04 Hadron Accelerators
A15 High Intensity Accelerators
Paper Title Page
MOXBA01 J-PARC Beam Commissioning Progress 6
 
  • H. Hotchi
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  
  The J-PARC is a multi-purpose proton accelerator facility amiming at MW-class output beam power, consisting of a 400 MeV H− linac, a 3-GeV RCS, a 50-GeV MR (Main Ring) and three experimental facilities, the MLF (materials and life science experimental facility), the HD (hadron experimental hall) and the NU (neutrino beam line). The J-PARC beam commissioning started in November 2006 from the linac to the downstream facilities. The current output beam power from the RCS to the MLF users is 210 kW, and the MR delivers 145 kW beam to the NU by fast extraction and a few kW beam to the HD by slow extraction. In this talk, we present a current status of the J-PARC beam commissioning, in which a recent progress in the course of the RCS beam power ramp-up scenario will be described in more detail. This talk will focus on the issues (including beam dynamics), challenges, solutions, and lessons learned during the commissioning and user operation of J-PARC and future plans.  
slides icon Slides MOXBA01 [2.615 MB]  
 
TUXA01 Status and Challenges of the China Spallation Neutron Source 889
 
  • S. Fu, H. Chen, Y.W. Chen, Y.L. Chi, H. Dong, L. Dong, S.X. Fang, K.X. Huang, W. Kang, J. Li, L. Ma, H.F. Ouyang, H. Qu, H. Sun, J. Tang, C.H. Wang, Q.B. Wang, S. Wang, T.G. Xu, Z.X. Xu, X. Yin, C. Zhang, J. Zhang
    IHEP Beijing, Beijing, People's Republic of China
  
  The accelerator complex of China Spallation Neutron Source (CSNS) mainly consists of an H− linac of 80 MeV and a rapid-cycling synchrotron of 1.6 GeV. It operates at 25 Hz repetition rate with an initial proton beam power of 100 kW and is upgradeable to 500kW. The project will start construction in the middle of 2011 with a construction period of 6.5 years. The CSNS accelerator is the first large-scale, high-power accelerator project to be constructed in China and thus we are facing a lot of challenges. This paper presents the current status of CSNS project and summarizes the technology development during the past several years.  
slides icon Slides TUXA01 [3.444 MB]  
 
WEOBA01 ARIEL: TRIUMF’s Advanced Rare IsotopE Laboratory 1917
 
  • L. Merminga, F. Ames, R.A. Baartman, C.D. Beard, P.G. Bricault, I.V. Bylinskii, Y.-C. Chao, R.J. Dawson, D. Kaltchev, S.R. Koscielniak, R.E. Laxdal, F. Mammarella, M. Marchetto, G. Minor, A.K. Mitra, Y.-N. Rao, M. Trinczek, A. Trudel, V.A. Verzilov, V. Zvyagintsev
    TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
  
  TRIUMF has recently embarked on the construction of ARIEL, the Advanced Rare Isotope Laboratory, with the goal to significantly expand the Rare Isotope Beam (RIB) program for Nuclear Physics and Astrophysics, Nuclear Medicine and Materials Science. ARIEL will use proton-induced spallation and electron-driven photo-fission of ISOL targets for the production of short-lived rare isotopes that are delivered to experiments at the existing ISAC facility. Combined with ISAC, ARIEL will support delivery of three simultaneous RIBs, up to two accelerated, new beam species and increased beam development capabilities. The ARIEL complex comprises a new SRF 50 MeV 10 mA CW electron linac photo-fission driver and beamline to the targets; one new proton beamline from the 500 MeV cyclotron to the targets; two new high power target stations; mass separators and ion transport to the ISAC-I and ISAC-II accelerator complexes; a new building to house the target stations, remote handling, chemistry labs, front-end and a tunnel for the proton and electron beamlines. This report will include overview of ARIEL, its technical challenges and solutions identified, and status of design activities.  
slides icon Slides WEOBA01 [3.676 MB]  
 
WEPC041 Conceptual Design of a New 800 MeV H− Linac for ISIS Megawatt Developments 2100
 
  • 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. It 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. Alternative designs are also being investigated.  
 
WEPS068 Progress towards an RFQ-based Front End for LANSCE 2658
 
  • R.W. Garnett, S.S. Kurennoy, J.F. O'Hara, L. Rybarcyk
    LANL, Los Alamos, New Mexico, USA
  • A. Schempp
    IAP, Frankfurt am Main, Germany
  
  Funding: This work is supported by the U. S. Department of Energy Contract DE-AC52-06NA25396.
The LANSCE linear accelerator at Los Alamos National Laboratory provides H− and H+ beams to several user facilities that support Isotope Production, NNSA Stockpile Stewardship, and Basic Energy Science programs. These beams are initially accelerated to 750 keV using Cockcroft-Walton (CW) based injectors that have been in operation for over 37 years. They have failure modes which can result in prolonged operational downtime due to the unavailability of replacement parts. To reduce long-term operational risks and to realize future beam performance goals in support of the Materials Test Station (MTS) and the Matter-Radiation Interactions in Extremes (MaRIE) Facility, plans are underway to develop a Radio-Frequency Quadrupole (RFQ) based front end as a modern injector replacement for the existing CW injectors. Our progress to date will be discussed. 		 
 
WEPS090 The Myrrha Linear Accelerator 2718
 
  • D. Vandeplassche
    SCK-CEN, Mol, Belgium
  • J.-L. Biarrotte
    IPN, Orsay, France
  • H. Klein, H. Podlech
    IAP, Frankfurt am Main, Germany
  
  Funding: European Atomic Energy Community's (EURATOM) Seventh Framework Programme FP7/2007-2011, grant agreement no. 269565 (MAX project)
Accelerator Driven Systems (ADS) are promising tools for the efficient transmutation of nuclear waste products in dedicated industrial installations, called transmuters. The Myrrha project at Mol, Belgium, placed itself on the path towards these applications with a multipurpose and versatile system based on a liquid PbBi (LBE) cooled fast reactor (80 MWth) which may be operated in both critical and subcritical modes. In the latter case the core is fed by spallation neutrons obtained from a 600 MeV proton beam hitting the LBE coolant/target. The accelerator providing this beam is a high intensity CW superconducting linac which is laid out for the highest achievable reliability. The combination of a parallel redundant and of a fault tolerant scheme should allow obtaining an MTBF value in excess of 250 hours that is required for optimal integrity and successful operation of the ADS. Myrrha is expected to be operational in 2023. The forthcoming 4-year period is fully dedicated to R&D activities, and in the field of the accelerator they are strongly focused on the reliability aspects and on the proper shaping of the beam trip spectrum. 		 
 
WEPS092 High Energy Beam Line Design of the 600MeV, 4 mA Proton Linac for the MYRRHA Facility 2721
 
  • H. Saugnac
    IPN, Orsay, France
  
  The general goal of the CDT project is to design a FAst Spectrum Transmutation Experimental Facility (FASTEF) able to demonstrate efficient transmutation and associated technology through a system working in subcritical and/or critical mode. A superconducting LINAC, part of the MYRRHA facility, will produce a 600 MeV, 4 mA proton beam and transport it to the spalation target located inside the reactor core. On this paper we focus on the final beam line design and describe optic simulations, beam instrumentation, integration inside the reactor building, mechanical and vacuum aspects as well as a preliminary design of the 2.4 MW beam dump located at the end of the accelerator tunnel.  
 
WEPS094 Dynamic Vacuum Stability in SIS100 2724
 
  • P. Puppel, U. Ratzinger
    IAP, Frankfurt am Main, Germany
  • P.J. Spiller
    GSI, Darmstadt, Germany
  
  SIS100 is the main synchrotron of the FAIR project. It is designed to accelerate high intensity intermediate charge state uranium beams from 200 MeV/u up to 2.7 GeV/u. Intermediate charge state heavy ions are exposed to a high probability of charge exchange due to collisions with residual gas molecules. Since the charge exchange process changes the magnetic rigidity, the involved ions are lost behind dispersive elements, and an energy-dependent gas desorption takes place. The StrahlSim code has been used to predict the stability of the residual gas pressure in SIS100 under beam loss driven dynamic conditions. The results show, that a stable operation at highest U28+ intensities is possible, under the constraint that the vacuum chambers of the ion catcher system are cold enough to pump hydrogen. Furthermore, in order to determine the load to the cryogenic system, the average beam energy deposition onto the ion catcher system has been calculated.  
 
WEPS095 Status of J-PARC Accelerator Facilities after the Great East Japan Earthquake 2727
 
  • K. Hasegawa, M. Kinsho, H. Oguri
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • T. Koseki
    KEK, Tokai, Ibaraki, Japan
  
  J-PARC was heavily affected by the March 11 Great East Japan Earthquake. When the earthquake struck, we had a beam study operation of the linac and the machine immediately stopped. Fortunately, we had no effects of tsunami that happened nearby and no one was injured. We can see subsidence at many places; about 1.5m over the wide area at the entrance of the linac building, about 50cm over the area of 1m x 10m at the main ring building, etc. Underground water is coming into the linac and the main ring tunnels. The water level at the linac reached a depth of 10 cm, but pumping with a diesel generator successfully saved from further flooding. At the RCS, the circulating road went wavy and the yard area for electricity and water devices was heavily distorted. Therefore, a high voltage power is not available on the date of abstract submission. We are investigating damages of each facility and also we are trying to estimate the beam restoration. The current status of the J-PARC accelerator facilities after the earthquake will be presented.  
 
WEPS096 Injection Energy Recovery of J-PARC RCS 2730
 
  • N. Hayashi, H. Hotchi, J. Kamiya, P.K. Saha, T. Takayanagi, K. Yamamoto, M. Yamamoto, Y. Yamazaki
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  
  The J-PARC RCS is a high beam power Rapid-Cycling Synchrotron (RCS). The original designed injection energy is 400MeV, although presently it is 181MeV, and its beam power is limited to 0.6MW. Works to recover the Linac energy are ongoing and injection magnets power supplies upgrade are required in the RCS. In order to achieve 1MW designed beam power, new instrumentation is also planned simultaneously. Activities related injection energy recovery in the J-PARC RCS is presented.  
 
WEPS097 Performance of Multi-harmonic RF Feedforward System for Beam Loading Compensation in the J-PARC RCS 2733
 
  • F. Tamura, M. Nomura, A. Schnase, T. Shimada, M. Yamamoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • K. Hara, C. Ohmori, M. Toda, M. Yoshii
    KEK/JAEA, Ibaraki-Ken, Japan
  • K. Hasegawa
    KEK, Tokai, Ibaraki, Japan
  
  The beam loading compensation is a key part for acceleration of high intensity proton beams in the J-PARC RCS. In the wide-band MA-loaded RF cavity, the wake voltage consists of not only the accelerating harmonic component but also the higher harmonics. The higher harmonic components cause the RF bucket distortion. We employ the RF feedforward method to compensate the multi-harmonic beam loading. The full-digital feedforward system is developed, which compensates the first three harmonic components of the beam loading. We present the results of the beam test with a high intensity proton beam (2.5·1013 ppp). The impedance seen by the beam is greatly reduced, the impedance of the fundamental accelerating harmonic is reduced to less than 25 ohms in a full accelerating cycle, while the shunt resistance of the cavity is in the order of 800 ohms. The performance of the feedforward system is promising for achievement of the design beam power, 1 MW, in the future.  
 
WEPS098 Combined Momentum Collimation Method in High-intensity Rapid Cycling Proton Synchrotrons 2736
 
  • J.F. Chen, J. Tang, Y. Zou
    IHEP Beijing, Beijing, People's Republic of China
  
  A new momentum collimation method – so-called combined momentum collimation method in high-intensity synchrotrons is proposed and studied here, which makes use two-stage collimation in both the longitudinal and the transverse phase planes. The primary collimator is placed at a high-dispersion location of an arc, and the longitudinal and transverse secondary collimators are in the same arc and in the down-stream dispersion-free long straight section, respectively. The particles with positive momentum deviations will be scattered and degraded by a carbon scraper and then cleaned mainly by the transverse collimators, whereas the particles with negative momentum deviations will be scattered by a tantalum scraper and mainly cleaned by the longitudinal secondary collimators in the successive turns. Numerical simulation results using TURTLE and ORBIT codes show that this method gives high collimation efficiency for medium-energy synchrotrons. The studies have also shown two interesting effects: one is that the momentum collimation is strongly dependent on the transverse beam correlation; the other is that the material for the primary collimator plays an important role in the method.
This work was supported by the National Natural Science Foundation of China (10975150, 10775153), the CAS Knowledge Innovation Program-“CSNS R&D Studies”. 		 
 
WEPS099 Physics Design of CSNS RCS Injection and Extraction System 2739
 
  • J. Qiu, N. Huang, J. Tang, S. Wang
    IHEP Beijing, Beijing, People's Republic of China
  
  In this paper, the injection and extraction system design for CSNS RCS are discussed. The injection system is designed to place all the injection devices in one uninterrupted long drift in one of the four dispersion free straight sections. Painting bumper magnets are used for both horizontal and vertical phase space painting. The beam extraction process from the CSNS RCS is a single turn two step process, requiring a group of kickers and a Lambertson septum magnet.  
 
WEPS100 Status of 100-MeV Proton Linac Development for PEFP 2742
 
  • Y.-S. Cho, S. Cha, I.-S. Hong, J.-H. Jang, D.I. Kim, H.S. Kim, H.-J. Kwon, K. Min, B.-S. Park, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun
    KAERI, Daejon, Republic of Korea
  • J.S. Hong
    KAPRA, Cheorwon, Republic of Korea
  
  Funding: This wok was supported through the Proton Engineering Frontier Project by the Ministry of Education, Science and Technology of Korea.
The Proton Engineering Frontier Project (PEFP) is developing a 100-MeV high-duty-factor proton linac, which consists of a 50-keV microwave ion source, a 3-MeV radio frequency quadrupole, a 100-MeV drift tube linac, a 20-MeV beam transport line, and a 100-MeV beam transport line. It will supply proton beams of 20-MeV and 100-MeV with peak current of 20 mA to users for proton beam applications. The beam duty factor will be 24% and 8% respectively. The 20-MeV front-end accelerator has been installed and operated at the KAERI Daejeon test stand for user service, and the rest part of the accelerator has been fabricated and will be installed at the new site of Gyeongju City in 2011. The detailed status of the 100-MeV proton linac will be presented. 		 
 
WEPS101 Lattice Design of a RCS as Possible Alternative to the PS Booster Upgrade 2745
 
  • M. Fitterer, M. Benedikt, H. Burkhardt, C. Carli, R. Garoby, B. Goddard, K. Hanke, H.O. Schönauer
    CERN, Geneva, Switzerland
  • A.-S. Müller
    KIT, Karlsruhe, Germany
  
  In the framework of the LHC Injectors Upgrade (LIU) a new rapid cycling synchrotron as alternative to the PS Booster has been proposed. In this paper we present the lattice constraints and requirement as well as the current status of the RCS lattice design and beam dynamics studies.  
 
WEPS102 Latest News on the Beam Dynamics Design of SPL 2748
 
  • P.A. Posocco, M. Eshraqi, A.M. Lombardi
    CERN, Geneva, Switzerland
  
  SPL is a superconducting H− LINAC under study at CERN. The SPL is designed to accelerate the 160 MeV beam of LINAC4 to 5 GeV, and is composed of two fami¬lies of 704.4 MHz elliptical cavities with geometrical betas of 0.65 and 1.0. Two families of cryo-modules are considered: the low-beta cryo-module houses 3 low-beta cavities, whereas the high-beta one houses 8 cavities. The transverse focusing is performed with normal-conducting quadrupoles arranged in 2 different lattices: FD0 at lower and F0D0 at higher energies. The regular lattices are in-terrupted at the transition between low beta and high beta cryo-modules and for extracting medium energy beams at 1.4 and 2.5 GeV, where the change of the transverse lattice is performed. In this paper the latest beam dynamics studies will be presented together with the sensitivity of the SPL performance to RF errors, alignment tolerances and quadrupole high order components.  
 
WEPS103 Design of a Rapid Cycling Synchrotron for the Final Stage of Acceleration in a Common Proton Driver for a Neutrino Factory and a Spallation Neutron Source Based on Megawatt Upgrades to ISIS 2751
 
  • J. Pasternak
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • L.J. Jenner, J. Pasternak
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  
  Potential upgrades to the ISIS accelerators at RAL in the UK to provide proton beams in the few GeV and few MW range could be envisaged as the starting point for a proton driver shared between a short pulse spallation neutron source and the Neutrino Factory. The accelerator chain for the spallation neutron source, consisting of an 800 MeV H− linac and a 3.2 GeV rapid cycling synchrotron (RCS), is currently being designed and optimised. The design of the RCS for the final stage of acceleration, which would increase the final beam energy of the dedicated pulses to feed the Neutrino Factory pion production target is presented. The feasibility of the final bunch compression to the necessary nanosecond range is also discussed.  
 
WEPS104 Transverse Beam Dynamics for the ISIS Synchrotron with Higher Energy Injection 2754
 
  • B.G. Pine, C.M. Warsop
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  
  ISIS is the spallation neutron source at the Rutherford Appleton Laboratory in the UK. Operation centres on an 800 MeV rapid cycling synchrotron, which provides 3·1013 protons per pulse at 50 Hz, corresponding to a beam power of 200 kW. Studies are underway to increase the energy of the ISIS linac from 70 to 180 MeV. This would reduce space charge in the synchrotron, and enable a larger current to be accumulated, possibly up to 0.5 MW. As part of the study, transverse beam dynamics have been re-examined on ISIS, building up models from incoherent space charge tune shift, through smooth focusing models with space charge to 2D alternating gradient lattice simulations. These later simulations, using the in-house space charge code Set, include harmonic perturbations to the focusing lattice, closed orbits and images. A clearer picture of the dynamics is emerging, where there may be important constraints on the highest intensities, including half integer resonance, image induced structure resonances and transverse instabilities.  
 
WEPS105 A Common Proton Driver for a Neutrino Factory and a Spallation Neutron Source Based on Megawatt Upgrades to ISIS 2757
 
  • J.W.G. Thomason
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • J. Pasternak
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  
  The Rutherford Appleton Laboratory (RAL) is home to ISIS, the world’s most productive spallation neutron source. Potential upgrades of the ISIS accelerators to provide beam powers of 2 – 5 MW in the few GeV energy range could be envisaged as the starting point for a proton driver shared between a short pulse spallation neutron source and the Neutrino Factory. The concept of sharing a proton driver between other facilities and the Neutrino Factory is an attractive, cost-effective solution which is already being studied in site-specific cases at CERN and FNAL. Although in the RAL case the requirements for the Neutrino Factory baseline proton energy and time structure are different from those for a spallation neutron source, an additional RCS or FFAG booster bridging the gap in proton energy and performing appropriate bunch compression seems feasible.  
 
WEPS106 Status of Injection Upgrade Studies for the ISIS Synchrotron 2760
 
  • C.M. Warsop, D.J. Adams, D.J.S. Findlay, I.S.K. Gardner, S.J.S. Jago, B. Jones, R.J. Mathieson, S.J. Payne, B.G. Pine, A. Seville, H. V. Smith, J.W.G. Thomason, R.E. Williamson
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • J. Pasternak
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  • C.R. Prior, G.H. Rees
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  
  ISIS is the spallation neutron source at the Rutherford Appleton Laboratory in the UK. Operation centres on a high intensity proton accelerator, consisting of a 70 MeV linac and an 800 MeV rapid cycling synchrotron, which provides a beam power of 0.2 MW. Obsolescence issues are motivating plans to replace the ageing 70 MeV linac, and this paper summarises the status of studies looking at how a new, higher energy linac (~180 MeV) could be used to increase beam power in the existing synchrotron. Reduced space charge and optimized injection might allow beam powers in the 0.5 MW regime, thus providing a very cost effective upgrade. The key areas of study are: design of a practical injection straight and magnets; injection painting and dynamics; foil specifications; acceleration dynamics; transverse space charge; instabilities; RF beam loading; beam loss and activation; diagnostics and possible damping systems. Results from work on most of these topics suggest that beam powers of ~0.5 MW may well be possible, but a number of topics, particularly transverse stability, still look challenging. Conclusions so far are presented, as is progress on R&D on the main intensity limiting issues.  
 
WEPS107 Phase Space Coating in Synchrotrons: Some Applications* 2763
 
  • C.M. Bhat
    Fermilab, Batavia, USA
  
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy
Phase-space painting to produce very high intensity beam in synchrotrons is one of the widely studied topics in accelerator physics. A remarkable example of this is multi-turn beam injection by transverse phase-space painting in spallation sources. Use of barrier buckets at synchrotron storage rings has paved way for further advancements in this field. The Fermilab Recycler, antiproton storage ring, has been augmented with multipurpose broad-band barrier rf systems. Recently we have developed a longitudinal phase-space coating technique over already e-cooled high intensity low longitudinal antiproton beam and demonstrated with beam experiments. This method is extended to map the incoherent synchrotron tune of beam particles in a barrier bucket. Here I review various phase-space painting techniques being used in particle accelerators including some new schemes developed using barrier rf systems and possible new applications. 		 
 
FRYBA01 The European Spallation Source 3789
 
  • S. Peggs
    ESS, Lund, Sweden
  
  The principles of the design, and the technical and beam dynamics challenges of the ESS are presented, as well as possible future upgrade options.  
slides icon Slides FRYBA01 [5.122 MB]