IPAC2014 - List of Authors (Toyama, T.)

Paper	Title	Page
THOAA03	Transverse Intra-bunch Feedback in the J-PARC MR	2786
SUSPSNE086	use link to see paper's listing under its alternate paper code
	K. Nakamura Kyoto University, Kyoto, Japan Y.H. Chin, T. Obina, M. Okada, M. Tobiyama KEK, Ibaraki, Japan T. Koseki, T. Toyama J-PARC, KEK & JAEA, Ibaraki-ken, Japan Y. Shobuda JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	We will report the development of a new broadband (bandwidth of around 100MHz) feedback system for suppression of intra-bunch oscillations and reduction of particle losses at the J-PARC Main Ring (MR). A new BPM has been designed based on the exponential coupler stripline type (the diameter of 134 mm and the length of 300 mm) and it is now under fabrication. In this BPM system, the frequency characteristics are corrected using the equalizer as bunch signals are differentiated. The design detail and the performance of the new BPM as well as preparation of newly installed exciter and power amplifiers will be presented. We will also report beam test results of head-tail mode suppression at 3 GeV with the bunch length of 150-250 ns.
	Slides THOAA03 [1.149 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THOAA03
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THPME130	Development of New Data-taking System for Beam Loss Monitors of J-PARC MR	3547
	K. Satou, N. Kamikubota, T. Toyama J-PARC, KEK & JAEA, Ibaraki-ken, Japan S.Y. Yoshida Kanto Information Service (KIS), Accelerator Group, Ibaraki, Japan
	A new data acquisition system has been developed to improve band-width and dynamic range of the beam loss monitor systems. It consists of isolation current amplifiers with the gain of 1M and the band-width of DC-100kHz, and VME-based 24bit ADCs with the band-width of DC-300kHz and the noise level of 100uV peak to peak. The waveform data of 1MS/s and 1KS/s, and the charge count which is the integrated waveform data are generated and these are compared with alarm levels for the machine protection system. Long-term ground-level stability is essential to monitor residual dose activities. Some beam loss signals include effect of radiations from activated devices, and thus its fractions should be excluded. If the residual dose activities just before the beam injections can be monitored, these fractions would be roughly estimated. Furthermore, on-line monitoring of the residual dose activities after a beam operation will be useful for activation control of the devices at the high level activation area like the collimator and the slow-extraction area. A shot by shot DC offset cancellation is adopted to ensure high ground level stability.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME130
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THPME131	A Multi-conductor Transmission Line Model for the BPMs	3550
	T. Toyama J-PARC, KEK & JAEA, Ibaraki-ken, Japan
	We have developed an accurate and efficient analysis method with a multi-conductor transmission line model for beam position monitors (BPMs). This method combines the two-dimensional electrostatic analysis including beams in the transverse plane and the transmission line analysis in the longitudinal direction. The loads are also included in the boundary condition of the transmission line analysis. Calculation of 2D electrostatic fields can be easily performed with the boundary element method. The BPM response to a beam is compared with that to a stretched wire.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME131
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

THOAA03

Transverse Intra-bunch Feedback in the J-PARC MR

2786

SUSPSNE086

use link to see paper's listing under its alternate paper code

K. Nakamura
Kyoto University, Kyoto, Japan
Y.H. Chin, T. Obina, M. Okada, M. Tobiyama
KEK, Ibaraki, Japan
T. Koseki, T. Toyama
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
Y. Shobuda
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

We will report the development of a new broadband (bandwidth of around 100MHz) feedback system for suppression of intra-bunch oscillations and reduction of particle losses at the J-PARC Main Ring (MR). A new BPM has been designed based on the exponential coupler stripline type (the diameter of 134 mm and the length of 300 mm) and it is now under fabrication. In this BPM system, the frequency characteristics are corrected using the equalizer as bunch signals are differentiated. The design detail and the performance of the new BPM as well as preparation of newly installed exciter and power amplifiers will be presented. We will also report beam test results of head-tail mode suppression at 3 GeV with the bunch length of 150-250 ns.

Slides THOAA03 [1.149 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THOAA03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME130

Development of New Data-taking System for Beam Loss Monitors of J-PARC MR

3547

K. Satou, N. Kamikubota, T. Toyama
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
S.Y. Yoshida
Kanto Information Service (KIS), Accelerator Group, Ibaraki, Japan

A new data acquisition system has been developed to improve band-width and dynamic range of the beam loss monitor systems. It consists of isolation current amplifiers with the gain of 1M and the band-width of DC-100kHz, and VME-based 24bit ADCs with the band-width of DC-300kHz and the noise level of 100uV peak to peak. The waveform data of 1MS/s and 1KS/s, and the charge count which is the integrated waveform data are generated and these are compared with alarm levels for the machine protection system. Long-term ground-level stability is essential to monitor residual dose activities. Some beam loss signals include effect of radiations from activated devices, and thus its fractions should be excluded. If the residual dose activities just before the beam injections can be monitored, these fractions would be roughly estimated. Furthermore, on-line monitoring of the residual dose activities after a beam operation will be useful for activation control of the devices at the high level activation area like the collimator and the slow-extraction area. A shot by shot DC offset cancellation is adopted to ensure high ground level stability.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME130

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME131

A Multi-conductor Transmission Line Model for the BPMs

3550

T. Toyama
J-PARC, KEK & JAEA, Ibaraki-ken, Japan

We have developed an accurate and efficient analysis method with a multi-conductor transmission line model for beam position monitors (BPMs). This method combines the two-dimensional electrostatic analysis including beams in the transverse plane and the transmission line analysis in the longitudinal direction. The loads are also included in the boundary condition of the transmission line analysis. Calculation of 2D electrostatic fields can be easily performed with the boundary element method. The BPM response to a beam is compared with that to a stretched wire.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME131

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)