| Paper |
Title |
Page |
| TUPLS106 |
Pulsed Bending Magnet of the J-PARC MR
|
1747 |
| |
- K. Koseki, H. Kobayashi, H. Nakayama, K.O. Okamura, M.J. Shirakata, M. Tawada
KEK, Ibaraki
|
|
| |
Japan Proton Accelerator Research Complex (J-PARC) is under construction with a collaboration between Japan Atomic Energy Agency (JAEA) and High Energy Accelerator Research Organization (KEK). The J-PARC consists of a 180 MeV linac, a 3 GeV rapid-cycle synchrotron (RCS) and a 50 GeV synchrotron (MR). The bunch trains, which extracted from the RCS, is delivered both to the “Materials and Life Science Facility” and to the MR, two beam transport lines, 3-NBT and 3-50BT, are constructed. The switching of bunch trains is performed by a pulsed bending magnet. The field strength of 1.21 Tesla with rise and fall time of less than 40 msec is required. It was found that an effect induced by eddy current, which flows at thick end-plates, disturbs the flatness of the magnetic field. A simple compensation circuit has been adopted for a cure. A result from a field measurement, which shows a sufficient flatness, is presented.
|
|
| TUPLS010 |
New Beam Transport Line from LINAC to Photon Factory in KEK
|
1505 |
| |
- N. Iida, K. Furukawa, M. Ikeda, K. Kakihara, T. Kamitani, M. Kikuchi, Y. Kobayashi, T. Mitsuhashi, Y. Ogawa, M. Satoh, T. Suwada, M. Tawada, K. Yokoyama
KEK, Ibaraki
|
|
| |
The e+/e- injector LINAC in KEK usually injects into four rings which are Low Energy Ring (LER) of KEKB (3.5GeV/e+), High Energy Ring (HER) of KEKB(8.0GeV/e-), Photon Factory (PF)(2.5GeV/e-) and Advanced Ring for pulse x-rays (PF-AR)(3.0GeV/e-). While LINAC continuously injects into LER and HER alternately about every five minutes, both of the KEKB rings usually store almost full operating currents. Time for PF or PF-AR, which includes switching time, took about 20 minutes several times a day. During this, the storage currents in KEKB rings decreased, and the optimum points of luminosity tuning had been lost. It had taken more than two hours to recover the luminosity. It is so useful for KEKB to shorten the time for switch LINAC KEKB to/from PF or PF-AR. In summer of 2005, the transport line from LINAC to PF were renewed, in which a DC bending magnet only for PF line apportions electron beam from the end of LINAC to the new line. We succeeded to reduce the occupancy time for PF injection to about five minutes. In this paper design of the new PF beam transport line and the practical performance achieved according to the design are described.
|
|