MO3A —  Invited Oral Presentations   (10-Sep-12   13:30—14:50)
Chair: M. Popovic, Fermilab, Batavia, USA
Paper Title Page
MO3A01 Development of H-mode Linacs for the FAIR Project 120
  • G. Clemente, W.A. Barth, L. Groening, S. Mickat, B. Schlitt, W. Vinzenz
    GSI, Darmstadt, Germany
  • R. M. Brodhage, M. Busch, F.D. Dziuba, H. Podlech, U. Ratzinger
    IAP, Frankfurt am Main, Germany
  H-mode cavities offer outstanding shunt impedances at low beam energies and enable the acceleration of intense ion beams. Crossed-bar H-cavities extend these properties to energies even beyond 100 MeV. Thus, the designs of the new injector linacs for FAIR, i.e. a 70 MeV, 70 mA proton driver for pbar-production and a cw intermediate mass, superconducting ion linac are based on these novel cavities. Several prototypes (normal & super-conducting) have been built and successfully tested. Moreover, designs for a replacement of the 80 MV Alvarez section of the GSI - Unilac will be discussed to improve the capabilities as the future FAIR heavy ion injector.  
slides icon Slides MO3A01 [2.741 MB]  
MO3A02 Commissioning of a New Injector for the RIKEN RI-Beam Factory 125
  • N. Sakamoto, M. Fujimaki, H. Hasebe, Y. Higurashi, O. Kamigaito, H. Okuno, K. Suda, T. Watanabe, K. Yamada
    RIKEN Nishina Center, Wako, Japan
  • R. Koyama
    SHI Accelerator Service Ltd., Tokyo, Japan
  A new injector for the RIKEN RI-Beam Factory (RIBF) has been fully commissioned since October 2011. The injector accelerates ions of m/q=6.8 up to 670 keV/u. In order to save the cost and space, a direct coupling scheme was adopted for rf coupling between the cavity and amplifier, based on an elaborate design with the Microwave Studio code. It has worked out very stably in these three months, making the uranium beam intensity higher by one order of magnitude. Moreover, it is now possible to operate the RIBF and GARIS facility for the super-heavy element synthesis independently.  
slides icon Slides MO3A02 [19.503 MB]  
MO3A03 FRANZ – Accelerator Test Bench and Neutron Source 130
  • O. Meusel, L.P. Chau, M. Heilmann, H. Podlech, U. Ratzinger, K. Volk, C. Wiesner
    IAP, Frankfurt am Main, Germany
  The challenge of existing and planned neutron sources is to provide highly brilliant ion beams with high reliability. The Frankfurt neutron source FRANZ is not only a neutron source but also a test bench for novel accelerator and diagnostic concepts for intense ion beams. The experiment consists of a compact linear accelerator test bench for the acceleration of an intense proton beam to 2 MeV producing the neutrons via the 7Li(p,n) reaction. The final beam intensity will be 200 mA, therefore the space charge and space charge compensation effects can be studied with high statistical relevance along the accelerator. The low energy beam transport LEBT is equipped with four solenoids matching the beam into the chopper system and into the RFQ-IH combination already under construction. The coupling of the RFQ accelerator stage and the IH drift tube cavity offers the possibility to use only one power amplifier as a driver for both of these resonators and reduces investment costs. The compact design of this low-β accelerator stage is optimized for high beam intensities to overcome the strong space charge forces expected in this accelerator test bench.  
MO3A04 Accelerator/Decelerator of Slow Neutrons 133
  • M. Kitaguchi
    Kyoto University, Research Reactor Institute, Osaka, Japan
  • Y. Arimoto, H.M. Shimizu
    KEK, Ibaraki, Japan
  • P.W. Geltenbort
    ILL, Grenoble, France
  • S. Imajo
    Kyoto University, Kyoto, Japan
  • Y. Iwashita
    Kyoto ICR, Uji, Kyoto, Japan
  • Y. Seki
    RIKEN Nishina Center, Wako, Japan
  • T. Yoshioka
    Kyushu University, Fukuoka, Japan
  Funding: Supported by the Quantum Beam Fundamentals Development Program MEXT, a Grant-in-Aid for Creative Scientific Research of MEXT Program No.19GS0210 and No.23244047, Yamada Science Foundation, and KEK.
An accelerator/decelerator for slow neutron beams has been demonstrated. The energy of a neutron can be increased or decreased by flipping the neutron spin (directly coupled to magnetic dipole moment) in magnetic field. This device is a combination of a gradient magnetic field and an RF magnetic field. Because the RF frequency for the spin flip is a function of the external magnetic field, only neutrons that are located in a specific magnetic field level will be spin-flipped at a given RF frequency. By changing the RF frequency, the energy change can be selected in the gradient magnetic field. The maximum field of the gradient magnet is 1 T, which corresponds to the energy change of 120 neV. The magnetic field linearly decreases to 0.2T within 25 cm. By putting this device on a beamline from a pulsed neutron source, neutron rebuncher is realized. The dense slow neutrons are important to suppress the systematic errors for the measurement of neutron electric dipole moment (nEDM). The combination of spallation neutron source and this neutron rebuncher is suitable to the measurement of nEDM. A review of current status of our plan for nEDM experiment at J-PARC will be also presented.
slides icon Slides MO3A04 [3.750 MB]