IPAC2014 - List of Authors (Hayashi, N.)

Paper	Title	Page
TUPRI051	Comparison between Measurements and Orbit Code Simulations for Beam Instabilities due to Kicker Impedance in the 3-GeV RCS of J-PARC	1683
	P.K. Saha, H. Harada, N. Hayashi, H. Hotchi, Y. Shobuda, F. Tamura, M. Yamamoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	The transverse impedance of the extraction kicker magnets is the most dominant beam instability source in the 3-GeV Rapid Cycling Synchrotron of J-PARC. The instability occurs when chromaticity is fully corrected during acceleration but on the other hand no instabilities are observed for a full chromatic correction only at the injection energy even for a beam power up to 500 kW. However, the situation may change for a beam power of 1 MW and also for the upgraded injection beam energy from the present 181 MeV to the 400 MeV, as space charge effect in the non-relativistic region is believed to suppress the growth rate of beam instability. In order to study the kicker impedance in detail, recently we have introduced measured time dependent impedance source in the ORBIT simulation code in a realistic manner. The ORBIT code itself has also been well upgraded and given realistic features for application to synchrotrons. We have also carried out a systematic experimental study for a maximum beam power of 500 kW. In this paper, a detail comparison between measurements and corresponding simulations including 1 MW simulation results are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI051
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THPME063	Residual Dose with 400 MeV Injection Energy at J-PARC Rapid Cycling Synchrotron	3379
	K. Yamamoto, N. Hayashi, M. Kinsho JAEA/J-PARC, Tokai-mura, Japan
	Last summer shutdown J-PARC RCS injection energy was upgraded from 181 MeV to 400 MeV. We report the effect of the injection energy upgrade on the residual dose in the RCS.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME063
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THPRI016	Pulse Based Data Archive System and Analysis for Current and Beam Loss Monitors in the J-PARC RCS	3800
	N. Hayashi, S. Hatakeyama, K. Yamamoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	The data archive system in the J-PARC 25-Hz Rapid-Cycling Synchrotron (RCS) records the beam intensity and the beam loss monitor (BLM) pattern for all pulses. The system is based on the common memory and utilizes the timing system of the J-PARC. Although its time resolution is limited, it is useful to detect rare events or phenomena appearing with only higher accelerator repetition. Using these data, the stability of the beam intensity, particularly ion source can be examined. The relation between BLM patterns and its causes can be studied pulse-by-pulse basis and it would make use of future improvements.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI016
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Paper

Title

Page

Comparison between Measurements and Orbit Code Simulations for Beam Instabilities due to Kicker Impedance in the 3-GeV RCS of J-PARC

1683

P.K. Saha, H. Harada, N. Hayashi, H. Hotchi, Y. Shobuda, F. Tamura, M. Yamamoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

The transverse impedance of the extraction kicker magnets is the most dominant beam instability source in the 3-GeV Rapid Cycling Synchrotron of J-PARC. The instability occurs when chromaticity is fully corrected during acceleration but on the other hand no instabilities are observed for a full chromatic correction only at the injection energy even for a beam power up to 500 kW. However, the situation may change for a beam power of 1 MW and also for the upgraded injection beam energy from the present 181 MeV to the 400 MeV, as space charge effect in the non-relativistic region is believed to suppress the growth rate of beam instability. In order to study the kicker impedance in detail, recently we have introduced measured time dependent impedance source in the ORBIT simulation code in a realistic manner. The ORBIT code itself has also been well upgraded and given realistic features for application to synchrotrons. We have also carried out a systematic experimental study for a maximum beam power of 500 kW. In this paper, a detail comparison between measurements and corresponding simulations including 1 MW simulation results are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI051

Export •

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

THPME063

Residual Dose with 400 MeV Injection Energy at J-PARC Rapid Cycling Synchrotron

3379

K. Yamamoto, N. Hayashi, M. Kinsho
JAEA/J-PARC, Tokai-mura, Japan

Last summer shutdown J-PARC RCS injection energy was upgraded from 181 MeV to 400 MeV. We report the effect of the injection energy upgrade on the residual dose in the RCS.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME063

Export •

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

THPRI016

Pulse Based Data Archive System and Analysis for Current and Beam Loss Monitors in the J-PARC RCS

3800

N. Hayashi, S. Hatakeyama, K. Yamamoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

The data archive system in the J-PARC 25-Hz Rapid-Cycling Synchrotron (RCS) records the beam intensity and the beam loss monitor (BLM) pattern for all pulses. The system is based on the common memory and utilizes the timing system of the J-PARC. Although its time resolution is limited, it is useful to detect rare events or phenomena appearing with only higher accelerator repetition. Using these data, the stability of the beam intensity, particularly ion source can be examined. The relation between BLM patterns and its causes can be studied pulse-by-pulse basis and it would make use of future improvements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI016

Export •

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