PERFORMANCE OF THE TRANSVERSE COUPLED-BUNCH FEEDBACK SYSTEM IN THE SRRC

A transverse feedback system has been implemented and commissioned in the SRRC storage ring to suppress transverse coupled-bunch oscillations of the electron beam. The system includes transverse oscillation detectors, notch filter, baseband quadrature processing circuitry, power amplifiers and kickers. To control a large number of transverse coupled-bunch modes, the system is broad-band, bunch-by-bunch in nature. Because the system is capable of bunch-by-bunch correction, it can also be useful for suppressing instabilities introduced by ions. The sextupole strength was then reduced to improve dynamic aperture and hence the lifetime of the storage ring. 1