of the Proton Therapy Facility, the properties and examples of the beam performance of the unique Nozzle design, and a summary of the facility beam operations.
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* Ion Beam Applications, Inc, Belgium ** Design of a Treatment Control System for a Proton Therapy Facility, Joe Katuin, these proceedings |
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WEPCH186 | Present Status of FFAG Accelerators in KURRI for ADS Study | controls, acceleration, booster, ion | 2367 | ||||
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KART (Kumatori Accelerator driven Reactor Test) project is in progress at the Kyoto University Research Reactor Institute (KURRI) since fiscal year 2002. We are now constructing a 150 MeV proton FFAG accelerator complex as a neutron production driver for this project. The whole of this FFAG complex is expected to be in the test operation around the spring in 2006. The developments and the current status of this accelerator complex, including the current status of this project, will be presented.
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WEPCH189 | Design of the 20 MeV User Facilities of Proton Engineering Frontier Project | quadrupole, optics, survey, controls | 2376 | ||||
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The user facilities of PEFP (Proton Engineering Frontier Project) was designed. It is composed of two beamlines at the first stage and has possibility of expansion to five beamlines. One is low flux beamline for the technology developments in the fields of biological and space sciences and the other is high flux beamline for the utilization in the fields of nano and material sciences. The flux density is 1E+8~1E+10 protons/cm2-sec and 1E+10~1E+13 protons/cm2-sec each. The available energy range is 5~20MeV and the irradiation area is larger than 10cm in diameter with uniformity more than 90% for both. The specifications of these beamlines mentioned above were decided on the basis of result of user demand survey and operation experience of 45MeV proton beam test beamline installed at the MC-50 cyclotron of KIRAMS (Korea Institute of Radiological and Medical Science). The key components of these beamlines are bending magnets, magnetic quadrupole doublet or triplet, collimators, scanning magnets, target stage with water cooling system, degrader for energy control, scattering foils for flux control, etc. The beam optics was calculated using TRANSPORT and TRACE 3D simulation code.
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WEPCH190 | A Ridge Filter for 36 MeV Proton Beam Applied to BT and ST | simulation, ion, target, radioactivity | 2379 | ||||
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We designed a ridge filter to obtain a uniform depth-dose distribution as well as to deliver high linear energy transfer along the depth of a target for 36MeV proton beam. Aluminum was chosen as the material of the filter to reduce the radioactivity induced by proton irradiation. The designed ridge filter has a continuous cross-sectional line shape of ridges so that the smoothly varying depth-dose distribution can be maintained before the distal fall-off for lower proton energy than 36MeV. The height of the ridge is 6 mm, its period is also 6 mm and the minimum thickness is 0.3 mm. A Monte Carlo simulation code, MCNPX 2.5.0., was used to calculate the dose distributions. The width of the calculated uniform dose region was 11 mm for 36MeV proton beam in a water-equivalent sample.
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WEPLS001 | Secondary Particle Production and Capture for Muon Accelerator Applications | target, lattice, factory, simulation | 2394 | ||||
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Intense pulsed muon beams are required for projects such as the Neutrino Factory and Muon Collider. It is currently proposed to produce these from a high-Z target using a multi-megawatt proton driver. This paper examines the effect of proton energy on the yield and distribution of particles produced from tantalum and mercury, with further analysis using a tracking code to determine how these distributions will behave downstream, including a breakdown of loss mechanisms. Example 'muon front end' lattices are used from the UK Neutrino Factory design.
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WEPLS002 | Design and Expected Performance of the Muon Beamline for the Muon Ionisation Cooling Experiment | target, emittance, simulation, extraction | 2397 | ||||
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It is proposed to install a Muon Ionisation Cooling Experiment (MICE) at the ISIS facility, at Rutherford Appleton Laboratory (RAL). This experiment will be the first demonstration of ionisation cooling as a means to reduce the large transverse emittance of the muon beam, produced during the early stages of a Neutrino Factory. In order to permit a realistic demonstration of cooling, a beam of muons must be produced, possessing particular qualities, notably in emittance and momenta. This paper describes the current design for the muon beamline, outlining issues particular to the needs of the MICE experiment, and discusses its expected performance.
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WEPLS009 | Summary of the Low Emittance Muon Collider Workshop (February 6-10, 2006) | collider, emittance, target, luminosity | 2412 | ||||
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The Low Emittance Muon Collider workshop, held at Fermilab February 6-10, 2006 focused on the development of high-luminosity muon colliders using extreme muon beam cooling, where many constraints on muon collider designs are alleviated with beams of smaller emittance and lower intensity. The workshop covered topics related to proton drivers, targetry, muon capture, bunching, cooling, cooling demonstration experiments, bunch recombination, muon acceleration, collider lattices, interaction-point design, site boundary radiation, and detector concepts for energy frontier and Higgs particle studies. Lower emittance allows for a reduction in the required muon current for a given luminosity and also allows high energy to be attained by recirculating the beam through high frequency ILC RF cavities. The highlights of the workshop and the prospects for such colliders will be discussed.
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WEPLS011 | General Design Considerations for a High-intensity Muon Storage Ring for a Neutrino Factory | site, injection, storage-ring, target | 2418 | ||||
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Muon decay ring design, shielding, and compatibility with potential neutrino detector sites are a critical part of the International Scoping Study (ISS) for a neutrino factory. Two rings are under development: a racetrack and an isosceles-triangle ring initially for muon energy of 20 GeV, but upgradable to 50 GeV. Neutrinos from the muon decays in specially designed production straights can be directed to one or two distant detectors; the racetrack ring has one very long production straight, aligned with one detector, while the triangular ring has two straights, each half as long, aligned with two detectors. An initial site survey of accelerators and distant detectors has been made, along with the required tilt angles from the horizontal will be discussed here. (Lattice studies, injection, collimation, and RF system design are covered in a separate contribution to these proceedings.) Heating and activation effects of beam loss in the chamber walls and components will also be presented.
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WEPLS017 | International Scoping Study of a Future Accelerator Neutrino Complex | factory, target, acceleration, linac | 2427 | ||||
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The ISS, launched at NuFact05 to evaluate the physics case for a facility, along with options for the accelerator complex and detectors, is laying the foundations for a subsequent conceptual-design study. It is hosted by RAL and organized by the international community, with participants from Europe, Japan, and the U.S. Here we cover work of the Accelerator Group. For the 4 MW proton driver, we consider linacs, synchrotrons, and FFAG rings. For targets, issues of both liquid-metal and solid materials are examined. For beam conditioning (phase rotation, bunching, and ionization cooling), we evaluate schemes with and without cooling, the latter based on scaling FFAG rings. For acceleration, we examine scaling FFAGs and hybrid systems comprising linacs, dogbone RLAs, and non-scaling FFAGs. For the decay ring we consider racetrack and triangular shapes, the latter capable of simultaneously illuminating two different detectors at different baselines. Comparisons are made between various technical approaches to identify optimum design choices for the facility.
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WEPLS071 | Design Method for a Large Aperture Opposite-field Septum Magnet | septum, injection, magnet-design, vacuum | 2544 | ||||
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A novel design septum for Japan Proton Accelerator Research Center (J-PARC) delivers high intensity 3GeV proton beam to the 50GeV main ring is presented. The project requires the construction of the large aperture septum to accommodate the large size and high intensity injection beam. As there limitations due to the lattice size and restricted installation space, the septum must provide a large kick angle to the injection beam. Sufficient clearance between the circulating beam and the injection beam is also needed to reduce the beam loss to an acceptable level to avoid the serious radiation problem. To meet these challenging requirements, a large aperture, thin septum, opposite-field septum magnet has been developed. In this paper, we present the detail studies done for the optimization of the magnet, including DC and pulse magnet.
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WEPLS077 | Considerations on the Design of the Bending Magnet for Beam Extraction System of PEFP | extraction, dipole, focusing, target | 2556 | ||||
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The PEFP is designed to have two beam extraction lines at the 20 MeV end and 100MeV end for beam utilization. So, the bending magnet to extract the beam from the beam line is located among the MEBT. This implies that there is a long drift space between the focusing structures, while, from the beam dynamics study, it is recommended to make the drift space shorter. In this study, we design and compare some bending magnets to satisfy the beam dynamics requirements.
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WEPLS078 | Design Study of the 30 MeV Cyclotron Magnet | cyclotron, extraction, acceleration, injection | 2559 | ||||
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Korea Institute of RAdiological & Medical Sciences (KIRAMS) has been developing a 30 MeV cyclotron that is planned to be installed at Advanced Radiation Technology Institute, Jeongeup in late 2006. The AVF (Azimuthally Varying Field) magnet of the cyclotron was designed to produce 15-30 MeV proton beam with movable stripper foil. Four directions of extractions are available with two switching magnets. The overall shape of the magnet is cylindrical. The magnet has three kinds of holes for beam injection, vacuum pumps and RF system. The valley and hill gap ratio is about 20 for higher axial focusing. The designed magnet model and its magnetic properties of the KIRAMS-30 are presented.
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WEPLS081 | Modifications to the SPS LSS6 Septa for LHC and the SPS Septa Diluters | extraction, LHC, SPS, septum | 2565 | ||||
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The Large Hadron Collider required the modification of the existing extraction channel in the long straight section (LSS) 6 of the CERN Super Proton Synchrotron (SPS), including the suppression of the electrostatic wire septa. The newly set up fast extraction will be used to transfer protons at 450 GeV/c as well as ions via the 2.9 km long transfer line TI 2 to Ring 1 of the LHC. The girder of the existing SPS DC septa was modified to accommodate a new septum protection element. Changes were also applied to the septum diluter in the fast extraction channel in SPS LSS4, leading to the other LHC ring and the CNGS facility. The requirements and the layout of the new LSS6 extraction channel will be described including a discussion of the design and performance of the installed septum diluters.
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WEPLS119 | Power Converters for the ISIS Second Target Station Project (TS-2) | controls, septum, pulsed-power, power-supply | 2655 | ||||
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The Extract Proton Beamline to the ISIS second target station will require magnets to be powered by ac/dc power converters. A total of 50 magnets, quadrupole and dipole, require high stability dc current converters over a large dynamic range from several kW to 600kW. There is also a requirement for two 10Hz pulsed magnets to extract the proton beam from the present 50Hz target beamline, and hence specially designed power supplies are necessary. This paper describes the selection process, types of topology considerations and final selections.
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WEPLS126 | CNAO Resonance Sextupole Magnet Power Converters | controls, power-supply, sextupole, ion | 2670 | ||||
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The CNAO Resonance Sextupole Magnet Power Converter requirements for the Storage Ring of the CNAO Project are described together with performance and initial operating experience. In particular the achieved performances will be compared with the specification and the extensive modelling that was done during the design phase. Not only the tight required performances were emphasized during the design phase but also particular attention was put on reliability and minimization of the repairing time (MTTR). Some fundamental criteria, like component de-rating and standardisation, have also been taken into account during the component choice phase. All converters adopt the switching technology with full digital control and a common control interface, that, as for the other CNAO power converters, uses the same digital controller, under licence from the Diamond Light Source.
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WEPLS131 | Programmable Power Supply for Distribution Magnet for 20-MeV PEFP Proton Linac | power-supply, controls, extraction, damping | 2682 | ||||
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The distribution magnet is powered by bipolar switching-mode converter that is employed IGBT module and has controlled by a DSP (Digital Signal Process). This power supply is operated at 350A, 5 Hz programmable stair output for beam distribution to 5 beamlines of 20-MeV PEFP proton linac. Various applications for the different power supply are made simple by software. This paper describes the design and test results of the power supply.
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THPPA03 | The First CW Accelerator in USSR and a Birth of Accelerating Field Focussing | focusing, rfq, quadrupole, ion | 2755 | ||||
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In the absence of Professor Teplyakov, Robert Jameson will present the work for which Professor Teplyakov is awarded the 2006 EPS-AG Prize for Achievement. The abstract of Professor Teplyakov's presentation follows: As CW linear accelerators became required, it appeared an absolute necessity to change the initial part of the accelerator. The initial part should prepare bunches of charged particles for the further acceleration in the main part. The CW accelerator should also be economic and reliable. The problem was solved using the principles of adiabatic capture of particles and low energy injection with focusing by means of the RF field. The acceleration of bunches with non-increasing charge density was the basic idea. It allowed reduction of the injection energy without reducing the current. By 1972, initial testing in IHEP Protvino was accomplished, and the first accelerated beam was obtained in an RFQ. The URAL-30 proton linac was commissioned in 1977 in IHEP. It applies RFQ-focusing from injection up to the top energy of 30 MeV. From 1985 until the present, this facility routinely operates as an injector to a booster proton synchrotron, this feeding the entire accelerator complex of ITEP. Development of the first RFQ in the Western world was started at Los Alamos in 1978 and performed a proof-of-principle test in 1980. After that there were many articles and reports and the RFQ became widely known in the world.
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Transparencies
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THYFI01 | Tevatron Ionization Profile Monitoring | injection, electron, antiproton, IPM | 2777 | ||||
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Ionization Profile monitors have been used in almost all machines at Fermilab. However, the Tevatron presents some particular challenges with its two counter-rotating, small beams, and stringent vacuum requirements. In order to obtain adequate beam size accuracy with the small signals available, custom made electronics from particle physics experiments was employed. This provides a fast (single bunch) and dead-timeless charge integration with a sensitivity in the femto-Coulomb range, bringing the system close to the single ionization electron detection threshold. The detector itself is based on a previous Main Injector prototype, albeit with many modifications and improvements. The first detector was installed at the end of 2005, with a second detector to follow during the spring shutdown. The ultimate is to continuously monitor beam size oscillations at injection, as well as the beam size evolution during ramp and squeeze.
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Transparencies
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THPCH007 | Development of a High Current Proton Linac for FRANZ | rfq, emittance, beam-losses, bunching | 2799 | ||||
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The FRANZ Facility, a planned worldwide unique pulsed neutron source, will be built at Frankfurt University. A single RFQ or an RFQ-IH combination working at 175MHz will be used to accelerate a 200mA proton beam to the energy which can meet the demands of required neutron production. The beam dynamics study has been performed to design a flexible, short-structure and low-beam-loss RFQ accelerator. The design results and relative analyses are presented.
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THPCH025 | Electron Cloud Self-consistent Simulations for the SNS Ring | electron, SNS, simulation, lattice | 2832 | ||||
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The electron cloud dynamics is simulated for the Spallation Neutron Source ring using the self-consistent electron-cloud model for long-bunched proton beams implemented in the ORBIT code. These simulations feature simultaneous calculations of the dynamics of the proton bunch and of the electron cloud, including electron multipacting using a realistic secondary emission surface model. The frequency spectra and growth rates of the proton bunch transverse instability are studied as functions of the RF cavity voltage. The effectiveness of an electron-cloud instability suppression system is also studied using an ORBIT model of the real feedback system. SNS is a collaboration of six US National Laboratories: Argonne National Laboratory (ANL), Brookhaven National Laboratory (BNL), Thomas Jefferson National Accelerator Facility (TJNAF), Los Alamos National Laboratory (LANL), Lawrence Berkeley National Laboratory (LBNL), and Oak Ridge National Laboratory (ORNL).
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THPCH078 | Successful Bunched-Beam Stochastic Cooling in RHIC | kicker, RHIC, ion, pick-up | 2967 | ||||
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Stochastic Cooling of high energy and high frequency bunched beam has been demonstrated in RHIC at 100 GeV. Narrowing of the Schottky spectrum and shorting of the bunch length resulted from cooling the beam for 90 minutes. The purpose of the stochastic cooling is to counteract the fundamental limit of the luminosity lifetime of heavy ions in RHIC which is Intra-Beam Scattering. IBS drives transverse emittance growth and longitudinal de-bunching. The major components of the system have been tested with heavy ion and proton beams in previous runs in RHIC, demonstrating that the difficult challenges of high frequency bunched beam stochastic cooling can be overcome. The vexing problem of pollution of the Schottky spectrum by coherent components is solved with optimized filtering and high dynamic range low noise electronics. A set of 16 high-Q cavities is used to achieve adequate kicker voltage in the 5 to 8 GHz band. This technique exploits the bunched beam time structure to level the microwave power requirement and enables the use of solid state amplifiers to drive the kickers. Because RHIC did not operate with heavy ions in the FY06 run, the system was tested with specially prepared low intensity protons bunches of 2·109 particles.
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THPCH083 | A Tune Feedback System for the HERA Proton Storge Ring | coupling, quadrupole, acceleration, feedback | 2979 | ||||
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The transverse tunes of an accelerator or storage ring are important parameters which have to be controlled and adjusted continuously during beam operation in order to assure good experimental background conditions. For the HERA proton storage ring, persistent current effects of the superconducting magnets are the main source for the inadequate repeatability of the tunes without a feedback while the proton beam is accelerated. A tune feedback has been developed, implemented and tested during beam acceleration and luminosity operation. Considering the different conditions during energy ramps and luminosity runs two versions of this feedback system have been established based on different correction and peak-finding algorithms (e.g. wavelet analysis). No additional excitation is needed on top of the standard tune indication system in HERA. The tunes could be kept constant during beam accceleration with a standard deviation of delta Q = 0.003. In luminosity runs where the tune control is more critical, first tests resulted in a standard deviation which was a factor of ten smaller. The feedback system is implemented as a standard tool for beam acceleration.
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THPCH084 | Control Path of Longitudinal Multibunch-feedback System at HERA-p | controls, kicker, feedback, FIR | 2982 | ||||
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A longitudinal broadband damper system to control coupled bunch instabilities has been developed and installed in the proton accelerator HERA-p at the DESY. The control system consists of a control path and a Fast Diagnostic System (FDS) for oscillation diagnostic. The control path consists of FPGA-based digital controller, vector modulator, 1kW power amplifier, kicker-cavity and beam. In the FDS, the bunch phase signals are sampled by a digital FPGA board with 14Bit ADC (controller) with a sampling frequency of 10.4MHz. Phase calculation for all bunches and offset correction will be done by FPGA software which includes a digital filter. The filter has to be able to deal with a slowly changing synchrotron frequency. Here we consider a filter design which treats each of maximum 220 bunches as an independent oscillator which has to be damped. More sophisticated mode filter algorithms may be required to get better noise performance. The FPGA-board output signal modulates a 104 MHz sine-wave. The resulting logitudinal correction kick signal is provided by the kicker-cavity. Beside the technical details we present first operational experience and the actual system performance.
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THPCH086 | Design of a Local IP Orbit Feedback at HERA-e | electron, feedback, interaction-region, controls | 2988 | ||||
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At the electron-proton collider HERA it is often observed that the proton emittance growth rate of colliding bunches is larger compared to non-colliding proton bunches. In addition the proton background rates are increasing when the two beams are brought into collision. There are indications that a contribution comes from closed orbit oscillations of the electron beam at the two IPs. In the arcs of HERA-e oscillation amplitudes of 100-200 micrometer with frequencies of 2-15 Hz and harmonics of 50 Hz are observed. In order to stabilize the orbit at the IPs in both planes a local digital orbit feedback system with a bandwidth of more than 20 Hz has been developed. The beam position at the IPs is measured with BPMs using dedicated electronics. The four local orbit bumps are produced by air-coil steerer magnets. The data are transmitted using SEDAC field bus lines to a central PC, which is used for the computation of the correction.
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THPCH128 | Portable SDA (Sequenced Data Acquisition) with a Native XML Database | collider, controls, injection, LEFT | 3101 | ||||
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SDA is a general logging system for a repeated, complex process. It has been used as one of the main logging facility for the Tevatron Collider during Run II. It creates a time abstraction in terms understood by everyone and allows for common time tick across different subsystems. In this article we discuss a plan to re-implement this highly successful FNAL system in a more general way so it can be used elsewhere. Latest technologies, namely a native XML database and AJAX, are used in the project and discussed in the article.
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THPCH135 | 65 MEV Neutron Irradiation of ND-FE-B Permanent Magnets | radiation, electron, permanent-magnet, undulator | 3116 | ||||
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Rare-earth permanent magnets are now playing a major role in accelerator technology, from the development of beam transport systems magnets to their extensive use in synchrotron radiation sources and free electron lasers. Unfortunately, operating in a high radiation environment, rare-earth permanent magnets are subject to demagnetization caused by direct and scattered radiation. The lifetime of these components is therefore a major issue: as a result, the number of studies to clarify the demagnetization mechanism or to test materials of interest for a particular application under specific conditions of irradiation has increased in recent years. However, so far, neutron irradiation experiments have been mainly carried out with reactors, were neutrons have a wide, but mainly low, energy spectrum. We present here the results obtained at the TIARA facility of the Japan Atomic Energy Research Institute, a spalliation source of mono highly energetic neutrons. Four types of Nd-Fe-B permanent magnets (Neomax 35EH, 32AH, 27VH and 44H) representing a wide range of characteristics (remanence and coervicity) have been studied.
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THPCH155 | High-quality Proton Beam Obtained by Combination of Phase Rotation and the Irradiation of the Intense Short-pulse Laser | laser, ion, target, electron | 3158 | ||||
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Ion production from laser-induced plasma has been paid attention because of its high acceleration gradient (>100GeV/m) compared with conventional RF accelerator. Its energy spectrum is Maxwell-Boltzmann distribution with high-energy cut-off, which limited its application. The phase rotation scheme, which rotates laser produced ions by an RF electric field synchronous to the pulse laser in the longitudinal phase space, was applied to proton beam up to 0.9MeV emitted from Ti foil with 3mm thickness irradiated by focused laser-pulse with peak intensity of 9 ´ 1017W/cm2. Multi-peaks with ~6% width (FWHM) were created and intensity multiplication up to 5 was attained around 0.6MeV region. The proton production process by the intense short-pulse laser has been optimized with use of time of flight measurement of proton beam detected by a plastic scintillation counter, which is specially shielded from the heavy background of electrons and X-rays induced by the intense laser. We have succeeded in on-line measurement of such a proton signal by the detector for the first time, which played an essential role for the investigation of phase rotation scheme.
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THPCH172 | Present Status of Beam Collimation System of J-PARC RCS | radiation, synchrotron, vacuum, target | 3200 | ||||
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The precedence manufacture of the two beam collimator was carried out. In these two sets, we tested the heat transfer capacity of cooling fins and remote clamp handling system. The vertical collimator was able to keep temperature under 120 degrees C by the design heat 400W, but in case of the horizontal collimator, it went over 200 degrees C by the design heat 700W. The design was changed towards adding an air duct. About remote clamp handling system, it checked that it could attach by the He leak below 5.*10-10Pa m3/sec as a result of the helium leak examination.
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THPCH177 | Design and Construction of the PEFP Timing System for a 20 MeV Proton Beam | power-supply, extraction, controls, rfq | 3212 | ||||
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The timing system of the PEFP requires synchronization for the accelerator and for the multipurpose beam line. The system is based on an event distribution system that broadcasts the timing information globally to all the equipment. Fast I/O hardware of the timing system is to distribute appropriate timing signals to accelerator systems, including the Injector, RFQ, DTL, and user's facilities. Signals to be distributed include the synchronized pulse triggers and event information of RF system and switching magnet power supplies for the 20MeV proton beam extraction.
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THPCH192 | Experimental, Test and Research Beamlines at Fermilab | linac, target, controls, quadrupole | 3242 | ||||
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Three new external beamlines are in operation or under development at Fermilab: 1) the Main Injector Particle Production (MIPP) beamline, 2) the Mucool Test Area (MTA) beamline, and 3) a new MTEST beamline for advanced detector work for high energy experiments and the ILC. The MIPP beamline is a secondary production beamline capable of producing well-characterized beams of protons, pions, and kaons from 5-120 GeV/c using 120 GeV/c protons from the Fermilab Main Injector. The second line is a new primary 400-MeV proton beamline derived from the 400 MeV proton Linac which will provide for precision measurements of Linac beam parameters in addition to a high-intensity primary test beam for development and verification of muon ionization cooling apparatus. A dual mode operation will also provide accurate, dispersion-free measurements of the Fermilab Linac beam properties with potential for diagnostic development. Installation is planned in 2007. Finally, a third beam is also under design to provide secondary beams at ultra-low - high energies, from ~1 GeV/c to 90 GeV/c in addition to a primary 120-GeV proton mode of operation. It is anticipated that this last line will be installed in fall of 2006.
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THPCH196 | A Proof-of-Principle Experiment for a High-Power Target System | target, CERN, BNL, factory | 3254 | ||||
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The MERIT experiment, to be run at CERN in 2007, is a proof-of-principle test for a target system that converts a 4-MW proton beam into a high-intensity muon beam for either a neutrino factory complex or a muon collider. The target system is based on a free mercury jet that intercepts an intense proton beam inside a 15-T solenoidal magnetic field.
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FRXAPA01 | Neutrino Factories and Beta Beams | target, factory, CERN, acceleration | 3616 | ||||
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The presentation will review the various concepts of Neutrino Factories and Beta Beams and indicate the main challenges in terms of beam performance and technological developments. It will also present the world-wide organization to define and carry out the necessary R&D for component design, beam simulations of facility performance, and benchmarking of key subsystems via actual beam tests. Currently approved subsystem tests include the Muon Ionization Cooling Experiment (MICE), under construction at Rutherford Appleton Laboratory, and the Mercury Intense Target (MERIT) experiment, to be carried out at CERN. The major issues being examined by MICE and MERIT will be described as well as the plans and schedule to address them.
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Transparencies
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FRXBPA01 | HERA and the Next Generation of Lepton-ion Colliders | luminosity, electron, lepton, collider | 3621 | ||||
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This talk will present a summary of the physics insights gained from the lepton-hadron collider HERA and review major beam dynamics issues and lessons learned in view of LHC operation, including technical aspects related to the large number of superconducting magnets or the influence of various design choices on the overall machine performance. It will also address future plans for lepton-ion colliders, including eRHIC at BNL and the CEBAF-based ELIC, with emphasis on their luminosity reach and challenges. The talk will also mention possible high energy lepton-ion collisions, for example colliding a 1 TeV proton (or ion) beam from the Tevatron or Super-SPS with a 20-75 GeV electron beam from the ILC or CLIC (first stage).
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Transparencies
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FRYAPA01 | Developments in Proton and Light-ion Therapy | ion, synchrotron, target, linac | 3631 | ||||
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The talk will provide an overview of recent developments in hadrontherapy. It will give a background on cancer therapy with protons and ions, discussing the relative merits of protons and ions versus conventional radiotherapy. It will include status and plans for the development of hadrontherapy facilities, in particular in Europe. It will also describe the status of the Italian hadrontherapy project (CNAO).
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Transparencies
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