INVESTIGATION OF BEAM-ORBIT FLUCTUATION OBSERVED IN DAILYOPERATION OF THE KEKB INJECTOR LINAC
T.Suwada1,Accelerator Laboratory, High Energy Accelerator Research Organization,
1-1 Oho, Tsukuba, Ibaraki, 305-0801
Abstract
The KEKB injector linac steadily injects electron and positron beams to perform the KEK B-factory experimentdirectly to the KEKB storage rings. We observe sudden transverse position displacement just after the pre-injector
section for a primary high current electron beam for positron production once (or twice) in average in daily operation
since the KEKB operation started in 1997. A lot of hardware devices have been developed in order to stabilize eachcomponent, and however, it has not been clear yet what kind of origin causes such strange phenomena. In this report theauthor will describe a hypothetical mechanism to induce the beam instability, which is caused by electrification andelectric discharge of a ceramic insulator used for a wall-current monitor.

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E-mail: tsuyoshi.suwada@kek.jp

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