Beam Diagnostics by Gating a Single Bunch at Kekb
نویسندگان
چکیده
A fast gate module has been developed at KEKB, which can pick up a signal of one bunch along a bunch train. The gate module was attached to a tune measurement system and to a turn-by-turn beam-position monitor system. Continuous monitoring of the betatron tune is an indispensable tool to keep the machine in a stable condition. A measurement of the tune along a bunch train is helpful to estimate the photoelectron cloud density in the Low-Energy Ring (LER). A large tune shift was observed in the High-Energy Ring (HER). The bunch phase is shifted along a train, which can be explained using a periodic transient beam-loading effect.
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