WEPS118

Proceedings of the 7th Annual Meeting of Particle Accelerator Society of Japan (August 4-6, 2010, Himeji, Japan)
BEAM TEST OF CHOPPED BEAM LOADING COMPENSATION
FOR THE J-PARC LINAC 400-MeV UPGRADE
Tetsuya Kobayashi1,A), Masanori IkegamiB)
A)
Japan Atomic Energy Agency (JAEA)
2-4 Shirakata-Shirane, Tokai, Naka, Ibaraki, 319-1195
B)
High Energy Acceleration Research Organization (KEK)
1-1, Oho, Tsukuba, Ibaraki, 305-0801
Abstract
The function of the chopped beam loading compensation was implemented into the digital feedback/feed-forward
control system of the J-PARC Linac LLRF system to stabilize the ACS cavity fields for the 400-MeV upgrade.
The beam test of the chopped beam loading compensation was performed with the present 324-MHz cavity sysmte.
As the result, the chopped beam loading was successfully compensated and that this system is valid.
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Proceedings of the 7th Annual Meeting of Particle Accelerator Society of Japan (August 4-6, 2010, Himeji, Japan)
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Proceedings of the 7th Annual Meeting of Particle Accelerator Society of Japan (August 4-6, 2010, Himeji, Japan)
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[1] URL: http://www.j-parc.jp/
[2] S. Michizono, et al., “Digital Feedbac Control for 972-MHz
RF System of J-PARC Linac”, Proc of PAC09,
WE5PFP082, 2009
[3] S. Wang, S. Fu and T. Kato, "The development and beam
test of an RF chopper system for J-PARC", Nuclear
Instruments and Methods in Physics Research A 547, pp.
302–312, 2005.
[4] S. Michizono, et al., “Performance of a Digital LLRF Field
Control system for the J-PARC Linac", Proc. of
LINAC2006, pp. 574-576, 2006
[5] T. Kobayashi, et al., "Performance of J-PARC Linac RF
System", Proc of PAC07, pp. 2128-2130, 2007
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