Abstracts Brochure - CERN

MOPCH119
MOPCH120
MOPCH121
26-Jun-06 16:00 - 18:00 MOPCH — Poster Session
Present Status of the Induction Synchrotron Experiment in the KEK PS
K. Takayama, D.A. Arakawa, Y. Arakida, T. Iwashita, T. Kono, E.
Nakamura, K.O. Otsuka, Y. Shimosaki, M.J. Shirakata, T. Sueno, K.
Torikai (KEK)
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A concept of the induction synchrotron,
which was proposed by Takayama and
Kishiro in 2000, has been demonstrated by
using the KEK PS since 2004. A proton bunch
trapped in the RF bucket was accelerated
with the induction acceleration devices from 500 MeV to 8 GeV*, which was energized with the newly developed
switching power supply. This form of the KEK PS is something like a hybrid synchrotron. In addition, the injected
proton bunch was confined by the step barrier-voltages at the injection energy of 500MeV**, which were generated
with the same induction acceleration device. Then a concept of the induction synchrotron that a proton bunch was
captured by the barrier bucket and accelerated with the induction voltage is to be fully demonstrated.
*K. Takayama et al. "Observation of the Acceleration of a Single Bunch by Using the Induction Device in the KEK
Proton Synchrotron", Phys. Rev. Lett., 94, 144801 (2005).**K. Torikai et al. "Acceleration and Confinement of a Proton
Bunch with the Induction Acceleration System in the KEK Proton Synchrotron", submitted to Phys. Rev. ST-AB
(2005), KEK-Preprint 2005-80 A, December 2005.
Ground Motion Study and the Related Effects on the J-PARC
S. Takeda, N. Yamamoto, M. Yoshioka (KEK) Y. Nakayama
(JPOWER)
The power spectrum density, coherence and
cross-spectrum density of the ground motion
in the J-PARC site are studied to get the
guideline of the beam control systems. J-
PARC consists of a 600 MeV linac, a 3 GeV Rapid-cycling synchrotron (RCS) and a 50 GeV synchrotron (MR). MR
provides a beam current of 15 micro-A with a period of 3 sec to either the nuclear physics experimental area or the
neutrino production target. MR is a very high beam power machine, so its optimum beam loss must be kept fewer
than 0.01% of an accelerated beam in order to decrease the radiation damage of accelerator components and to get
easy accessibilty to them. From the point of view of beam loss, we give some detailed discussion about the relation
between the MR operation and the ground motion using the observed data.
Ground Motion Measurement at J-PARC
In the next generation accelerator, construc-
Y. Nakayama, K. Tada (JPOWER) S. Takeda, M. Yoshioka (KEK) tion of the machine on the stable ground
is preferable for accelerator beam operation.
We have measured ground motion at the J-PARC site under construction, where the ground is very close to the Pacific
Ocean. In this paper, some of the observed results are shown, comparing the results of the previous observation at
some accelerator facilities and next generation accelerator candidate sites in Japan.