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| MO3002 | Overview of TEM-Class Superconducting Cavities for Proton and Ion Acceleration | linac, ion, vacuum, cryogenics | 23 | ||
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Superconducting (SC) TEM-class cavities have been developed at laboratories and institututions worldwide for cw and pulsed proton and ion linac applications. New geometries spanning nearly the full velocity range from 0.1 < v/c < 0.8 include co-axial quarter- and half-wave and single- and multi-spoke cavities. Optimized designs have large beam acceptance, high shunt impedance and good microphonics properties. Rapidly evolving and improving clean surface processing techniques have been applied to TEM cavities where achieved surface fields and rf losses are comparable to the best results presently achieved in elliptical cavity designs. Recent results for a three-spoke cavity following hydrogen degassing after fabrication show very low rf losses even at high accelerating fields and now open the possibility for substantially reduced effective cryogenic load in 2 Kelvin, rather than the historically-used 4 Kelvin, operation. At present performance levels, SC TEM-class cavities constitute the technology of choice for most ion linac applications requiring cavities up to or beyond 60 percent of the speed-of-light.
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| MOP003 | A Shared Superconducting Linac for Protons and Muons | linac, factory, target, collider | 34 | ||
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A future Fermilab proton driver* based on TESLA superconducting linac modules can provide protons to produce the muons and also accelerate the muons to be used for a neutrino factory or muon collider. Recent advances in muon cooling** imply muon emittances that are compatible with the 1300 MHz accelerating structures that are the basis for the ILC design. In the example discussed here, H- ions are accelerated to 8 GeV in the superconducting linac, then stripped, stored and bunched in a ring while the linac cavities are rephased for muon acceleration. Then the protons are extracted from the ring to produce pions and muons which are cooled in about six hundred meters, accelerated to a few GeV and injected into the linac at the point for acceleration to add 7 GeV. By recirculating the muons in the constant frequency section of such a proton driver linac, even higher energies can be achieved quickly so that losses from muon decay are minimized. By adding additional refrigeration and RF power, the repetition rate of the linac can be increased to make large increases in the average flux of a neutrino factory and the average luminosity of a muon collider.
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*G. W. Foster and J. A. MacLachlan, Proceedings of LINAC 2002, Gyeongju, Korea |
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| MOP028 | Creation of Peaks in the Energy Spectrum of Laser-Produced Ions by Phase Rotation | laser, target, ion, acceleration | 97 | ||
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Efficient acceleration of ions with use of very high electromagnetic field created by a high power laser has been paid attention because of its attainable very high acceleration gradient. Its intensity, however, has exponentially decreases according to the increase of its energy, which causes essential difficulty for its real application. For the quality improvement of laser-produced ions in their energy spreads, a scheme to apply an additional RF electric field synchronous to the pulse laser, called “Phase Rotation”,* has been applied to the ions produced from the thin foil target 3 and 5 mm, in thickness by irradiation of focused Ti:Sapphire laser with the wave length of 800 nm after optimization of the ion production process with use of real time observation of ion energy by TOF measurement.** Energy peaks with the spread of 7 % have been created in the energy spectrum at the positions depending on the relative phase between the pulse laser and the RF electric field. Possible application of “Phase Rotated” laser-produced ion beam is also to be discussed.
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* A. Noda et al., Laser Physics, Vol. 16, No.4, pp.647-653(2006). |
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| MOP039 | The SPL (II) at CERN, a Superconducting 3.5-GeV H- Linac | linac, injection, target, simulation | 127 | ||
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A revision of the physics needs and recent progress in the technology of superconducting (SC) RF cavities have triggered major changes in the design of a SC H- linac at CERN. With 4 - 5 MW beam power, the SPL can be the proton driver for a next generation ISOL-type radio-active beam facility ("EURISOL") and/or supply protons to a neutrino facility (conventional superbeam + beta-beam or neutrino factory). Furthermore the SPL can replace Linac2 and the PS booster, improving significantly the beam performance in terms of brightness, intensity, and reliability for the benefit of all proton users at CERN, including LHC and its luminosity upgrade. Compared with the first conceptual design, the beam energy is almost doubled (3.5 GeV instead of 2.2 GeV) while the length is reduced by 40%. At a repetition rate of 50 Hz, the linac re-uses decommissioned 352.2 MHz RF equipment from LEP in the low-energy part. Beyond 90 MeV the RF frequency is doubled, and from 180 MeV onwards high-gradient SC bulk-niobium cavities accelerate the beam to its final energy of 3.5 GeV. This paper presents the overall design approach, together with the technical progress since the first conceptual design in 2000.
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| MOP040 | Design of the PEFP 100-MeV Linac | linac, rfq, quadrupole, klystron | 130 | ||
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The Proton Engineering Frontier Project (PEFP) is constructing a 100 MeV proton linac in order to provide 20 MeV and 100 MeV proton beams. The linac consists of a 50 keV proton injector, a 3 MeV radio-frequency quadrupole (RFQ), a 20 MeV drift tube linac (DTL), a medium energy beam transport (MEBT), and the higher energy part (20 MeV ~ 100 MeV) of the 100 MeV DTL. The MEBT is located after the 20 MeV DTL in order to extract 20 MeV proton beams as well as to match the proton beam into the higher energy part of the linac. The 20 MeV part of the linac was completed and is now under beam test. The higher energy part of the PEFP linac was designed to operate with 8% beam duty and is now under construction. This brief report discusses the design of the PEFP 100MeV linac as well as the MEBT.
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| MOP041 | Test Results of the PEFP 20-MeV Proton Accelerator | rfq, klystron, power-supply, site | 133 | ||
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A 20 MeV proton accelerator has been developed by Proton Engineering Frontier Project (PEFP). The accelerator consists of a 50 keV proton injector, a 3 MeV radio frequency quadrupole (RFQ) and a 20 MeV DTL (Drift Tube Linac). The preliminary test is being performed at KAERI (Korea Atomic Energy Research Institute) site. A pulsed proton beam is extracted from the proton injector by switching the high voltage power supply of the ion source. The beam transmission rate through the RFQ was measured with respect to the vane voltage to set the operating point. The 20 MeV DTL consists of four tanks and the beam transmission characteristics have been checked for various parameters. In this paper, a test stand for a 20 MeV accelerator at KAERI site is introduced and the test results are discussed.
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| MOP048 | Installation of the French High-Intensity Proton Injector at Saclay | rfq, diagnostics, linac, shielding | 153 | ||
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The installation of the French high intensity injector “IPHI” is in progress on the Saclay site. The proton source, RF power system, cooling plant, diagnostics line as well as shielding are now in place. The first sections of the RFQ cavity are installed on their supports. Commissioning is planned during the first half of 2007. At the beginning of 2008, a beam chopper, developed at Cern, will be inserted between the RFQ and the diagnostics line and tested with a proton beam. At the end of 2008, part of IPHI will be moved from Saclay to Cern. New tests, intended for the LINAC4 project, will be carried out using a negative hydrogen beam. This paper describes the fabrication and assembly operations. The future of IPHI at Cern is evoked.
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| MOP050 | Construction Plans for the LENS Proton Linac | rfq, klystron, target, linac | 156 | ||
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The Low Energy Neutron Source (LENS) at Indiana University will provide moderated neutrons in the meV energy range for materials and neutron physics research as well as MeV energy range neutrons for creating a high flux neutron test environment. Neutrons will be generated by colliding 13 MeV or 21 MeV protons with a Be target. Since December 2004, we have used an existing RFQ and DTL, we have been able to deliver a 0.5% duty factor a 10 mA, 7 MeV beam to a Be target mounted next to a frozen methane moderator*. By early 2007, an additional 7 MeV to 13 MeV DTL section will be added and klystrons will be used to power the RFQ and DTL sections. This will improve the output to 3% duty factor with 20 mA at 13 MeV. A new 75 keV, 150 mA proton injector and 100 mA, high duty factor RFQ is being constructed to replace the original 3 MeV RFQ at a later date. The peak beam current available from the new injector and RFQ will increase to 50 mA with a duty factor of at least 5% or up to 100 mA with lower duty factor. In addition, a 13 MeV to 22 MeV DTL is planned to boost the maximum instantaneous flux available from the neutron source up to about 1012 n/s/cm2.
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V. P. Derenchuk, et al., "The LENS 7 MeV, 10 mA Proton Linac," PAC05, p. 3200. |
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| MOP051 | Development of an Intense Neutron Source FRANZ in Frankfurt | rfq, space-charge, ion, emittance | 159 | ||
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The Stern-Gerlach-Center recently founded at the University of Frankfurt gives the possibility for experiments in accelerator physic, astrophysic and material sience research. It is planned to develop an intense neutron generator within the next 4 years. The proton driver linac consists of a high voltage terminal already under construction to provide primary proton beam energies of max. 150 keV. A volume type ion source will deliver a DC beam current of 100-250 mA at a proton fraction of 90%. A low energy beam transport using two solenoids will inject the proton beam into an RFQ while a chopper at the entrance of the RFQ will create a pulse length of 50 ns and a repetition rate up to 250 kHz. A drift tube cavity for the variation of the beam energy in a range of 1.9 – 2.4 MeV will be installed downstream of the RFQ. Finally a bunch compressor of the Mobley type forms a proton pulse length of 1 ns at the Li target. The maximum energies of the neutrons being adjustable between 100 keV and 500 keV by the primary proton beam. The detailed concept of the high current injector, numerical simulation of beam transport and losses will be presented together with first experimental results.
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| MOP052 | First Performance Test of an Integrated RFQ-Drifttube-Combination | rfq, ion, simulation, bunching | 162 | ||
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In the frame of a collaboration with the GSI in Darmstadt an RFQ-Drifttube-Combination for the Heidelberg cancer therapy center HICAT has been designed, built and successfully beam tested at the IAP Frankfurt. The integration and combination of both an RFQ and a rebunching drifttube unit inside a common cavity forming one single resonant RF-structure has been realized for the first time with this machine. The results of the beam measurements and questions about the beam dynamics simulations have been investigated in detail with the code RFQSIM.
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| MOP057 | A Fault Recovery System for the SNS Superconducting Cavity Linac | SNS, linac, klystron, beam-loading | 174 | ||
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One of the advantages for the change of the Spallation Neutron Source (SNS) linac from copper to superconducting cavities, was the possibility of fault tolerance. Namely, the ability to rapidly recover from a cavity failure, retune the downstream cavities with minimal user disruption. While this is straightforward for electron machines, where beta is constant, it is more involved for the case of proton machines, where the beta changes appreciably throughout the Superconducting Linac (SCL). For SNS when the SCL is first turned on, each cavity’s RF amplitude and phase (relative to the beam) are determined with a beam based technique. Using this information a model calculated map of arrival time and phase setpoint for each cavity is constructed. In the case of cavity failure(s) the change in arrival time at downstream cavities can be calculated and the RF phases adjusted accordingly. Typical phase adjustments are in the 100 – 1000 degree range. This system has been tested on the SNS SCL in both controlled tests and a need based instance in which more than 10 cavity amplitudes were simultaneously reduced. This scheme and results will be discussed.
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| MOP061 | The 70-MeV Proton Linac for the Facility for Antiproton and Ion Research FAIR | linac, rfq, emittance, simulation | 186 | ||
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A significant part of the experimental program at FAIR is dedicated to antiproton (pbar) physics requiring up to 7·1010 cooled pbars per hour. Taking into account the pbar production and cooling rate, this is equivalent to a primary proton beam of 2·1016 protons per hour to be provided by a 70 MeV proton linac preceding two synchrotrons. It has to deliver a pulsed proton beam of 70 mA of 36 μs duration at a repetition rate of 4 Hz. The normalized transverse emittances must not exceed 2.8 mm mrad and the total relative momentum spread must be less than 0.1%. The normal conducting DTL comprises 12 Crossed-bar H-cavities (CH) fed by six rf-power sources in total. The basic layout of the linac as well as the overall cost estimate has been completed including several reviews by external committees. A technical report has been completed in May 2006. This paper gives a general overview on the status of the project.
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| TU3001 | High-Current Proton Beam Investigations at the SILHI-LEBT at CEA/Saclay | emittance, ion, space-charge, ion-source | 232 | ||
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For the injection of a high current proton beam into the future proton LINAC at GSI for FAIR the ion source and the low energy beam transport system have to deliver a 100 mA proton beam with an energy of 95 keV within an acceptance of 0.3 mm mrad (normalized, rms) at the entrance of the RFQ. Besides the ion source a 2-solenoid focusing system is foreseen as an injection scheme for the subsequent RFQ. The beam parameters of the SILHI ion source and the 2-solenoid LEBT setup generally meet these requirements. Therefore joint emittance measurements on various beam parameters have been performed at the end of the LEBT system. In the frame work of the design study for the future proton LINAC it was a unique possibility to investigate the injection of a high current proton beam into a low energy beam transport system under the influence of space charge. The measurements reveal that a proton current of 100 mA can be achieved at the end of the LEBT while the emittance (95 %, rms, normalized) is as high as 0.3 to 0.5 mm mrad.
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| TUP010 | The Beam Halo Monitor of SARAF | target, background, vacuum, scattering | 265 | ||
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A main requirement for the SARAF accelerator is ‘hands-on’ maintenance, which implies a maximum beam loss of 1 nA per meter. In Phase I of SARAF (4-5 MeV ions at full current), we need to map the beam halo (BH) down to below 1 nA in order to predict, using beam dynamics calculations, the beam loss in the full accelerator. Mapping the halo of a 4 MeV, 2 mA ion beam down to below 1 nA is unprecedented, so we developed a BH monitor, which incorporates a direct charge measurement and several nuclear techniques, including Rutherford scattering 197Au(p,p)197Au, 7Li(p,n)7Be leading to both neutrons and the radio-isotope 7Be (measured offline post irradiation) and 19F(p,alpha)16O leading to high energy gamma rays. The current is derived using published cross sections. In this paper, we present the SARAF Phase I BH monitor and describe the various measurement techniques. In addition, results of feasibility studies at the Pelletron accelerator of the Weizmann Institute are given. The results of the various current measurement techniques are consistent with the standard Pelletron Faraday Cup to better than 20%. This is sufficient for mapping the SARAF beam halo to the desired accuracy.
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| TUP021 | Wire Profile Monitors in J-PARC Linac | electron, linac, simulation, rfq | 293 | ||
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We plan to install wire scanners for J-PARC linac in order to measure beam profile and emittance. They have been designed to capture electrons in H-, 7um-diameter carbon wires are used in 3MeV point and 30um-diameter tungsten wires are used for 50-181MeV point. We plan to set 36 wire scanners in linac and beam dumps. In this paper, we report the result of beam test with 3MeV beam at KEK and the calculation about signal and wire temperature.
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| TUP034 | Development of a Superconducting RF Module for Acceleration of Protons and Deuterons at Very Low Energy | vacuum, alignment, linac, acceleration | 321 | ||
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A prototype superconducting accelerating module housing six 176 MHz half wave resonators and three superconducting solenoids is currently under production at Accel as part of a 40 MeV linear accelerator at the Soreq NRC. The module will accelerate protons and deuterons from energy of 1.5 MeV/u up to 6.5 MeV. The design is based on a peak electric field gradient of 25 MV/m and maximum 10 W of power dissipation in the helium bath by each cavity. Main design considerations of the cavities, solenoids, tuners and couplers as well as for the module especially in view of assembly and alignment will be presented. First cold cavity test results obtained in Accel’s new cold RF test facility will be presented. Prototypes of the tuner, helium vessel, solenoids and the couplers are under construction and partly under test.
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| TUP074 | Beam Dynamics Simulations of SARAF Accelerator including Error Propagation and Implications for the EURISOL Driver | linac, simulation, lattice, rfq | 426 | ||
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Beam dynamics simulations of the SARAF (Soreq Applied Research Accelerator) superconducting RF linear accelerator have bean performed in order to establish the linear accelerator design. The multi-particle simulation includes 3D realistic electromagnetic field distributions, space charge forces and fabrication, misalignment and operation errors. A 4 mA deuteron beam is accelerated up to 40 MeV with a moderated rms emittance growth and a high real-estate acceleration gradient of 2 MeV/m. An envelope of 40,000 macro-particles is kept under a radius of 11 mm, well below the beam pipe bore radius. The accelerator design for SARAF is proposed as an injector for the EURISOL driver accelerator. The basic Accel 176 MHz β0=0.09 and β0=0.15 HWR lattice was extended to 90 MeV based on the LNL 352 MHz β0=0.31 HWR. The matching between both lattices ensures smooth transition and the possibility to extend the accelerator to the required EURISOL ion energy.
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| TUP088 | Benchmarking of Simulation Codes TRACK and ASTRA for the FNAL High-Intensity Proton Source | simulation, space-charge, emittance, rfq | 466 | ||
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The FNAL High Intensity Proton Source is an 8-GeV superconducting H-minus Linac conceived with the primary mission of enabling 2 MW beam power from the Main Injector at 120 GeV for the Fermilab neutrino program. The main tool used for the design of this accelerator is the beam dynamics code TRACK developed by Argonne National Laboratory to fulfill the requirements of proton and heavy-ion linacs. ASTRA, developed by DESY (Hamburg, Germany) and mainly used for the design of electron photo-injectors, also offers the possibility to simulate acceleration of hydrogen ions. Benchmarking of TRACK and ASTRA is presented in this paper for a zero current and a 30 mA beam from the exit of the RFQ (2.5 MeV) to the end of the accelerating section (8 GeV).
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| TUP089 | Computer Simulations of a High-Current Proton Beam at the SILHI-LEBT | ion, emittance, simulation, space-charge | 469 | ||
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For the injection of a proton beam into the future proton LINAC for FAIR the ion source and the low energy beam transport system have to deliver a 100 mA proton beam with an energy of 95 keV at the entrance of the RFQ within an acceptance of 0.3 π mm mrad (normalized, rms). A 2-solenoid focusing system is foreseen as an injection scheme. The beam parameters of the SILHI ion source and the 2-solenoid LEBT setup at CEA/Saclay fulfill these requirements. Therefore joint emittance measurements on various beam parameters have been performed at the end of 2005. This article presents the computer simulations of the ion source extraction and LEBT, which supplemented these measurements using the KOBRA3-INP computer code in order to study the influence of space charge effects. These simulations have been performed for various solenoid settings and for different space charge compensation degrees clearly revealing that the ion beam transport within the LEBT is influenced by space charge forces.
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| TUP090 | Advances of NPK LUTS Contraband Detection System | rfq, linac, acceleration, radiation | 472 | ||
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Principle and project of NPK LUTS contraband detection technological complex (CDTC) was presented by authors at EPAC 2002. This paper reviews researches connected with 433 MHz ion linacs creation for the last four years. Main part is description of designing and testing of RFQ and APF resonators. State of affairs of other CDTC system is described briefly.
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| TUP091 | Choice of Ion Linac as Neutron Generator for Contraband-Detection System | linac, target, rfq, background | 475 | ||
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8 Mev proton linac and 4 Mev deuteron linac with working frequency 433 MHz are considered as neutron generator for detection system of explosive and fission. Required beam parameters, target materials, pulsed modulation and detection methods are discussed. Possible schemes of accelerating system of contraband detection complex are proposed. One supposes using of RFQ for deuteron linac and RFQ with IH cavity as proton one. Choice is determined by some few criterions: cost, sizes, safety, hardness of manufacturing and tuning.
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| WE2004 | 100 MeV High-Duty-Factor Proton Linac Development at KAERI | klystron, rfq, linac, power-supply | 501 | ||
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The Proton Engineering Frontier Project (PEFP) is developing a 100 MeV high-duty-factor proton linac, which consists of a 50 keV proton injector, a 3 MeV radio frequency quadrupole, a 20 MeV drift tube linac, a 20 MeV beam transport line, a 100 MeV drift tube linac, and a 100 MeV beam transport line. It will supply proton beams of 20 MeV and 100 MeV to users for proton beam applications with the beam duty factor of 24% and 8% respectively. The 20 MeV front-end accelerator with CW RF systems had been constructed at KAERI test stand, and the rest part of the accelerator is being fabricated and will be installed in the new site at Gyeongju City. The preliminary results of the 20 MeV proton linac and the status of the 100 MeV proton linac will be presented.
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| TH1004 | A 70-MeV Proton Linac for the FAIR Facility Based on CH - Cavities | linac, coupling, rfq, quadrupole | 526 | ||
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Future Accelerators for fundamental and for applied research will need a significant improvement in injector capabilities. This paper will describe the concept and the status of the 70 MeV, 70 mA proton injector for GSI - FAIR and compare the CH - linac design with traditional DTL concepts. Improvements in the space charge routine of the LORASR code as well as CH - prototype cavity development and cavity grouping with respect to commercial 3 MW rf power amplifiers is reported. Additionally, the potential of robust superconducting low and medium energy high current linac sections will be explained on the basis of experimental results from a first 19 cell s.c. 350 MHz CH - prototype cavity.
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| THP018 | Design Progress of the Re-bunching RF Cavities and Hybrid Quadrupoles for the RAL Front-End Test Stand (FETS) | quadrupole, linac, impedance, simulation | 604 | ||
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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. Two candidate re-bunching RF cavity designs are considered: the space efficient Drift Tube Linac type (DTL) with integrated quadrupoles, and the high shunt impedance Coupled Cavity Linac type (CCL) with external quadrupoles. Preliminary RF simulations in 2D and 3D are presented, and a comparison, emphasising the advantages and disadvantages of each design is made. 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. The suitability of the compact hybrid quadrupole for implementation in the low energy Drift Tube Linac (DTL) is suggested and discussed.
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| THP041 | 400-kW RF Amplifier for a 201.5-MHz Deuteron RFQ Accelerator | rfq, linac, power-supply, klystron | 670 | ||
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The dedicated 400kW RF amplifier with hypervaportron TH781 tetrode for a 201.5MHz Deuteron RFQ accelerator has been manufactured and tested successfully. It can deliver 400kW pulse power over RF frequency range from 199MHz to 203MHz with maximum pulse duration of 1ms and 10% duty cycle. The exciter with solid state transistors can output 1kW at both CW and pulse modes. The driver stage can output maximum 20kW. The dummy load with CW 50kW and peak to average ratio of 10 has been modified to fit the requirements of amplifier test measurements.
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| THP049 | LANSCE DTL Longitudinal Field Measurements at High Power | insertion, resonance, linac, acceleration | 691 | ||
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Shifts in proton beam tuning were observed in the DTL portion of the Los Alamos Neutron Science Center (LANSCE) Accelerator corresponding with cooling system obstructions during the 2003 operational cycle. A diagnostic system was developed to measure longitudinal field changes at the operational field levels to confirm the source of the tune shifts and track the effectiveness of cooling system repairs. This paper describes the diagnostic system and the results of field distribution measurements at high RF power in the accelerating structures.
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| THP054 | Spoke Cavity Developments for the EURISOL Driver | vacuum, cryogenics, linac, diagnostics | 704 | ||
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EURISOL is the next generation of Radioactive Ion Beam (RIB) facility which aims at the provision of high intensity beams of radioactive nuclei with variable energy, from a few keV to greater than 100 MeV per nucleon, at an intensity several orders of magnitude higher than those currently available. The driver of EURISOL has to accelerate protons at a final energy of 1 GeV and 5 mA current, but also deuterons at 200 MeV (total energy). For the intermediate energy part of the driver, a solution based on superconducting (SC) spoke cavities is under study at the IPN Orsay laboratory. In this paper are presented the results of beam dynamics simulations for the linac, experimental results on the β = 0.15 spoke cavity, as well as achievements on the power coupler and cold tuning system. A new horizontal cryostat for performing a test of a fully equipped spoke cavity is detailed and an optimized design for a new β ~0.35 spoke prototype is also presented.
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| THP056 | Design of 325-MHz Single and Triple Spoke Resonators at FNAL | linac, vacuum, pulsed-power, target | 707 | ||
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We present the design of two 325 MHz superconducting single spoke resonators at β=0.22 and β=0.4 and a 325 MHz superconducting triple spoke resonator at β=0.62 for the front end of a 2 MW proton linac. We describe the optimization of the spoke resonator electromagnetic performance and how the resonator structural integrity and shape is ensured. We describe the mechanical design of the slow tuner mechanism and, via a coupled ANSYS-MWS analysis, how the mechanism adjusts the resonator operating frequency. The RF design of the power coupler is also presented
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| THP068 | RF Characteristics of the SDTL for the J-PARC | linac, insertion, synchrotron, target | 740 | ||
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For the J-PARC linac, a Separated type DTL (SDTL) is used to accelerate an H- ion beam from 50MeV to 191MeV. The SDTL consists of 32 tanks and the operating frequency is 324MHz. It has 4 drift tubes and 2 half tubes (5cells), 2 fix tuners, 1 movable tuner and 1 RF input coupler. The inner diameter is 520mm and the length is approximately from 1.5m (SDTL1) to 2.5m (SDTL32). The focusing magnets are set between the tanks. We have measured the RF characteristics of the SDTL tanks and adjusted the field distribution since last summer. The measured Q value was above 90% of ideal SUPERFIS value, the field distribution was adjusted within ±1% for all the tanks. In this paper, the results of RF measurements of the SDTL tanks are described.
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| THP069 | DTL and SDTL Installation for the J-PARC | alignment, linac, quadrupole, synchrotron | 743 | ||
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Three DTL tanks and 30 SDTL tanks have been installed precisely in the under-ground tunnel of the J-PARC project. The alignment of the tank was mainly done by using an alignment telescope. The distance of the center axis of the tank from the beam axis was measured by the telescope of which axis is in the beam line. The distance is minimized by adjusting the position of the tank on the stand. The beam axis in the tank is defined by the two optical target which are put on the template fixed on both ends of the tank cylinder for the DTL. After the installation of the tanks the movable tuners and the input couplers were also fixed on the tank. In the paper the measured tank position will be described in detail.
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| THP076 | Prototyping of a Superconducting Elliptical Cavity for a Proton Linac | linac, SNS, vacuum, radiation | 758 | ||
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A superconducting cavity has been designed for acceleration of particles travelling at 81% the speed of light (β = 0.81). Possible applications include the proposed Fermilab Proton Driver Linac. The cell shape is similar to the β = 0.81 cavity for the Spallation Neutron Source Linac, but the resonant frequency is 1.3 GHz rather than 805 MHz and the beam tube diameter matches that of the 1.3 GHz cavity for the TeSLA Test Facility. Six single-cell prototypes are being fabricated and tested. Three of these cavities are being formed from standard high purity fine grain niobium sheet. The rest are being fabricated from large grain niobium, following up on the work at Jefferson Lab to investigate the potential of large grain material for cost savings and/or improved RF performance. The fabrication of two 7-cell cavity prototypes (one fine grain, one large grain) is planned. A status report on this prototyping effort will be presented.
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| THP084 | Design of an 8-Gev H- Transport and Multiturn Injection System | injection, linac, lattice, dipole | 779 | ||
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The baseline design of the transport and multiturn injection of 8 GeV H- to the FNAL Main Injector from a proposed 8 GeV superconducting linac will be discussed.
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| THP089 | Testbench of the HICAT RFQ at GSI | rfq, ion, linac, RF-structure | 791 | ||
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In April 2006 the commissioning of the ion linac for the HICAT therapy facility in Heidelberg, Germany was started. In preparation of this commissioning process beam tests of the RFQ cavity with protons were carried out at GSI. The RFQ cavity for the HICAT facility was delivered to GSI in March 2005. The operation with an rf power up to 200 kW and a pulse width of 500 μsec could be accomplished successfully after a short time of rf-conditioning to assure the operation mode with carbon ions. A testbench for the RFQ cavity was constructed at GSI to allow for exact measurements of the output energy with the time of flight (ToF) method in addition to the beam tests at IAP Frankfurt. Due to the fact that the rebuncher is fully integrated into the RFQ rf-structure beam studies with different mechanical settings of the rebuncher had to be conducted. For each setting the effective voltage of the rebuncher could be estimated. The final mechanical setting was chosen with respect to required longitudinal matching to the IH structure behind of the RFQ.
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| FR2001 | Targets and Ion Sources Development at ISAC-TRIUMF | target, ion, ion-source, laser | 823 | ||
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The ISAC facility is operational since 1998, we utilize the proton beam from the TRIUMF H- cyclotron to produce the radioactive ion beams (RIB) via the isotopic separation on line (ISOL) method. The ISAC facility is designed to accommodate 100 μA proton beam at 500 MeV. Since beginning operation irradiation currents have progressively increased from initial values of ~ 1 μA to present levels of up to 75 μA on refractory metal foil targets and recently equally on composite carbide targets. Beyond the 50 μA limit the target has to be cooled. A new target equipped with fins has been developed that can sustain proton beam up to 100 μA. The RIB intensities depend not only on the target but also on the ability to produce ion beam. The ion sources design for on-line applications are extremely important because of the close contact with the target. They must sustain high radiation field and operate in a large gas pressure range. In order to produce a larger range of beam we are looking at other types, ECR, FEBIAD, negative and the laser ion sources. Report on the recent progress accomplished during the past years will be made.
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