Electron Cloud Effects in Kekb
نویسنده
چکیده
Measurements of the electron cloud effects in KEKB have been done since ECLOUD02 workshop. The results are summarized as 1) strength of the solenoid field in the present solenoid system is not enough to suppress the blow-up of the vertical beam size at high bunch currents and/or narrow bunch spacing, 2) solenoids in straight sections as well as arc sections contribute to suppress the electron cloud, 3) wiggler magnets have an effect on the blow-up of the vertical beam size but not on the tune shift and 4) regions where field orientation of adjacent solenoids changes have almost no effect on the blow-up and the tune shift and 5) a vertical tilt along a bunch, which might be an indication of the head-tail instability due to the electron cloud, is not clearly observed by the measurement by a streak camera.
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