02 Proton and Ion Accelerators and Applications
2A Proton Linac Projects
Paper Title Page
SUPB012 Status of CH Cavity and Solenoid Design of the 17 MeV Injector for MYRRHA 29
 
  • D. Mäder, H. Klein, H. Podlech, U. Ratzinger, C. Zhang
    IAP, Frankfurt am Main, Germany
 
  Funding: This work has been supported by the EU (FP7 MAX contract number 269565)
The multifunctional subcritical reactor MYRRHA (Multi-purpose hybrid research reactor for high-tech applications) will be an accelerator driven system (ADS) located in Mol (Belgium). The first accelerating section up to 17 MeV is operated at 176 MHz and consists of a 4-rod-RFQ followed by two room temperature CH cavities with integrated triplet lenses and four superconducting CH structures with intertank solenoids. Each room temperature CH cavity provides about 1 MV effective voltage gain using less than 30 kW of RF power. The superconducting resonators have been optimized for electric peak fields below 30 MV/m and magnetic peak fields below 30 mT. For save operation of the superconducting resonators the magnetic field of the intertank solenoids has to be well shielded towards the CH cavity walls. Different coil geometries have been compared to find the ideal solenoid layout.
 
 
SUPB013 The Beam Commissioning Plan of Injector II in C-ADS 32
 
  • Z.J. Wang, Y. He, H. Jia, C. Li, S.H. Liu, W. Wu, X.B. Xu, B. Zhang, H.W. Zhao
    IMP, Lanzhou, People's Republic of China
 
  The design work of the Injector II, which is 10 MeV proton linac, in C-ADS project is being finished and some key elements are being fabricated. Now it is necessary to definite the operation mode of beam commissioning, including the selection of the beam current, pulse length and repetition frequency. Also the beam commissions plan should be specified. The beam commissions procedures is simulated with t-mode code GPT. In this paper, the general beam commissioning plan of Injector II in CIADS and simulation results of commissions procedures are presented.  
 
MO1A01 Operational Experience and Future Goals of the SARAF Linac at SOREQ 100
 
  • D. Berkovits, A. Arenshtam, Y. Ben Aliz, Y. Buzaglo, O. Dudovich, Y. Eisen, I. Eliyahu, G. Feinberg, I. Fishman, I. Gavish, I.G. Gertz, A. Grin, S. Halfon, D. Har-Even, Y.F. Haruvy, T. Hirsch, D. Hirschmann, Z. Horvitz, B. Kaizer, D. Kijel, A. Kreisel, G. Lempert, J. Luner, I. Mardor, A. Perry, E. Reinfeld, J. Rodnizki, G. Shimel, A. Shor, I. Silverman, L. Weissman, E. Zemach
    Soreq NRC, Yavne, Israel
 
  SARAF-phase 1 at SOREQ, with its single 6 half-wave resonators cryomodule, is the first high current, superconducting low-beta linac in operation and it is presently delivering cw proton beams in the mA range. A phase 2 is foreseen for this linac which will allow acceleration up to 40 MeV of 2 mA cw proton and deuteron beams. The project status, the operational experience and the future goals of SARAF should be described.  
slides icon Slides MO1A01 [3.276 MB]  
 
MO2A02 Increased Understanding of Beam Losses from the SNS Linac Proton Experiment 115
 
  • J. Galambos, A.V. Aleksandrov, M.A. Plum, A.P. Shishlo
    ORNL, Oak Ridge, Tennessee, USA
  • E. Laface
    ESS, Lund, Sweden
  • V.A. Lebedev
    Fermilab, Batavia, USA
 
  The SNS Linac has been in operation for 6 years, with its power being gradually increased. A major operation goal is the decrease of beam loss. It has been recently suggested that intra- H–beam stripping contributes significantly to beam losses in an H linac. This was tested experimentally at SNS by accelerating a proton beam. Experimental analysis results are in good agreement with the theoretical estimates. In this paper we present the operational status and experience at the SNS linac, with emphasis on understanding beam loss in terms of intra-H–beam stripping.  
slides icon Slides MO2A02 [12.869 MB]  
 
TU1A02
Status of Fermilab Project X  
 
  • S. Nagaitsev, S. Henderson
    Fermilab, Batavia, USA
 
  Project X, a high-power proton facility, will support world-leading programs in long base line neutrino physics, the physics of rare processes, and nuclear studies. It will be unique among accelerator facilities worldwide in its flexibility to support multiple physics programs simultaneously with MW class beams at the intensity frontier. Project X is based on a 3 GeV continuous-wave superconducting H linac. Further acceleration to 8 GeV, and injection into Fermilab's existing Recycler/Main Injector complex, will support long-baseline neutrino experiments. Project X will provide ~3 MW of total beam power to the 3 GeV program, simultaneously with ≥ 2 MW to a neutrino production target at 60-120 GeV. This talk will describe the Reference Design of Project X and status of the R&D program.  
slides icon Slides TU1A02 [4.706 MB]  
 
TU1A05 Status and Commissioning Plan of the PEFP 100-MeV Linear Accelerator 422
 
  • H.-J. Kwon, Y.-S. Cho, J.-H. Jang, D.I. Kim, H.S. Kim, B.-S. Park, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun
    KAERI, Daejon, Republic of Korea
 
  Funding: Works supported by the Ministry of Education, Science and Technology of Korean Government.
One of the goals of the Proton Engineering Frontier Project (PEFP) is to develop a 100 MeV proton linear accelerator, which consists of 50 keV proton injector, 3 MeV radio frequency quadrupole (RFQ), 20 MeV/100 MeV drift tube linac (DTL) and 20 MeV/100 MeV beam lines. The 100 MeV linear accelerator and beam line components have been installed in the tunnel and experimental hall. After the completion of the utility commissioning, the commissioning of the accelerator starts with a goal of the beam delivery to the 100 MeV target room located at the end of the beam line in 2012. In this paper, the status and commissioning plan of the PEFP 100 MeV linear accelerator are presented.
 
slides icon Slides TU1A05 [6.795 MB]  
 
TH2A01 The ESS Linac Design 768
 
  • M. Lindroos, H. Danared, C. Darve, D.P. McGinnis, S. Molloy
    ESS, Lund, Sweden
 
  The European Spallation Source (ESS) is a 5 MW, 2.5 MeV long pulse proton machine. It represents a big jump in power compare to the existing spallation facilities. The design phase is well under way, with the delivery of a Conceptual Design Report expected in 2012, and a Technical Design Report in 2013. Why and how the 5 MW goal influences the parameter choice will be describe.  
slides icon Slides TH2A01 [5.667 MB]  
 
THPLB01 Linac Construction for China Spallation Neutron Source 807
 
  • S. Fu, J. Li, H.C. Liu, H.F. Ouyang, X. Yin
    IHEP, Beijing, People's Republic of China
 
  Construction of China Spallation Neutron Source(CSNS) has been launched in September 2011. CSNS accelerator will provide 100kW proton beam on a target at beam energy of 1.6GeV. It consists of an 80MeV H linac and 1.6GeV rapid cycling synchrotron. Based on the prototyping experience, CSNS linac, including the front end and four DTL tanks, has finalized the design and started procurement. In this paper, we will first present an outline of the CSNS accelerator in its design and construction plan. Then the major prototyping results of the linac will be presented. Finally the linac construction progress in recent will be updated.  
slides icon Slides THPLB01 [1.969 MB]  
 
THPLB02 Performance of Ferrite Vector Modulators in the LLRF system of the Fermilab HINS 6-Cavity Test 810
 
  • P. Varghese, B.W. Barnes, B. Chase, E. Cullerton, C.C. Tan
    Fermilab, Batavia, USA
 
  The High Intensity Neutrino Source (HINS) 6-cavity test is a part of the Fermilab HINS Linac R&D program for a low energy, high intensity proton/H linear accelerator. One of the objectives of the 6-cavity test is to demonstrate the use of high power RF Ferrite Vector Modulators(FVM) for independent control of multiple cavities driven by a single klystron. The beamline includes an RFQ and six cavities. The LLRF system provides a primary feedback loop around the RFQ and the distribution of the regulated klystron output is controlled by secondary learning feed-forward loops on the FVMs for each of the six cavities. The feed-forward loops provide pulse to pulse correction to the current waveform profiles of the FVM power supplies to compensate for beam-loading and other disturbances. The learning feed-forward loops are shown to successfully control the amplitude and phase settings for the cavities well within the 1 % and 1 degree requirements specified for the system.  
slides icon Slides THPLB02 [1.610 MB]  
 
THPLB03 Front-End Linac Design and Beam Dynamics Simulations for MYRRHA 813
 
  • C. Zhang, H. Klein, D. Mäder, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede, M. Vossberg
    IAP, Frankfurt am Main, Germany
 
  Funding: Funded by the European Atomic Energy Community’s (Euratom) 7th Framework Programme under Grant Agreement n°269565.
A 17MeV, 176MHz, and CW (Continuous Wave) proton linac is being developed as the front end of the driver accelerator for the MYRRHA facility in Mol, Belgium. Based on the promising preliminary design, further simulation and optimization studies have been performed with respect to code benchmarking, RFQ simulation using realistic LEBT output distributions, and an updated CH-DTL design with more detailed inter-tank configurations. This paper summarizes the new results.
 
slides icon Slides THPLB03 [1.292 MB]  
 
THPLB04 Preliminary Study of Proton Beam Transport in a 10 MeV Dielectric Wall Accelerator 816
 
  • J. Zhu, S. Chen, J. Deng, Y. Shen, J. Shi, W.D. Wang, L.S. Xia, H. Zhang, L.W. Zhang
    CAEP/IFP, Mainyang, Sichuan, People's Republic of China
 
  Funding: Nuclear Energy Technology Development project; National Natural Science Foundation of China (11035004)
A novel proton accelerator based on Dielectric Wall Accelerator (DWA) technology is being developed at Institute of Fluid Physics (IFP). The accelerating gradient will be 20 MV/m or even higher based on current high gradient insulator (HIG) performance. Theoretical study and numerical simulation of accelerating the proton beam to 10 MeV by virtual traveling wave method is presented in this paper. The beam dynamics under accelerating pulse with or without flattop is discussed.
 
slides icon Slides THPLB04 [1.191 MB]  
 
THPLB05 R&D Activities on High Intensity Superconducting Proton Linac at RRCAT 819
 
  • S.C. Joshi, J. Dwivedi, P.D. Gupta, P.R. Hannurkar, P. Khare, P.K. Kush, G. Mundra, A. Puntambekar, S.B. Roy, P. Shrivastava
    RRCAT, Indore (M.P.), India
 
  Raja Ramanna Centre for Advanced Technology (RRCAT), Indore has taken up a program on development of 1 GeV high intensity superconducting proton linac for Spallation Neutron Source. This will require several multi-cell superconducting cavities operating at different RF frequencies. To start with, a number of single-cell prototype cavities at 1.3 GHz have been developed in high RRR bulk niobium. These single-cell cavities have exhibited high quality factor and accelerating gradients. Superconducting properties of niobium are being studied for varying composition of impurities and different processing conditions. Development activity on solid state RF amplifiers to power the SCRF cavities at various RF frequencies is being pursued. A building has been constructed to house the SCRF cavity fabrication and processing facility. To characterize SCRF cavity, a 2 K Vertical Test Stand is being set up including a 2 K cryostat, RF power supply and data acquisition system. Design activities for cryomodule and large 2 K cryostat for Horizontal Test Stand are also under progress. The paper will discuss the status of above R&D activities and infrastructure development at RRCAT.  
slides icon Slides THPLB05 [1.614 MB]  
 
THPB002 Preliminary Study of Proton Beam Transport in a 10 MeV Dielectric Wall Accelerator 840
 
  • J. Zhu, S. Chen, J. Deng, Y. Shen, J. Shi, W.D. Wang, L.S. Xia, H. Zhang, L.W. Zhang
    CAEP/IFP, Mainyang, Sichuan, People's Republic of China
  • Y. Liu
    Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, People's Republic of China
 
  Funding: Nuclear Energy Technology Development project; National Natural Science Foundation of China (11035004)
A novel proton accelerator based on Dielectric Wall Accelerator (DWA) technology is being developed at Institute of Fluid Physics (IFP). The accelerating gradient will be 20 MV/m or even higher based on current high gradient insulator (HIG) performance. Theoretical study and numerical simulation of accelerating the proton beam to 10 MeV by virtual traveling wave method is presented in this paper. The beam dynamics under accelerating pulse with or without flattop is discussed.
 
 
THPB003 R&D Activities on High Intensity Superconducting Proton Linac at RRCAT 843
 
  • S.C. Joshi, J. Dwivedi, P.D. Gupta, P.R. Hannurkar, P. Khare, P.K. Kush, G. Mundra, A. Puntambekar, S.B. Roy, P. Shrivastava
    RRCAT, Indore (M.P.), India
 
  Raja Ramanna Centre for Advanced Technology (RRCAT), Indore has taken up a program on development of 1 GeV high intensity superconducting proton linac for Spallation Neutron Source. This will require several multi-cell superconducting cavities operating at different RF frequencies. To start with, a number of single-cell prototype cavities at 1.3 GHz have been developed in high RRR bulk niobium. These single-cell cavities have exhibited high quality factor and accelerating gradients. Superconducting properties of niobium are being studied for varying composition of impurities and different processing conditions. Development activity on solid state RF amplifiers to power the SCRF cavities at various RF frequencies is being pursued. A building has been constructed to house the SCRF cavity fabrication and processing facility. To characterize SCRF cavity, a 2 K Vertical Test Stand is being set up including a 2 K cryostat, RF power supply and data acquisition system. Design activities for cryomodule and large 2 K cryostat for Horizontal Test Stand are also under progress. The paper will discuss the status of above R&D activities and infrastructure development at RRCAT.  
 
THPB004 Current Status of the RAL Front End Test Stand (FETS) Project 846
 
  • D.C. Plostinar, C. Gabor
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • S.M.H. Alsari, M. Aslaninejad, A. Kurup, J.K. Pozimski, 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
  • M.A. Clarke-Gayther, D.C. Faircloth, S.R. Lawrie, A.P. Letchford
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • S. Jolly
    UCL, London, United Kingdom
 
  The UK proton accelerator strategy aims to develop a viable high power proton driver with applications including spallation neutrons, the neutrino factory and ADSR. An essential first ingredient, identified as one of the main UK R&D accelerator projects, is the Front End Test Stand (FETS) at the Rutherford Appleton Laboratory (RAL), aimed at producing a high quality, high current, cleanly chopped H beam. Through its component parts, FETS has triggered development of a high brightness, 60 mA H ion source, a three-solenoid Low Energy Beam Transport line (LEBT), a 3 MeV four-vane Radio-Frequency Quadrupole (RFQ) and a Medium Energy Beam Transport line (MEBT) with a high speed chopper. The project is well advanced and when operational should be sufficiently versatile to explore a range of operating conditions. In this paper we present the current status of the construction, and plans for operation, experiments and future development.  
 
THPB005 Front-End Linac Design and Beam Dynamics Simulations for MYRRHA 849
 
  • C. Zhang, H. Klein, D. Mäder, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede, M. Vossberg
    IAP, Frankfurt am Main, Germany
 
  Funding: Funded by the European Atomic Energy Community’s (Euratom) 7th Framework Programme under Grant Agreement n°269565.
A 17MeV, 176MHz, and CW (Continuous Wave) proton linac is being developed as the front end of the driver accelerator for the MYRRHA facility in Mol, Belgium. Based on the promising preliminary design, further simulation and optimization studies have been performed with respect to code benchmarking, RFQ simulation using realistic LEBT output distributions, and an updated CH-DTL design with more detailed inter-tank configurations. This paper summarizes the new results.
 
 
THPB006 Post Acceleration of Laser-generated Proton Bunches by a CH-DTL 852
 
  • A. Almomani, M. Droba, I. Hofmann, U. Ratzinger
    IAP, Frankfurt am Main, Germany
 
  Laser driven proton beam sources applying the TNSA process show interesting features in terms of energy and proton number per bunch. This makes them attractive as injectors into RF linacs at energies as high as 10 MeV or beyond. The combination shows attractive features like a very high particle number in a single bunch from the source and the flexibility and reliability of the rf linac to match the needs of a specified application. The approach aims on a very short matching section from the source target into the rf linac by one pulsed solenoid lens only. A crossbar H-type (CH - structure) is suggested because of its high acceleration gradient and efficiency at these beam energies. It is intended to realize the first cavity of the proposed CH - linac and to demonstrate the acceleration of a laser generated proton bunch within the LIGHT collaboration at GSI Darmstadt. Detailed beam and field simulations will be presented.  
 
THPB007 A Pulsed Linac Front-end for ADS Applications 855
 
  • U. Ratzinger, H. Podlech, A. Schempp, K. Volk
    IAP, Frankfurt am Main, Germany
  • U. Hagen, O. Heid, T.J.S. Hughes
    Siemens AG, Erlangen, Germany
  • H. Hoeltermann
    BEVATECH OHG, Offenbach/Main, Germany
 
  Quite a number of projects worldwide develop proton driver linacs for neutron sources and other accelerator driven systems. One trend is to use a high duty factor and superconducting cavities as much as possible. Alternatively, one can aim on short duty factor and count on a continuing rapid development of pulsed rf amplifiers based on power transistor technology. A 500 mA, 5 % duty factor layout of a proton injector is presented, consisting of a filament driven volume ion source, of a 150 keV transport section and of a 4 m long 162 MHz RFQ up to 2 MeV beam energy. Beam dynamics results as well as the technical design will be shown.  
 
THPB008 A Coupled RFQ-IH Cavity for the Neutron Source FRANZ 858
 
  • M. Heilmann, O. Meusel, D. Mäder, U. Ratzinger, A. Schempp, M. Schwarz
    IAP, Frankfurt am Main, Germany
 
  The Frankfurt neutron source FRANZ will deliver neutrons in the energy range from 1 to 500 keV with high pulsed intensities. A 2 MeV proton beam will produce protons via the 7Li(p,n)7Be reaction. The 175 MHz accelerator cavity consists of a 4-rod-RFQ coupled with an 8 gap interdigital H-type drift tube section, the total cavity length being 2.3m. The combined cavity will be powered by one RF amplifier to reduce investment and operation costs. The inductive power coupler will be at the RFQ part. The coupling into the IH - section is provided through a large aperture - mainly inductively. By CST - MWS - simulations as well as by an RF - model the voltage tuning along the cavity was investigated, and with special care the balance between both cavity sections. A first set of RFQ electrodes should allow to reach beam currents up to 50 mA in cw operation: The beam is pulsed with 100 ns, 250 kHz, while the cavity has to be operated cw due to the high rep. rate. The layout of the cavity cooling aims on a maximum accessible heat load of 200 kW.  
 
THPB009 Status of CH Cavity and Solenoid Design of the 17 MeV Injector for MYRRHA 861
 
  • D. Mäder, H. Klein, H. Podlech, U. Ratzinger, C. Zhang
    IAP, Frankfurt am Main, Germany
 
  Funding: This work has been supported by the EU (FP7 MAX contract number 269565)
The multifunctional subcritical reactor MYRRHA (Multi-purpose hybrid research reactor for high-tech applications) will be an accelerator driven system (ADS) located in Mol (Belgium). The first accelerating section up to 17 MeV is operated at 176 MHz and consists of a 4-rod-RFQ followed by two room temperature CH cavities with integrated triplet lenses and four superconducting CH structures with intertank solenoids. Each room temperature CH cavity provides about 1 MV effective voltage gain using less than 30 kW of RF power. The superconducting resonators have been optimized for electric peak fields below 30 MV/m and magnetic peak fields below 30 mT. For save operation of the superconducting resonators the magnetic field of the intertank solenoids has to be well shielded towards the CH cavity walls. Different coil geometries have been compared to find the ideal solenoid layout.
 
 
THPB010 Progress in the Construction of Linac4 at CERN 864
 
  • M. Vretenar, L. Arnaudon, P. Baudrenghien, G. Bellodi, C. Bertone, Y. Body, J.C. Broere, O. Brunner, M.C.L. Buzio, C. Carli, J.-P. Corso, J. Coupard, A. Dallocchio, N. Dos Santos, J.-F. Fuchs, A. Funken, R. Garoby, F. Gerigk, L. Hammouti, K. Hanke, J. Hansen, I. Kozsar, J.-B. Lallement, J. Lettry, A.M. Lombardi, L.A. Lopez Hernandez, C. Maglioni, S.J. Mathot, B. Mikulec, D. Nisbet, M.M. Paoluzzi, B. Puccio, U. Raich, S. Ramberger, F. Roncarolo, C. Rossi, N. Schwerg, R. Scrivens, G. Vandoni, J. Vollaire, R. Wegner, S. Weisz, Th. Zickler
    CERN, Geneva, Switzerland
 
  As first step of the LHC luminosity upgrade program CERN is building a new 160 MeV H¯ linear accelerator, Linac4, to replace the ageing 50 MeV Linac2 as injector to the PS Booster (PSB). Linac4 is an 86-m long normal-conducting linac made of a 3 MeV injector followed by 22 accelerating cavities of three different types. The general service infrastructure has been installed in the new tunnel and surface building and its commissioning is progressing; high power RF equipment is being installed in the hall and installations in the tunnel will start soon. Construction of the accelerator parts is in full swing involving industry, the CERN workshops and a network of international collaborations. The injector section including a newly designed and built H¯ source, a 3-m long RFQ and a chopping line is being commissioned in a dedicated test stand. Beam commissioning of the linac will take place in steps of increasing energy between 2013 and 2014. From end of 2014 Linac4 could deliver 50 MeV protons in case of Linac2 failure, while 160 MeV H¯ could be injected into the PSB from end of 2015; the exact start of the LHC shut-down required for connection will be coordinated with its experiments.  
 
THPB011 Linac4 45 keV Proton Beam Measurements 867
 
  • G. Bellodi, V.A. Dimov, L.M. Hein, J.-B. Lallement, A.M. Lombardi, O. Midttun, R. Scrivens
    CERN, Geneva, Switzerland
  • P.A. Posocco
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
 
  Linac4 is a 160 MeV normal-conducting H linear accelerator, which will replace the 50 MeV proton Linac (Linac2) as injector for the CERN proton complex. Commissioning of the low energy part - H source, a 45 keV Low Energy Beam Transport line (LEBT), a 3 MeV RFQ and a Medium Energy Beam Transport (MEBT) line - will start in fall 2012 on a dedicated test stand installation. In preparation to this, preliminary measurements were taken in the past few months using a 45 keV proton source and a temporary LEBT setup, with the aim of characterising the output beam by comparison with simulations. This also allowed a first verification of the diagnostics instrumentation and acquisition software tools. Measurements of beam profile, emittance and intensity were taken after the source, after the first and after the second LEBT solenoids respectively. Particle distributions were reconstructed from emittance scans and used as input to simulation studies of the beam transport through the line. Comparison of the results with the measurements allowed an experimental validation of the LEBT (in terms of misalignments and calibration points) and qualification of the beam at the source output.  
 
THPB012 High Resolution Emittance Measurements at SNS Front End 870
 
  • A.P. Zhukov, A.V. Aleksandrov
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
Spallation Neutron Source (SNS) linac accelerates an H beam from 2.5MeV up to 1GeV. Recently the emittance scanner in the MEBT (2.5 MeV) was upgraded. In addition to the slit - harp measurement we now can use a slit installed on the same actuator as the harp. In combination with a faraday cup located downstream in DTL part of the linac it represents a classical slit-slit emittance measurement device. While a slit – slit scan takes much longer time, it is immune to harp related problems such as wire cross talk and thus looks promising for accurate halo measurements. Time resolution of the new device seems to be sufficient to estimate amount of the beam in the chopper gap (the scanner is downstream of the chopper) and probably measure its emittance. The paper describes initial measurements with new device and some model validation data.
 
 
THPB013 Diagnostics Tools for Beam Halo Investigation in SNS Linac 873
 
  • A.V. Aleksandrov, W. Blokland, Y. Liu, C.D. Long, A.P. Zhukov
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.
Uncontrolled beam loss is the major concern in operation of a high intensity hadron linac. A low density cloud of particles with large oscillation amplitudes, so called halo, can form around the dense regular beam core. This halo can be direct or indirect cause of beam loss. There is an experimental evidence of halo growing in SNS linac and limiting further reduction of beam loss. A set of tools is being developed for detecting of the halo and investigating its origin and dynamics. The set includes high resolution emittance measurements in the injector, laser based emittance measurements at 1 GeV, and high resolution profile measurements along the linac. We will present our experience with useful measurement techniques and data analysis algorithms as well as current understanding of the halo dynamics in SNS linac.
 
 
THPB014 Lattice Design and Beam Dynamics Studies for Project X 876
 
  • N. Solyak, J.-P. Carneiro, V.A. Lebedev, J.-F. Ostiguy, A. Saini
    Fermilab, Batavia, USA
 
  Fermilab is developing Project-X, a high intensity superconducting H machine for high energy physics experiments. The first stage is 1 mA average, 3 GeV linac operating in CW mode. Its front-end comprises a LEBT section with magnetic focusing and pre-chopping, a 162.5 MHz RFQ and ~10 m long MEBT section which includes a high bandwidth, bunch-by-bunch capable chopper. The latter extracts, out of a nominal 5 mA peak 162.5 MHz train, and arbitrary bunch structure able to meet the requirements of different experiments. Acceleration from 2.1 MeV to 3 GeV is accomplished through five families of SRF cavities operating at three frequencies: Half-wave resonators (162.5 MHz), spoke cavities (two families at 325 MHz) and elliptical cavities (two families at 650 MHz). In this contribution, we present the status of the CW linac lattice design and results from recent beam physics studies.  
 
THPB015 Performance of Ferrite Vector Modulators in the LLRF system of the Fermilab HINS 6-Cavity Test 879
 
  • P. Varghese, B.W. Barnes, B. Chase, E. Cullerton, C.C. Tan
    Fermilab, Batavia, USA
 
  The High Intensity Neutrino Source (HINS) 6-cavity test is a part of the Fermilab HINS Linac R&D program for a low energy, high intensity proton/H linear accelerator. One of the objectives of the 6-cavity test is to demonstrate the use of high power RF Ferrite Vector Modulators(FVM) for independent control of multiple cavities driven by a single klystron. The beamline includes an RFQ and six cavities. The LLRF system provides a primary feedback loop around the RFQ and the distribution of the regulated klystron output is controlled by secondary learning feed-forward loops on the FVMs for each of the six cavities. The feed-forward loops provide pulse to pulse correction to the current waveform profiles of the FVM power supplies to compensate for beam-loading and other disturbances. The learning feed-forward loops are shown to successfully control the amplitude and phase settings for the cavities well within the 1 % and 1 degree requirements specified for the system.  
 
THPB016 Concept: Low Energy, Low Intensity NF from ProjectX 882
 
  • M. Popovic
    Fermilab, Batavia, USA
 
  This note describes the concept of a Low Luminosity Low Energy Neutrino Factory (L3ENF) using a Project X pulsed, or CW, Linac at 8GeV. By collecting pis and mus with energy ~1 GeV, and accelerating them to 10 GeV, it is possible to store ~1020 mus per year. Most of the concepts suggested here can be tested using the Booster beam, Recycler, Antiproton Target Station, the Main Injector and the Tevatron. Once the VLENF Muon Storage Ring is built, components needed for L3ENF could be used in experiments before Project X completion.  
 
THPB017 A Concept: 8GeV CW Linac, Staged Approach 885
 
  • M. Popovic, J.-F. Ostiguy
    Fermilab, Batavia, USA
 
  This note describes a concept of CW Proton Linac on the Fermilab site. With exception of RFQ the linac is based on superconducting technology. Based on the output, energy is segmented in three parts, 1GeV, 3GeV and 8GeV. It is located near existing Fermilab Proton Source with the intention that each section of the linac can be used as soon as it is commissioned. The whole design is based on the designs suggested for the Proton Driver and ProjectX. The suggested site and linac segmentation allows for the construction to start immediately. Additional benefits come from the fact that the present linac (the oldest machine in Fermilab complex) is replaced and existing Proton Source’s functionality is preserved for the future.  
 
THPB020 Annular-ring Coupled Structure for the Energy Upgrade of the J-PARC Linac 888
 
  • H. Ao, H. Asano, N. Ouchi, J. Tamura
    JAEA/J-PARC, Tokai-mura, Japan
  • F. Naito, K. Takata
    KEK, Ibaraki, Japan
 
  The linac of Japan Proton Accelerator Research Complex (J-PARC), which is an injector to the synchrotron, comprises a 3-MeV RFQ, 50-MeV DTLs and the 181-MeV Separated-type DTLs. In order to increase the beam power of the synchrotron, the task of the 400-MeV energy upgrade of the linac started from March 2009. The tanks of the Annular-ring Coupled Structure (ACS) linac, RF sources, beam monitors and utilities are in production. Although some peripheral components of the ACS linac are prepared previously, the all ACS tanks will be installed and conditioned for 4 months from July 2013. Beam commissioning of the 400-MeV linac is scheduled to begin in October and expected to finish at the end of November 2013. In this paper, we present the current status of the energy upgrade and some R&D results for new equipment for ACS linac.  
 
THPB021 Recovery Efforts from the Tohoku Earthquake and Energy Upgrade Preparation of the Beam Transport from the J-PARC Linac to the 3-GeV Synchrotron 891
 
  • J. Tamura, H. Ao, H. Asano, T. Morishita, N. Ouchi
    JAEA/J-PARC, Tokai-mura, Japan
  • Y. Sawabe
    MELCO SC, Tsukuba, Japan
 
  In 2013, the beam energy of the Japan Proton Accelerator Research Complex (J-PARC) linac is going to be increased from 181-MeV to 400-MeV by adding the annular-ring coupled structure (ACS) at the downstream of the 191-MeV drift tube linac. To install and operate all the ACS cavities in only five months of the energy upgrade shutdown in 2013, we decided to replace and upgrade all the related component of the beam line (cables, magnet power supplies and vacuum control systems) for the 400-MeV operation, in the period of the recovery from the Tohoku Earthquake which caused not negligible damage to the J-PARC accelerator facilities. The present beam line is operated by using some part of the 400-MeV componets. In this paper, the recovery of the beam transport, the present status and the future tasks of the beam energy upgrade will be presented.  
 
THPB022 Beam Phase Measurement for PEFP Linear Accelerator 894
 
  • H.S. Kim, Y.-S. Cho, J.-H. Jang, H.-J. Kwon, J.Y. Ryu, K.T. Seol, Y.-G. Song
    KAERI, Daejon, Republic of Korea
 
  Funding: Works supported by the Ministry of Education, Science and Technology of Korean Government.
According to the commissioning plan of the PEFP proton linac, an accurate measurement of beam phase is essential, especially for setting up the RF operating parameters of DTL. Beam position monitors (BPMs) installed between DTL tanks can provide information about the beam phase as well as about the beam transverse position. By using a BPM as a beam phase monitor, beam phase can be measured without additional devices on the linac or the beam line. The signals from 4 electrodes in the BPM can be summed by using a 4-way RF combiner, by which the effect of the transverse beam offset on the phase measurement can be eliminated. The combined BPM signal (350 MHz) is mixed with LO signal (300 MHz) and down-converted to IF signal (50 MHz), then fed into the signal processing unit, where the phase information is extracted by using IQ demodulation method with a sampling frequency of 40 MHz. In this paper, the beam phase measurement system and signal processing scheme will be presented.
 
 
THPB023 Linac Construction for China Spallation Neutron Source 897
 
  • S. Fu, J. Li, H.C. Liu, H.F. Ouyang, X. Yin
    IHEP, Beijing, People's Republic of China
 
  Construction of China Spallation Neutron Source(CSNS) has been launched in September 2011. CSNS accelerator will provide 100kW proton beam on a target at beam energy of 1.6GeV. It consists of an 80MeV H linac and 1.6GeV rapid cycling synchrotron. Based on the prototyping experience, CSNS linac, including the front end and four DTL tanks, has finalized the design and started procurement. In this paper, we will first present an outline of the CSNS accelerator in its design and construction plan. Then the major prototyping results of the linac will be presented. Finally the linac construction progress in recent will be updated.  
 
THPB024 Main Linac Physics Design Study of the C-ADS Project 900
 
  • F. Yan, Z. Li, C. Meng, J.Y. Tang
    IHEP, Beijing, People's Republic of China
 
  Funding: The pilot special funds of Chinese Academy of Science
The Chinese ADS project is proposed to build a 1000MW Accelerator Driven sub-critical System before 2032. The accelerator will be operating on CW mode with 10mA average current and the final energy is 1.5GeV. The whole linac are composed of two major sections: the Injector section and the main linac section. There are two different schemes for the Injector section. InjectorI is basing on 325MHz RFQ and superconducting spoke cavities and Injector II is basing on 162.5MHz RFQ and superconducting HWR cavities. The main linac design will be different for different Injector choice. If Injector II scheme is adopted, the main linac bunch current will be doubled. In this paper we studied the main linac design basing on InjectorII scheme. The design principles and the priliminary design results is presented.
 
 
THPB025 325 MHz CW Room Temperature High Power Bunching Cavity for the China ADS MEBT1 903
 
  • S. Pei, X. Li, H.F. Ouyang, J.R. Zhang
    IHEP, Beijing, People's Republic of China
 
  Two room temperature high power bunching cavities are required to be located in the ADS MEBT1 section. Double re–entrant nose cone geometry has been adopted as the type of the bunching cavity for its simplicity, higher shunt impedance and lower risk of multipacting. SUPERFISH is used to optimize the internal dimensions of the bunching cavity, then the RF–thermal–structural–RF coupled analysis were carried out in ANSYS to obtain the preliminary mechanical design, the layout of the cooling channels is optimized to suppress the frequency shift as much as possible. The cavity was specially designed to have the capability to withstand the 1 atm air pressure effect. In addition, the main dimensions of the coupler and tuner are also estimated.
*peisl@ihep.ac.cn
 
 
THPB026 The Beam Commissioning Plan of Injector II in C-ADS 906
 
  • Z.J. Wang, Y. He, H. Jia, C. Li, S.H. Liu, W. Wu, X.B. Xu, B. Zhang, H.W. Zhao
    IMP, Lanzhou, People's Republic of China
 
  The design work of the Injector II, which is 10 MeV proton linac, in C-ADS project is being finished and some key elements are being fabricated. Now it is necessary to definite the operation mode of beam commissioning, including the selection of the beam current, pulse length and repetition frequency. Also the beam commissions plan should be specified. The beam commissions procedures is simulated with t-mode code GPT. In this paper, the general beam commissioning plan of Injector II in CIADS and simulation results of commissions procedures are presented.  
 
THPB027 Progress of one of 10 MeV superconducting proton linear Injectors for C-ADS 909
 
  • Y. He, J. Meng, A. Shi, Z.J. Wang, J.X. Wu, W. Wu, H.S. Xu, Z. Xu, B. Zhang, J.H. Zhang, S.H. Zhang, Z.M. Zhang, H.W. Zhao, Z.Z. Zhou
    IMP, Lanzhou, People's Republic of China
  • D. Li
    LBNL, Berkeley, California, USA
 
  A 10 MeV superconducting proton linac is being design and constructing at Institute of Modern Physics (IMP) of Chinese Academy of Sciences (CAS). This proton linac is one of two injectors for Chinese ADS project. It is to validate one of concepts for C-ADS front end, to demonstrate the low beta acceleration, to minimize the risk of key technoledges within the Reference Design. It consists of a 2.1 MeV RFQ and two cryomodules hosting 8 HWR cavities. The basic frequecy is 162.5 MHz. The physical design of linac and the progess of prototypes for solid state amplifiers, superconducting solenoids, supercondecting HWRs, ion source, and RFQ are presented in the paper.  
 
THPB028 The ESS Low Energy Beam Transport Line Design 912
 
  • L. Neri, L. Calabretta, A.C. Caruso, L. Celona, S. Gammino, A. Longhitano, D. Mascali
    INFN/LNS, Catania, Italy
  • B. Cheymol, A. Ponton
    ESS, Lund, Sweden
 
  The linear accelerator of the European Spallation Source (ESS) will deliver proton beams of 50 mA and 2.5 GeV onto the 5 MW neutron production target. The Proton Source for ESS (PS-ESS) [1] is based on the experience of TRIPS and VIS developed at LNS Catania [2,3]. A two solenoid Low Energy Beam Transport (LEBT) is foreseen to match the beam into the first acceleration stage, the Radio-Frequency Quadrupole (RFQ) [4]. Beam production means also detailed characterization of produced beam, with this scope the LEBT houses many instrumentation devices and use different techniques that will be described in this work. The LEBT will be also equipped with an electrostatic chopper in order to remove the unwanted part of the beam pulse during the natural rise and fall times of the ion source. Beam dynamics calculations of the LEBT have been carried out considering also the Space Charge Compensation (SCC) produced by the interaction of the beam with the residual gas, and its effect on beam transport and chopping. Particular emphasis has been put on the evaluation of the beam transient behavior, due to the chopping process, at the entrance of the RFQ, results of the study are presented in this paper.  
 
THPB029 The ESS RFQ Beam Dynamics Design 915
 
  • A. Ponton
    ESS, Lund, Sweden
 
  to be added  
 
THPB030 DTL Design for ESS 918
 
  • M. Comunian, F. Grespan, A. Pisent
    INFN/LNL, Legnaro (PD), Italy
  • R. De Prisco
    Lund University, Lund, Sweden
  • M. Eshraqi
    ESS, Lund, Sweden
  • P. Mereu
    INFN-Torino, Torino, Italy
 
  In the present design of the European Spallation Source (ESS) accelerator, the Drift Tube Linac (DTL) will accelerate a proton beam of 50 mA pulse peak current from 3 to 80 MeV. It is designed to operate at 352.2 MHz, with a duty cycle of 4% (3 ms pulse length, 14 Hz repetition period). Permanent magnet quadrupoles (PMQs) are used as focusing elements in a FODO lattice scheme, which leaves space for steerers and diagnostics . In this paper beam dynamics studies and preliminary RF design are shown, including constraints in terms of quadrupole dimensions, total length, field stability, RF power, peak electric field.  
 
THPB031 Status Report on the French High-intensity Proton Injector Project at SACLAY (IPHI) 921
 
  • B. Pottin, M. Desmons, A. France, R. Gobin, O. Piquet
    CEA/DSM/IRFU, France
 
  The construction of IPHI (High Power Proton Accelerator) is in its final step of installation. The high intensity light ion source (SILHI) has been built first to produce regularly CW high intensity (over 100 mA) proton beams. The low energy front end of IPHI is based on a 352 MHz, 6 m long Radiofrequency Quadrupole (RFQ) cavity. The RFQ will accelerate beam up to 100 mA with energy up to 3 MeV. A diagnostics line has been designed to measure all the main characteristics of the beam at the RFQ output. In this paper we will present the status for the main components of the injector, in particularly the RFQ fabrication and the RF power facilities.  
 
THPB032 Beam Dynamics Design Aspects for a Proposed 800 MeV H ISIS Linac 924
 
  • D.C. Plostinar, C.R. Prior, G.H. Rees
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
 
  Several schemes have been proposed to upgrade the ISIS Spallation Neutron Source at Rutherford Appleton Laboratory (RAL). One scenario is to develop a new 800 MeV, H linac and a ~3 GeV synchrotron, opening the possibility of achieving several MW of beam power. In this paper the design of the 800 MeV linac is outlined with an emphasis on the beam dynamics design philosophy. The linac consists of a 3 MeV Front End similar to the one now under construction at RAL (the Front End Test Stand -FETS). Above 3 MeV, a 324 MHz DTL will be used to accelerate the beam up to ~75 MeV. At this stage a novel collimation system will be added to remove the halo and the far off-momentum particles. To achieve the final energy, a 648 MHz superconducting linac will be employed using three families of elliptical cavities with transition energies at ~196 MeV and ~412 MeV.  
 
THPB034 Status of the FAIR 70 MeV Proton Linac 927
 
  • L. Groening, W.A. Barth, R. Berezov, G. Clemente, P. Forck, R. Hollinger, A. Krämer, C. Mühle, J. Pfister, G. Schreiber, J. Trüller, W. Vinzenz, C. Will
    GSI, Darmstadt, Germany
  • N. Chauvin, O. Delferrière, O. Tuske
    CEA/IRFU, Gif-sur-Yvette, France
  • B. Koubek, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede
    IAP, Frankfurt am Main, Germany
  • B. Launé, J. Lesrel
    IPN, Orsay, France
  • C.S. Simon
    CEA/DSM/IRFU, France
 
  To provide the primary proton beam for the FAIR anti-proton research program, a 70 MeV, 70 mA linac is currently under design & construction at GSI. The nc machine comprises an ECR source, a 3 MeV RFQ, and a DTL based on CH-cavities. Up to 36 MeV pairs of rf-coupled cavities (CCH) are used. A prototype cavity has been built and is prepared for high power rf-testing. An overview of the status as well as on the perspectives of the project is given.  
 
FR2A01 Recovery of the J-PARC Linac from the Earthquake 1069
 
  • K. Hasegawa
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
 
  Following the amazingly quick recovery from the disastrous earthquake in March 2011, and in the interests of promoting robust designs of linacs, it would be interesting to learn what the J-PARC team reckons are the key features of accelerator design and construction that lead to strong and reliable hardware.  
slides icon Slides FR2A01 [3.928 MB]