Tests with RF feedback and Landau damping
نویسندگان
چکیده
Tests were made with an RF feedback system with increased bandwidth around the 200 MHz Travelling Wave Cavities. The high intensity beam was stabilised just after injection but became again unstable at higher energies. Addition of the 800 MHz RF system in bunch shortening mode stopped instabilities at energies up to 450 GeV but could not control them on the flat top at maximum 200 MHz RF voltage. A new technique to calibrate the absolute phase and amplitude of the 800 MHz voltage was tested.
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