Keyword: rfq
Paper Title Other Keywords Page
MOPPC072 Mathematical Model of Charged Particles Dynamics Optimization in RFQ Accelerators emittance, controls, resonance, focusing 298
 
  • A.D. Ovsyannikov
    St. Petersburg State University, St. Petersburg, Russia
  
  Mathematical model of optimization of transverse motion of charged particles in accelerators is suggested. Linear and nonlinear systems are considered when describing the transverse motion. Interaction of the particles is taken into account. Optimization algorithm based on minimax functionals is built. Numerical results for RFQ accelerators are presented.  
 
MOPPC082 Beam Dynamics Simulations inProject X RFQ with CST Studio Suite simulation, acceleration, linac, quadrupole 328
 
  • G.V. Romanov
    Fermilab, Batavia, USA
  
  Typically the RFQs are designed using the Parmteq, DesRFQ and other similar specialized codes, which produces the files containing the field and geometrical parameters for every cell. The beam dynamic simulations with these analytical fields are, of course, ideal realizations of the designed RFQs. The new advanced computing capabilities made it possible to simulate beam and even dark current in the realistic 3D electromagnetic fields in the RFQs that may reflect cavity tuning, presence of tuners and couplers, RFQ segmentation etc. The paper describes the utilization of full 3D field distribution obtained with CST Studio Suite for beam dynamic simulations using both PIC solver of CST Particle Studio and the beam dynamic code TRACK.  
 
MOPPC091 Parallel 3D Simulations to Support Commissioning of a Solenoid-based LEBT Test Stand simulation, solenoid, emittance, cyclotron 349
 
  • B.T. Schwartz, D.T. Abell, D.L. Bruhwiler, Y. Choi, S. Mahalingam, P. Stoltz, J. von Stecher
    Tech-X, Boulder, Colorado, USA
  • B. Han, M.P. Stockli
    ORNL, Oak Ridge, Tennessee, USA
  
  Funding: This work is supported by the US DOE Office of Science, Office of Basic Energy Sciences, including grant No. DE-SC0000844.
A solenoid-based low-energy beam transport (LEBT) test stand is under development for the Spallation Neutron Source (SNS). To support commissioning of the test stand, the parallel Vorpal framework is being used for 3D electrostatic particle-in-cell (PIC) simulations of H− beam dynamics in the LEBT, including impact ionization physics and MHz chopping of the partially-neutralized \Hm beam. Here we describe the process of creating a partially-neutralized beam and examine the effects of a single chopping event on the beam's emittance. 		 
 
MOPPD037 Investigation of Space Charge Compensation at FETS space-charge, ion, emittance, ion-source 445
 
  • J.K. Pozimski, S.M.H. Alsari, P. Savage
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  • D.C. Faircloth, A.P. Letchford
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  
  In order to contribute to the development of high power proton accelerators in the MW range, to prepare the way for an ISIS upgrade and to contribute to the UK design effort on neutrino factories, a front end test stand (FETS) is being constructed at the Rutherford Appleton Laboratory (RAL) in the UK. The aim of the FETS is to demonstrate the production of a 60 mA, 2 ms, 50 pps chopped beam at 3 MeV with sufficient beam quality. The ion source and LEBT are operational with the RFQ under manufacture. In the LEBT a high degree of space charge compensation (~90%) and a rise time of space charge compensation around ~ 50 μs could be concluded indirectly from measurements . As a more detailed knowledge is of interest also for other projects like ESS the FETS LEBT was updated to perform a detailed experimental analysis of space charge compensation. In this paper the results of the experimental work will be presented together with discussion of the findings in respect to beam transport.  
 
MOPPR056 Experimental and Theoretical Studies of a Low Energy H− beam acceleration, ion-source, solenoid, ion 912
 
  • C. Gabor
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • G.E. Boorman
    Royal Holloway, University of London, Surrey, United Kingdom
  • A.P. Letchford
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  
  The Front End Test Stand (FETS) at the Rutherford Appleton Laboratory (RAL) is intended to demonstrate the early stages of acceleration (0-3 MeV) and beam chopping required for high power proton accelerators. At the moment, the RFQ is under construction and there is a need to understand the matching of the Low Energy Beam Transport (LEBT) into the RFQ as conclusive as possible. The parameter of interest may include solenoid settings, steering effects but also the influence of the post acceleration of the ion source and potential effects of space charge compensation. Two emittance scanner are installed and can be combined with scintillator acting as a beam profile monitor and auxiliaries like current measurement.  
 
MOPPR072 Fermilab PXIE Beam Diagnostics Development and Testing at the HINS Beam Facility diagnostics, laser, linac, emittance 954
 
  • V.E. Scarpine, B.M. Hanna, V.A. Lebedev, L.R. Prost, A.V. Shemyakin, J. Steimel, M. Wendt
    Fermilab, Batavia, USA
  
  Funding: This work was supported by the U.S. Department of Energy under contract No. DE-AC02-07CH11359.
Fermilab is planning the construction of a prototype front end of the Project X linac. The Project X Injector Experiment (PXIE) is expected to accelerate 1 mA cw H− beam up to 30 MeV. Some of the major goals of the project are to test a cw RFQ and H− source, a broadband bunch-by-bunch beam chopper and a low-energy superconducting linac. The successful characterization and operation of such an accelerator places stringent requirements on beam line diagnostics. These crucial beam measurements include bunch currents, beam orbit, beam phase, bunch length, transverse profile and emittance, beam halo and tails, as well as the extinction performance of the broadband chopper. This paper presents PXIE beam measurement requirements and instrumentation development plans. Also presented are plans to test many of these instruments at the Fermilab High Intensity Neutrino Source (HINS) beam facility. Since HINS is already an operational accelerator, utilizing HINS for instrumentation testing allows for quicker development of the required PXIE diagnostics. 		 
 
TUPPD023 RFQ LINAC Commissioning and Carbon4+ Acceleration for Ag15+ Acceleration via Direct Plasma Injection Scheme ion, plasma, laser, linac 1458
 
  • T. Yamamoto, M. Washio
    RISE, Tokyo, Japan
  • K. Kondo, M. Okamura, M. Sekine
    BNL, Upton, Long Island, New York, USA
  
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
High intensity, high charge state, various ion species and small emittance heavy ion beam is required for particle physics, medical uses, inertial fusion, and a simulator of space radiation. Direct Plasma Injection Scheme (DPIS), the way to make laser abrasion plasma developed in the past several years, is used for Heavy Ion beam Accerelation. High density plasma with an initial drift velocity will fly to the entrance of the Radio Frequency Quadropole (RFQ) LINAC; ions will be separated from plasma via high voltage and injected it to RFQ LINAC directly. After RFQ LINAC, ions accepted to the RF buckets are accelerated to a current of over 10mA. Until now, we tried a carbon target using the partial modulation rod of the RFQ LINAC, and succeeded in accelerating carbon4+, carbon5+, and carbon6+ non-bunched beam.* In this instance, we succeeded in commissioning of new full modulation RFQ rod designed for the charge mass ratio(q/A) 1/6. We tested the acceleration of carbon4+, and it could be catched by the RF bucket and accelerated. After this, we'll try accelerating carbon2+ (q/A=1/6) for demonstrating the feasibility of the Ag15+ ion accelerating.
* T. Kanesue, M. Okamura, K. Kondo, J. Tamura, H. Kashiwagi, Z. Zhang, Drift distance survey in direct plasma injection scheme for high current beam production, Rev Sci Instrum. 2010 Feb;81(2):02B723 		 
 
TUPPD026 Study of the RFQ Beam Cooler for SPES project ion, quadrupole, emittance, extraction 1467
 
  • M.M. Maggiore, A.M. Porcellato, S. Stark
    INFN/LNL, Legnaro (PD), Italy
  
  The SPES project is the new Radioactive Ion Beam facility under construction at Laboratori Nazionali of Legnaro, Italy. In this framework in order to improve the beam quality in terms of emittance and energy spread, a study of a new RFQ beam cooler device is accomplishing. The electromagnetic design of the RFQ section and the electrostatic layout of the injection and extraction regions have been done. The study about the beam dynamic is going on by means of dedicated codes which allow to take into account the interaction of the ions with the buffer gas needed to cool the beams. The status of the project and the results will be shown in this report.  
 
TUPPD047 Injection Sequence for High-power Isochronous Cyclotrons for ADS Fission cyclotron, ion, ion-source, emittance 1509
 
  • S. Assadi, K.E. Badgley, C. Collins, J. Comeaux, R. Garrison, P.M. McIntyre, A. Sattarov
    Texas A&M University, College Station, Texas, USA
  
  Funding: This work is supported by grants from the State of Texas (ASE) and the Mitchell Family Foundation.
A high-current injector sequence is being developed for use in a flux-coupled stack of high-current cyclotrons for accelerator-driven subcritical (ADS) fission. The design includes an ECR ion source, LEBT, RF quadrupole, and multi-stage chopper. A first cyclotron then accelerates the beams to 100 MeV for injection to the sector isochronous cyclotron. Provisions for control of emittance and bunch tails are described. 		 
 
WEPPR019 Catalogue of Losses for the IFMIF Prototype Accelerator linac, SRF, solenoid, quadrupole 2982
 
  • P.A.P. Nghiem, N. Chauvin, D. Uriot
    CEA/DSM/IRFU, France
  • M. Comunian
    INFN/LNL, Legnaro (PD), Italy
  • C. Oliver
    CIEMAT, Madrid, Spain
  
  For machine and personal protection purposes, precise knowledge of beam loss location and power are crucial, especially in a high intensity, high power accelerator like the IFMIF prototype. This paper aims at discussing the protocol of appropriate studies in order to give the catalogue of beam losses in different conditions: nominal, tuning and accidental. Then results of these studies are given.  
 
WEPPR027 Complete Electromagnetic Design of the ESS-Bilbao RFQ Cold Model quadrupole, dipole, simulation, radio-frequency 2991
 
  • A. Vélez, I. Bustinduy, J. Feuchtwanger, N. Garmendia, O. González, I. Madariaga, J.L. Muñoz, D. de Cos
    ESS Bilbao, Bilbao, Spain
  • F.J. Bermejo
    Bilbao, Faculty of Science and Technology, Bilbao, Spain
  • V. Etxebarria, J. Portilla
    University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
  
  In this work, the ESS-Bilbao 352,2 Mhz RFQ Cold Model to be built in the ESS-Bilbao accelerator facility is presented. The Cold Model intends to be a small scale representation of the final 4 meters long RFQ which will be able to accelerate a 75 mA proton beam from 75 keV to 3 MeV. The work shown here covers the complete electromagnetic design process of the Cold Model which will be built in aluminium with a total length of 1 meter. Moreover, in order to find out fabrication tolerances, a longitudinal test modulation in the vane regions similar to the one designed for the final RFQ is included in the Cold Model. This modulation represents also a useful tool in order to test the agreement between measurements and electromagnetic simulations. In addition, a complete parametric study of the RFQ ends and radial matchers is presented as an important design parameter able to adjust the field flatness. Finally, slug tuning rods are also added to be able to test the tuning procedures. A final RFQ Cold Model prototype has been designed and is currently under fabrication.  
 
THEPPB001 Design and Fabrication of The ESS-Bilbao RFQ Prototype Models vacuum, laser, alignment, simulation 3228
 
  • I. Bustinduy, F.J. Bermejo, J. Feuchtwanger, N. Garmendia, A. Ghiglino, O. González, P.J. González, I. Madariaga, J.L. Muñoz, I. Rueda, F. Sordo Balbin, A. Vélez, D. de Cos
    ESS Bilbao, Bilbao, Spain
  • V. Etxebarria, J. Portilla
    University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
  • A. Garbayo
    AVS, Eibar, Gipuzkoa, Spain
  • S. Jolly
    UCL, London, United Kingdom
  • S.R. Lawrie, A.P. Letchford
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • J.K. Pozimski, P. Savage
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  
  As part of the development of the ESS-Bilbao Accelerator in Spain, two different sets of radio frequency quadrupole (RFQ) models have been developed. On one hand, a set of four oxygen free high conductivity copper weld test models has been designed and manufactured, in order to test different welding methods as well as other mechanical aspects involved in the fabrication of the RFQ. On the other hand, a 352.2 MHz four vane RFQ cold model, with a length of 1 meter, has been designed and built in Aluminum. It serves as a good test bench to investigate the validity of different finite element analysis (FEA) software packages. This is a critical part, since the design of the final RFQ will be based on such simulations. The cold model also includes 16 slug tuners and 8 couplers/pick-up ports, which will allow to use the bead-pull perturbation method, by measuring the electric field profile, Q-value and resonant modes. In order to investigate fabrication tolerances, the cold model also comprises a longitudinal test modulation in the vanes, which is similar to the one designed for the final RFQ.  
 
THPPC007 Coupling Cavity Design of RF Input Coupler Tests for the IFMIF/EVEDA Prototype RFQ Linac coupling, cavity, linac, beam-transport 3284
 
  • S. Maebara
    JAEA, Ibaraki-ken, Japan
  • M. Ichikawa
    Japan Atomic Energy Agency (JAEA), International Fusion Energy Research Center (IFERC), Rokkasho, Kamikita, Aomori, Japan
  
  In the design of prototype RFQ linac for the IFMIF/EVEDA Project, a 175MHz RFQ, which has a longitudinal length of 9.78m, was proposed to accelerate deuteron beam up to 5MeV. The operation frequency of 175MHz was selected to accelerate a large current of 125mA in cw mode. The overall driving RF power of 1.28 MW by 8 RF input couplers has to be injected to the RFQ cavity. For the transmitted RF power tests of RF couplers, a coupling cavity to connect with two RF couplers is needed. For this purpose, two types of coupling cavities for the 175MHz have been designed. One is a capacitive coupling cavity with a co-axial waveguide and double loop coupling structures, and the other one is a ridge cavity type with a rectangular waveguide. In this article, these RF designs and engineering designs will be presented in detail.  
 
THPPC008 Coupling Factor Evaluation of the RF Input Coupler for the IFMIF/EVEDA RFQ Linac coupling, beam-loading, linac, cavity 3287
 
  • S. Maebara
    JAEA, Ibaraki-ken, Japan
  • M. Ichikawa
    Japan Atomic Energy Agency (JAEA), International Fusion Energy Research Center (IFERC), Rokkasho, Kamikita, Aomori, Japan
  • A. Palmieri
    INFN/LNL, Legnaro (PD), Italy
  
  In the design of prototype RFQ linac for the IFMIF/EVEDA Project, a 175 MHz RFQ, which has a longitudinal length of 9.78m, was proposed to accelerate deuteron beam up to 5MeV. The operation frequency of 175MHz was selected to accelerate a large current of 125mA in CW mode. The overall driving RF power of 1.28 MW by 8 RF input couplers has to be injected to the RFQ cavity. As a part of the validation of the coupler design, the beta factor (coupling coefficient) was measured on Aluminum RFQ at INFN Legnaro with on-purpose, real-scale dummy aluminum couplers for the installed depths of L=27, 40, 45, 48 and 73 mm. In this article, measurement and calculation results performed with the 3D code HFSS for coupling factor evaluation will be presented in details.  
 
THPPC013 Progress on Coupled RFQ-SFRFQ Accelerator for Materials Irradiation Research cavity, ion-source, ion, ECR 3302
 
  • Z. Wang, J.E. Chen, S.L. Gao, Z.Y. Guo, Y.R. Lu, S.X. Peng, W.L. Xia, X.Q. Yan, J. Zhao, K. Zhu
    PKU/IHIP, Beijing, People's Republic of China
  
  Funding: Project supported by the National Natural Science Foundation of China (Grant No.10905003) and China Postdoctoral Science Foundation.
There is always high interest to study material irradiation damage effects based on accelerators. The bombardment of solids with high energy particles causes some changes in many important engineering properties. By implanting helium ions, it may be possible to simulate the damage process occurs in vessels and unravel the complexμstructural andμchemical evolutions that are expected in advanced nuclear energy systems. A materials irradiation facility based on coupled RFQ-SFRFQ accelerator will be built in Peking University, attribute to the commissioning of prototype SFRFQ accelerator, we have coupled the SFRFQ electrodes and the traditional RFQ electrodes in one cavity to form a more compact accelerator which can provide helium beam with energy of 0.8MeV for materials irradiation research. 		 
 
THPPC014 Commissioning Status of the 3 MeV RFQ for the Compact Pulsed Hadron Source (CPHS) at Tsinghua University proton, vacuum, ion, status 3305
 
  • Q.Z. Xing, Y.J. Bai, D.T. Bin, J.C. Cai, C. Cheng, L. Du, Q. Du, C. Jiang, Q. Qiang, D. Wang, X.W. Wang, Z.F. Xiong, S.Y. Yang, H.Y. Zhang, S.X. Zheng
    TUB, Beijing, People's Republic of China
  • J.H. Billen
    TechSource, Santa Fe, New Mexico, USA
  • W.Q. Guan, Y. He, J. Li
    NUCTECH, Beijing, People's Republic of China
  • X.L. Guan
    Tsinghua University, Beijing, People's Republic of China
  • J. Stovall
    CERN, Geneva, Switzerland
  • L.M. Young
    AES, Medford, NY, USA
  
  Funding: Work supported by the “985 Project” of the Ministry of Education of China.
We present, in this paper, the commissioning status of a Radio Frequency Quadrupole (RFQ) accelerator for the Compact Pulsed Hadron Source (CPHS) at Tsinghua University. In 2012 the 3-meter-long RFQ will deliver 3 MeV protons to the downstream High Energy Beam Transport (HEBT) with the peak current of 50 mA, pulse length of 0.5 ms and beam duty factor of 2.5%. Braze of the vanes was completed in September, 2011. The final field tuning of the whole cavity was completed in October, 2011. Initial commissioning will be underway at the beginning of 2012. 		 
 
THPPC015 Design of a Four-vane 325 MHz RFQ Cold Model at Tsinghua University cavity, dipole, resonance, simulation 3308
 
  • L. Du, J.C. Cai, X. Guan, Q.Z. Xing
    TUB, Beijing, People's Republic of China
  
  Funding: Work supported by National Natural Science Foundation of China (Project 11175096).
The design of a Radio Frequency Quadrupole (RFQ) accelerator cold model at Tsinghua University is presented in this paper. The 1-meter-long aluminium cold model is chosen to be the same as the low-energy part of the 3-meter-long RFQ for the Compact Pulsed Hadron Source (CPHS) project at Tsinghua University. This cold model will be used mainly for the RFQ field study and education. It will work at the RF frequency of 325 MHz. All the simulations are finished by the SUPERFISH and MAFIA codes. 		 
 
THPPC034 Design and Analysis of the PXIE CW Radio-frequency Quadrupole (RFQ) cavity, controls, quadrupole, vacuum 3359
 
  • S.P. Virostek, M.D. Hoff, A.R. Lambert, D. Li, J.W. Staples
    LBNL, Berkeley, California, USA
  • G.V. Romanov
    Fermilab, Batavia, USA
  • C. Zhang
    IAP, Frankfurt am Main, Germany
  
  Funding: This work is supported by the Office of Science, United States Department of Energy under DOE contract DE-AC02-05CH11231.
The Project X Injector Experiment (PXIE) will be a prototype front end of the Project X accelerator proposed by Fermilab. PXIE will consist of an H− ion source, a low-energy beam transport (LEBT), a radio-frequency quadrupole (RFQ) accelerator, a medium-energy beam transport (MEBT) and a section of superconducting cryomodules that will accelerate the beam from 30 keV to 30 MeV. LBNL has developed an RFQ design for PXIE with fabrication scheduled to begin before the end of CY 2012. The chosen baseline design is a four-vane, 4.4 m long CW RFQ with a resonant frequency at 162.5 MHz (2.4 wavelengths long). The RFQ will provide bunching and acceleration of a nominal 5 mA H− beam to 2.1 MeV. The relatively low wall power density results in wall power losses that are less than 100 kW. The beam dynamics design has been optimized to allow for more than 99% beam capture with exceptionally low longitudinal emittance. The RFQ mechanical design and the results of RF and thermal analyses are presented here. 		 
 
THPPD045 High Temperature Superconducting Magnets for Efficient Low Energy Beam Transport Systems solenoid, ion, emittance, vacuum 3614
 
  • J.H. Nipper, G. Flanagan, R.P. Johnson
    Muons, Inc, Batavia, USA
  • M. Popovic
    Fermilab, Batavia, USA
  
  Modern ion accelerators and ion implantation systems need very short, highly versatile, Low Energy Beam Transport (LEBT) systems. The need for reliable and continuous operation requires LEBT designs to be simple and robust. The energy efficiency of available high temperature superconductors (HTS), with efficient and simple cryocooler refrigeration, is an additional attraction. Innovative, compact LEBT systems based on solenoids designed and built with high-temperature superconductor will be developed using computer models and prototyped. The parameters will be chosen to make this type of LEBT useful in a variety of ion accelerators, ion implantation systems, cancer therapy synchrotrons, and research accelerators, including the ORNL SNS. The benefits of solenoids made with HTS will be evaluated with analytical and numerical calculations for a two-solenoid configuration, as will be used in the SNS prototype LEBT that will replace the electrostatic one at SNS, and a single solenoid configuration, as was proposed for the Fermilab proton driver that will be most applicable to ion implantation applications.  
 
THPPP017 ELENA: From the First Ideas to the Project antiproton, electron, extraction, vacuum 3764
 
  • G. Tranquille, P. Belochitskii, T. Eriksson, S. Maury
    CERN, Geneva, Switzerland
  • W. Oelert
    Forschungszentrum Jülich GmbH, Institut fur Nuklearchemie (INC), Jülich, Germany
  
  Successful commissioning of the CERN Antiproton Decelerator (AD) in 2000 was followed by significant progress in the creation of antihydrogen atoms. The extraction energy of the decelerated antiprotons is nevertheless very high compared to that required by experiments and results in a trapping efficiency of only 0.1% to 3%. To improve this value by an order of magnitude the study of an Extra Low ENergy Antiproton ring (ELENA) started in 2003 and was approved as a CERN construction project in 2011. During these years the choice of the main machine parameters such as the beam extraction energy, emittance and bunch length were defined, taking into account requests from the physics community. The main challenges were also identified, such as dealing with the large space charge tune, the ultra high vacuum required and the tight requirements for the electron cooler. Housing the ELENA ring within the AD hall significantly reduced the project cost as well as simplifying the beam transfer from AD to ELENA and from ELENA to the existing experimental areas. This contribution will follow ELENA from its beginnings to the final, approved project proposal.  
 
THPPP031 RF Design of ESS RFQ simulation, coupling, cavity, linac 3800
 
  • O. Piquet, M. Desmons, A. France
    CEA/DSM/IRFU, France
  • O. Delferrière
    CEA/IRFU, Gif-sur-Yvette, France
  
  The low energy front end of ESS is based on a 352 MHz, 5-m long Radiofrequency Quadrupole (RFQ) cavity. It will accelerate and bunch proton beams from 75 keV to 3 MeV. The beam current is 50 mA (75 mA as an upgrade scenario) for 4% duty cycle. A complete RF analysis of the ESS RFQ has been performed using 3D RF simulating codes and a RFQ 4-wire transmission line model. Proposed RFQ is a 4 vane-type structure where 2D cross-section is optimized for lower power dissipation, while featuring simple geometrical shape suitable for easy machining. RF calculations are performed for the whole RFQ, and mainly for the following parts: end cells, vacuum port, tuners and RF coupling ports. Power losses are particularly calculated in order to achieve Thermo-mechanical calculations.  
 
THPPP034 Optimization of a CW RFQ Prototype simulation, impedance, linac, DTL 3809
 
  • U. Bartz, J. Gerbig, H.C. Lenz, A. Schempp
    IAP, Frankfurt am Main, Germany
  
  A short RFQ prototype was built for RF-tests of high power RFQ structures. We studied thermal effects to determine critical points of the design. HF-simulations with CST Microwave Studio and measurements were done. The cw-tests with 20 kW/m RF-power and simulations of thermal effects with ALGOR were finished successfully. The optimization of some details of the RF design is on focus now. Results and the status of the project will be presented  
 
THPPP037 Status of the 325 MHz 4-ROD RFQ simulation, dipole, HOM, linac 3815
 
  • B. Koubek, A. Schempp, J.S. Schmidt
    IAP, Frankfurt am Main, Germany
  • L. Groening
    GSI, Darmstadt, Germany
  
  For the FAIR project of GSI as part of the proton linac, a 325 MHz 4-ROD RFQ with an output energy of 3 MeV is planned. Due to the simulations regarding the RF design, a prototype of this RFQ was built. Measurements with this prototype to verify the simulation results have been done. In addition, simulations with increasing cell numbers and simulations concerning the boundary fields of the electrodes are presented in this paper.  
 
THPPP038 Simulations of the Influence of 4-Rod RFQ Elements on its Voltage Distribution simulation, resonance, linac, insertion 3818
 
  • J.S. Schmidt, B. Koubek, A. Schempp
    IAP, Frankfurt am Main, Germany
  
  The influence of tuning methods and other design elements of 4-rod-RFQs on the voltage distribution have been studied during the last months. Every change in the field geometry or the voltage distribution could for example lead to particle losses or a raise in the surface current on single parts of the RFQ. That’s why further research had to be done about the behavior of the 4-rod-RFQ especially in the comparison of structures at 100 or 200 MHz. The results of an analysis which is concentrated on simulations using CST Microwave Studio to evaluate the effects of the overhang of electrodes, modulation and piston tuners on the fields in the RFQ are presented in this paper.  
 
THPPP041 A CW High Charge State Heavy Ion RFQ Accelerator for SSC-LINAC Injector linac, resonance, focusing, ion 3826
 
  • G. Liu, J.E. Chen, S.L. Gao, Y.R. Lu, Z. Wang, X.Q. Yan, Q.F. Zhou, K. Zhu
    PKU/IHIP, Beijing, People's Republic of China
  • Y. He, C. Xiao, Y.Q. Yang, Y.J. Yuan, H.W. Zhao
    IMP, Lanzhou, People's Republic of China
  
  Funding: Supported by NSFC(11079001).
The cooler storage ring synchrotron CSR of HIRFL started running in 2008. The SFC (Sector Focusing Cyclotron) and SSC (Separator Sector Cyclotron) form an injector for the CSR. To improve beam intensity and/or injection efficiency, a new linear injector, the SSC-LINAC, for the SSC has been proposed to replace the existing SFC. The SSC-LINAC consists of an ECR ion source, LEBT, a RFQ, MEBT, and four IH-DTLs. This paper only represents the design research of the RFQ accelerator, which has a frequency of 53.667MHz. The ions up to uranium with ratio of mass-to-charge up to 7 are accelerated and injected into the CSR by the SSC-LINAC. The SSC-LINAC works on CW mode. The RFQ beam dynamic design study is based on 238U34+ beams with intensity of 0.5mA. The inter-vane voltage is 70kV with a maximum modulation factor of 1.93. It uses a 2.5m-long 4-rod structure to accelerate uranium ions from 3.728keV/u to 143keV/u with transmission efficiency of 94%. The RFQDYN code checks the transmission of different kinds of ions in the RFQ. The specific shunt impedance of RFQ is optimized to 438kΩ.m. The design of cavity tuning and the water cooling system are also included in this paper.
Corresponding authors: yrlu@pku.edu.cn, hey@impcas.ac.cn 		 
 
THPPP042 The First Step of RFQ Development in KBSI ion, quadrupole, emittance, dipole 3829
 
  • J.W. Ok, S. Choi, B.C. Kim, B.S. Lee, J.Y. Park, M. Won, J.H. Yoon
    Korea Basic Science Institute, Busan, Republic of Korea
  
  The RFQ for accelerating an ion beam is being developed in Korea Basic Science Institute (KBSI). The KBSI RFQ is designed to accelerate 1 mA lithium beam (Q/A=3/7) at 88 MHz. It is considered to be a 4-vane RFQ structure. The injection beam energy into RFQ is 12 keV/u, the output beam energy downstream from RFQ is 300 keV/u. The RFQ has to show stable operation, meet availability, and have the minimum losses so as to guarantee the best performance/cost ratio. At the first step, two dimensional geometry structure was studied using SUPERFISH code for the resonance frequency of quadrupole and dipole modes. Three dimensional field distributions were investigated by CST microwave studio. The beam dynamics in RFQ accelerator were studied using PARMTEQM code. Based on these results, the structural analysis should be studied and a cold model will be fabricated and investigated. The practical KBSI RFQ will be manufactured in next year.  
 
THPPP044 RF Set-up Scheme for PEFP DTL DTL, linac, proton, simulation 3835
 
  • J.-H. Jang, Y.-S. Cho, H.S. Kim, H.-J. Kwon
    KAERI, Daejon, Republic of Korea
  
  Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government.
The proton engineering frontier project (PEFP) is developing a 100-MeV proton linac which consists of a 50 keV injector, a 3-MeV radio frequency quadrupole (RFQ) and a 100-MeV drift tube linac (DTL). The installation of the linac was started in December 2011. The beam commissioning is scheduled for 2012. The phase scan signature method is a common technique to determine the rf set point including the amplitude and phase in DTL tanks. This work summarized the rf set-up scheme for PEFP DTL tanks by using the phase scan signature method. 		 
 
THPPP048 Linac4 - Low Energy Beam Measurements solenoid, emittance, ion, linac 3847
 
  • L.M. Hein, G. Bellodi, J.-B. Lallement, A.M. Lombardi, O. Midttun, P.A. Posocco, R. Scrivens
    CERN, Geneva, Switzerland
  
  Linac4 is a160 MeV normal-conducting linear accelerator for negative Hydrogen ions (H−), which will replace the 50 MeV proton Linac (Linac2) as linear injector for the CERN accelerators. The low energy part, comprising a 45 keV Low Energy Beam Transport system (LEBT), a 3 MeV Radiofrequency Quadrupole (RFQ) and a Medium Energy Beam Transport (MEBT) is being assembled in a dedicated test stand for pre-commissioning with a proton beam. During 2011 extensive measurements were done after the source and after the LEBT with the aim of preparing the RFQ commissioning and validating the simulation tools, indispensable for future source upgrades. The measurements have been thoroughly simulated with a multi-particle code, including 2D magnetic field maps, error studies, steering studies and the generation of beam distribution from measurements. Emittance, acceptance and transmission measurements will be presented and compared to the results of the simulations.  
 
THPPP051 Status of the RAL Front End Test Stand ion, ion-source, beam-transport, simulation 3856
 
  • A.P. Letchford, M.A. Clarke-Gayther, D.C. Faircloth, S.R. Lawrie
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • S.M.H. Alsari, M. Aslaninejad, A. Kurup, P. Savage
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  • J.J. Back
    University of Warwick, Coventry, United Kingdom
  • G.E. Boorman, A. Bosco
    Royal Holloway, University of London, Surrey, United Kingdom
  • C. Gabor, D.C. Plostinar
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • A. Garbayo
    AVS, Eibar, Gipuzkoa, Spain
  • S. Jolly
    UCL, London, United Kingdom
  • J.K. Pozimski
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  
  The Front End Test Stand (FETS) under construction at RAL is a demonstrator for front end systems of a future high power proton linac. Possible applications include a linac upgrade for the ISIS spallation neutron source, new future neutron sources, accelerator driven sub-critical systems, a neutrino factory etc. Designed to deliver a 60mA H-minus beam at 3MeV with a 10% duty factor, FETS consists of a high brightness ion source, magnetic low energy beam transport (LEBT), 4-vane 324MHz radio frequency quadrupole, medium energy beam transport (MEBT) containing a high speed beam chopper plus comprehensive diagnostics. This paper describes the current status of the project and future plans.  
 
THPPP052 Modelling the ISIS 70 MeV Linac DTL, linac, quadrupole, simulation 3859
 
  • D.C. Plostinar, C.R. Prior, G.H. Rees
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • A.P. Letchford
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • A.W. Mitchell
    University of Warwick, Coventry, United Kingdom
  
  The ISIS linac consists of four DTL tanks that accelerate a 50 pps, 20 mA H− beam up to 70 MeV before injecting it into an 800 MeV synchrotron. Over the last decades, the linac has proved to be a stable and reliable injector for ISIS, which is a significant achievement considering that two of the tanks are nearly 60 years old. At the time the machine was designed, the limited computing power available and the absence of modern modeling codes, made the creation of a complex simulation model almost impossible. However, over the last few years, computer tools have became an integral part of any accelerator design, so in this paper we present a beam dynamics model of the ISIS linac. A comparison between the simulation results and machine operation data will be discussed, as well as possible linac tuning scenarios and recommended upgrades based on the new model.  
 
THPPP053 The Manufacture and Assembly of the FETS RFQ alignment, vacuum, simulation, controls 3862
 
  • P. Savage, J.K. Pozimski
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  • A. Garbayo
    AVS, Eibar, Gipuzkoa, Spain
  • A.P. Letchford
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • D.S. Wilsher
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  
  The Rutherford Appleton Laboratory (RAL) Front End Test Stand (FETS) uses a 324 MHz 4-vane RFQ to accelerate H− ions from 65keV to 3MeV. The RFQ is a copper structure that has been designed as 4 nominally one metre long assemblies. Each assembly consists of 2 major vanes and 2 minor vanes that are bolted together and sealed using an O ring. The mechanical design for the FETS RFQ is complete and the manufacture is underway. In order to achieve the designed physics performance the vanes must be machined and assembled to high degree of accuracy. This requirement has demanded a tight synergy between the design, manufacture and metrology services. Together they have developed detailed procedures for the manufacturing, inspection, alignment and assembly phases. The key points of these procedures will be detailed in this paper.  
 
THPPP057 PXIE Optics and Layout focusing, cryomodule, cavity, solenoid 3871
 
  • V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A.V. Shemyakin, B.G. Shteynas, N. Solyak
    Fermilab, Batavia, USA
  
  The Project X Injector Experiment (PXIE) will serve as a prototype for the Project X front end. The aim is to validate the Project-X design and to decrease technical risks, known to be mainly related to the front end. PXIE will accelerate a 1 mA CW beam to about 25 MeV. It will consist of an ion source, LEBT, CW RFQ, MEBT, two SC cryomodules, a diagnostic section and a beam dump. A bunch-by-bunch chopper located in the MEBT section will allow formation of an arbitrary bunch structure. PXIE deviates somewhat from the current Project-X front end concept in that it provides additional instrumentation and relies on a reduced number of kickers for bunch chopping; the diagnostic section also include an RF separator to allow studying extinction of removed bunches. The paper discusses the main requirements and constraints motivating the facility layout and optics. Final adjustments to the Project X front end design, if needed, will be based on operational experience gained with PXIE.
Operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. 		 
 
THPPP058 PXIE: Project X Injector Experiment cryomodule, ion, solenoid, ion-source 3874
 
  • S. Nagaitsev, S.D. Holmes, R.D. Kephart, J.S. Kerby, V.A. Lebedev, C.S. Mishra, A.V. Shemyakin, N. Solyak, R.P. Stanek
    Fermilab, Batavia, USA
  • D. Li
    LBNL, Berkeley, California, USA
  • P.N. Ostroumov
    ANL, Argonne, USA
  
  A multi-MW proton facility, Project X has been proposed and is currently under development at Fermilab. As part of this development program, we are constructing a prototype of the front end of the Project X linac at Fermilab. The construction and successful operations of this facility will validate the concept for the Project X front end, thereby minimizing the primary technical risk element within the Project. The Project X Injector Experiment (PXIE) can be constructed over the period FY12-16 and will include an H− ion source, a CW 2.1-MeV RFQ and two SC cryomodules providing up to 30 MeV energy gain at an average beam current of 1 mA. Successful operations of the facility will demonstrate the viability of novel front end technologies that will find applications beyond Project X in the longer term.  
 
THPPP062 The Six-Cavity Test - Demonstrated Acceleration of Beam with Multiple RF Cavities and a Single Klystron cavity, controls, klystron, proton 3877
 
  • J. Steimel, J.-P. Carneiro, B. Chase, S. Chaurize, E. Cullerton, B.M. Hanna, R.L. Madrak, R.J. Pasquinelli, L.R. Prost, L. Ristori, V.E. Scarpine, P. Varghese, R.C. Webber, D. Wildman
    Fermilab, Batavia, USA
  
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The High Intensity Neutrino Source (HINS) ‘Six-Cavity Test’ has demonstrated the use of high power RF vector modulators to control multiple RF cavities driven by a single high power klystron to accelerate a non-relativistic beam. Installation of 6 cavities in the existing HINS beamline has been completed and beam measurements have started. We present data showing the energy stability of the 7 mA proton beam accelerated through the six cavities from 2.5 MeV to 3.4 MeV. 		 
 
THPPP064 Project X RFQ EM Design simulation, quadrupole, dipole, radio-frequency 3883
 
  • G.V. Romanov
    Fermilab, Batavia, USA
  • M.D. Hoff, D. Li, J.W. Staples, S.P. Virostek
    LBNL, Berkeley, California, USA
  
  Project X is a proposed multi-MW proton facility at Fermi National Accelerator Laboratory (FNAL). The Project X front-end would consist of an H− ion source, a low-energy beam transport (LEBT), a cw 162.5 MHz radio-frequency quadrupole (RFQ) accelerator, and a medium-energy beam transport (MEBT). Lawrence Berkeley National Laboratory (LBNL) and FNAL collaboration is currently developing the designs for various components in the Project X front end. This paper reports the detailed EM design of the cw 162.5 MHz RFQ that provides bunching of the 1-10 mA H− beam with acceleration from 30 keV to 2.1 MeV.  
 
THPPP065 The FNAL Injector Upgrade Status emittance, extraction, beam-transport, vacuum 3886
 
  • C.-Y. Tan, D.S. Bollinger, K.L. Duel, P.R. Karns, J.R. Lackey, W. Pellico, V.E. Scarpine, R.E. Tomlin
    Fermilab, Batavia, USA
  
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The new FNAL H− injector upgrade is currently being tested before installation in the Spring 2012 shutdown of the accelerator complex. This line consists of an H− source, low energy beam transport (LEBT) and 200 MHz RFQ. Beam measurements have been performed to validate the design before installation. The results of the beam measurements are presented in this paper. 		 
 
THPPP075 Present Status and Developments of the Linear IFMIF Prototype Accelerator (LIPAc) cavity, solenoid, linac, SRF 3910
 
  • A. Mosnier, P. Cara, R. Heidinger
    Fusion for Energy, Garching, Germany
  • P.-Y. Beauvais, S. Chel
    CEA/IRFU, Gif-sur-Yvette, France
  • A. Facco, A. Pisent
    INFN/LNL, Legnaro (PD), Italy
  • A. Ibarra, J. Molla
    CIEMAT, Madrid, Spain
  • V. Massaut, D. Vandeplassche
    SCK•CEN, Mol, Belgium
  • H. Matsumoto, G. Pruneri, Ch. Vermare
    IFMIF/EVEDA, Rokkasho, Japan
  • M. Sugimoto, H. Suzuki
    JAEA, Aomori, Japan
  
  The International Fusion Materials Irradiation Facility (IFMIF) aiming at generating materials irradiation test data for DEMO and future fusion power plants is based on an accelerator-driven, D-Li neutron source to produce high energy neutrons at sufficient intensity and irradiation volume. IFMIF Engineering Validation and Engineering Design Activities (EVEDA) have been conducted since mid 2007 in the framework of the Broader Approach Agreement and the scope of the project has been recently revised to set priority on the validation activities, especially on the Accelerator Prototype (LIPAc) with extending the duration up to mid 2017 in order to better fit the development of the challenging components and the commissioning of the whole accelerator. This paper summarizes the present status of the LIPAc, currently under construction at Rokkasho in Japan, outlines the engineering design and the developments of the major components, as well as the expected outcomes of the engineering work, associated with the experimental program.  
 
THPPP091 Status of the Project-X CW Linac Design linac, cryomodule, emittance, lattice 3948
 
  • J.-F. Ostiguy, P. Berrutti, J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, A. Saini, B.G. Shteynas, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, USA
  
  Superconducting CW linac was proposed for Project X to accelerate H− beam from 2.1 MeV to 3 GeV with nominal peak and average currents of respectively 5 mA and 1 mA. Linac built of 5 different families of resonators: half-wave, spoke (2), and elliptical (2) working at 162.5 MHz 325 MHz and 650 MHz to cover all energy range. Cavities and focusing elements are assembled in cryomodules. In baseline design all cryomodules are separated by short warm sections. It makes machine more reliable and maintainable and provide space for beam diagnostics and collimation. A long (~10m) gap between cryomodules at1 GeV is also being considered to provide space for beam extraction for nuclear experimental program. In paper we present the latest lattice of the linac baseline design and results of beam studies for this lattice. We briefly compare performance of the baseline design with alternative one without half-wave resonator section.  
 
THPPP092 Progress of the Front-End System Development for Project X at LBNL ion-source, ion, simulation, emittance 3951
 
  • D. Li, M.D. Hoff, Q. Ji, A.R. Lambert, T. Schenkel, J.W. Staples, S.P. Virostek
    LBNL, Berkeley, California, USA
  • S. Nagaitsev, L.R. Prost, G.V. Romanov, A.V. Shemyakin
    Fermilab, Batavia, USA
  • C. Zhang
    IAP, Frankfurt am Main, Germany
  
  Funding: This work is supported by the Office of Science, United States Department of Energy under DOE contract DE-AC02-05CH11231.
A multi-MW proton facility, Project X has been proposed and is currently under development at Fermilab. Project X is a key accelerator complex for intensity frontier of future high energy physics programs in the US. In collaboration with Fermilab, LBNL takes the responsibility in the development and design studies of the front-end system for Project X. The front-end system would consist of H− ion source(s), low-energy beam transport (LEBT), 162.5 MHz normal conducting CW Radio-Frequency-Quadrupole (RFQ) accelerator, medium-energy beam transport (MEBT), and beam chopper(s). In this paper, we will review and present recent progress of the front-end system studies, which will include the RFQ beam dynamics design, RF structure design, thermal and mechanical analyses and fabrication plan, LEBT simulation studies and concept for LEBT chopper. 		 
 
THPPR041 The Conceptual Design of the Shielding Layout and Beam Absorber at the PXIE radiation, shielding, cryomodule, proton 4065
 
  • Y.I. Eidelman, J.S. Kerby, V.A. Lebedev, J.R. Leibfritz, A.F. Leveling, S. Nagaitsev, R.P. Stanek
    Fermilab, Batavia, USA
  
  The Project X Injector Experiment (PXIE) is a prototype of the Project X front end. A 30 MeV 50 kW H− beam will be used to validate the design concept of the Project X. This paper discusses a design of the accelerator enclosure radiation shielding and the beam dump. Detailed energy deposition and activation simulation were performed with the MARS15 code. The simulation results guided the design of the installation enclosure.  
 
THPPR067 A Conceptual 3-GeV LANSCE Linac Upgrade for Enhanced Proton Radiography proton, linac, neutron, cryomodule 4130
 
  • R.W. Garnett, F.E. Merrill, J.F. O'Hara, D. Rees, L. Rybarcyk, T. Tajima, P.L. Walstrom
    LANL, Los Alamos, New Mexico, USA
  
  Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
A conceptual design of a 3-GeV linac upgrade that would enable enhanced proton radiography at LANSCE is presented. The upgrade is based on the use of superconducting accelerating cavities to increase the present LANSCE linac output energy from 800 MeV to 3 GeV. The LANSCE linac at Los Alamos National Laboratory currently provides H− and H+ beams to several user facilities that support Isotope Production, NNSA Stockpile Stewardship, and Basic Energy Science programs. Required changes to the front-end and to the RF systems to meet the new performance goals, and changes to the existing beam switchyard to maintain operations for a robust user program are also described.