Proceedings of the 2nd Annual Meeting of Particle Accelerator Society of Japanand the 30th Linear Accelerator Meeting in Japan (July 20 - 22, 2005, Tosu Japan)

INVESTIGATION OF BEAM-ORBIT FLUCTUATION OBSERVED IN
DAILY OPERATION OF THE KEKB INJECTOR LINAC (II)Tsuyoshi Suwada1,Accelerator Laboratory, High Energy Accelerator Research Organization,
1-1 Oho, Tsukuba, Ibaraki, 305-0801
Abstract
We have observed sudden transverse beam position displacement just after the pre-injector section for a primary highcurrent electron beam for positron production once (or twice) in average in daily operation since the KEKB operation
started in 1997. Such strange phenomena and the investigated results were reported at the previous LINAC meeting.
Since then, a test with the beam and a bench test were performed to further investigate and to understand thephenomena. These test results show that a sudden electric discharge after the electrification of a ceramic insulator used
for a wall-current monitor were a main origin causing the beam-orbit fluctuation.

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1E-mail: tsuyoshi.suwada@kek.jp-415-

Proceedings of the 2nd Annual Meeting of Particle Accelerator Society of Japanand the 30th Linear Accelerator Meeting in Japan (July 20 - 22, 2005, Tosu Japan)

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Proceedings of the 2nd Annual Meeting of Particle Accelerator Society of Japanand the 30th Linear Accelerator Meeting in Japan (July 20 - 22, 2005, Tosu Japan)

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