IBIC2012 - List of Authors (Hanamura, K.)

Paper	Title	Page
MOPA26	Performance and Upgrade of BPMs at the J-PARC MR	107
	T. Toyama, Y. Hashimoto J-PARC, KEK & JAEA, Ibaraki-ken, Japan K. Hanamura Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan S. Hatakeyama JAEA/J-PARC, Tokai-mura, Japan M. Okada, M. Tejima KEK, Ibaraki, Japan
	Since recovery from the great earthquake 2011.3.11, proton beam, more than 10¹⁴ ppp, is accelerated up to 30 GeV at the J-PARC MR. The BPMs were originally designed with the external capacitors. The aim was to improve the position response in wider frequencies and to get an adequate output voltage at the design intensity, 4x10¹³ ppb. It was modified, however, not to have the capacitors. Therefore we have sufficient signal intensity from low intensity beams of the initial beam commissioning, but too large from the design intensity beam. The processing circuits (BPMC) have to accommodate those output signals from high intensity beams. We are adding the attenuator-LPFs just before the BPMC. This paper will describe these additional attenuator-LPFs. In connection with the MR collimator upgrade, some BPMs are re-allocated. This process is also reported.

TUPB78	Flying Wire Beam Profile Monitors at the J-PARC MR	527
	S. Igarashi, D.A. Arakawa, Y. Hashimoto, M. Tejima, T. Toyama KEK, Ibaraki, Japan K. Hanamura Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
	Transverse beam profiles have been measured using flying wire monitors at the main ring of the Japan Proton Accelerator Research Complex. The wire target should be thin and the wire scan has to be fast for the precise profile measurement. Otherwise the beam distribution would be disturbed and the measured profile would not be accurate. We use carbon fibers of 7 μm in diameter and the scan speed of 10 m/s. The wire is attached with an aluminum flame of 140 mm of the rotation radius and rotated with a DC servomotor. A potentiometer is attached to the wire flame and the angle readout is used for the feedback of the servomotor and the wire position measurement. The secondary particles from the beam-wire scattering are measured with a scintillation counter. Beam profiles are reconstructed by making the scatter plot of the scintillator signal and wire position. Both horizontal and vertical flying wire monitors have been used for the beam commissioning. We have successfully measured the beam profile of up to 1.2×10¹³ protons per bunch.

Paper

Title

Page

Performance and Upgrade of BPMs at the J-PARC MR

107

T. Toyama, Y. Hashimoto
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
K. Hanamura
Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
S. Hatakeyama
JAEA/J-PARC, Tokai-mura, Japan
M. Okada, M. Tejima
KEK, Ibaraki, Japan

Since recovery from the great earthquake 2011.3.11, proton beam, more than 10¹⁴ ppp, is accelerated up to 30 GeV at the J-PARC MR. The BPMs were originally designed with the external capacitors. The aim was to improve the position response in wider frequencies and to get an adequate output voltage at the design intensity, 4x10¹³ ppb. It was modified, however, not to have the capacitors. Therefore we have sufficient signal intensity from low intensity beams of the initial beam commissioning, but too large from the design intensity beam. The processing circuits (BPMC) have to accommodate those output signals from high intensity beams. We are adding the attenuator-LPFs just before the BPMC. This paper will describe these additional attenuator-LPFs. In connection with the MR collimator upgrade, some BPMs are re-allocated. This process is also reported.

TUPB78

Flying Wire Beam Profile Monitors at the J-PARC MR

527

S. Igarashi, D.A. Arakawa, Y. Hashimoto, M. Tejima, T. Toyama
KEK, Ibaraki, Japan
K. Hanamura
Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan

Transverse beam profiles have been measured using flying wire monitors at the main ring of the Japan Proton Accelerator Research Complex. The wire target should be thin and the wire scan has to be fast for the precise profile measurement. Otherwise the beam distribution would be disturbed and the measured profile would not be accurate. We use carbon fibers of 7 μm in diameter and the scan speed of 10 m/s. The wire is attached with an aluminum flame of 140 mm of the rotation radius and rotated with a DC servomotor. A potentiometer is attached to the wire flame and the angle readout is used for the feedback of the servomotor and the wire position measurement. The secondary particles from the beam-wire scattering are measured with a scintillation counter. Beam profiles are reconstructed by making the scatter plot of the scintillator signal and wire position. Both horizontal and vertical flying wire monitors have been used for the beam commissioning. We have successfully measured the beam profile of up to 1.2×10¹³ protons per bunch.