Suppression of the Longitudinal Coupled-Bunch Instabilities by the RF Phase Modulation in the Pohang Light Source

Ilmoon Hwang, Moohyun Yoon, Eun-San Kim, Yeung-Jin Han, Jaeseok Yang
Proceedings of the 2005 Particle Accelerator Conference  
In the 2.5 GeV Pohang Light Source, we have investigated the suppression of the longitudinal coupled instabilities (CBI) caused by higher order modes (HOMs) of RF cavities. At higher beam current than 170 mA the 758 MHz or 1300 MHz HOMs occurred and the beam could be unstable. The longitudinal CBI could be suppressed by modulating the phase of an RF accelerating voltage at a frequency of 2 times the synchrotron oscillation frequency and by adjusting the water temperatures of the RF cavities.
more » ... the RF cavities. The longitudinal beam oscillations measured by streak camera in synchro-scan mode were shown. The experiment results were compared with the macro particle tracking simulation.
doi:10.1109/pac.2005.1590976 fatcat:pwvrfr2strfildrpznyaktgyni