Prototype bunch killer system at SRRC

Abstract

The prototype bunch killer has been set up at SRRC recently. The system includes two subsystems, the multibunch filling pattern shaping system and single bunch killer system. Gate RF knockout approach is used to shape the filling pattern of multibunch and to obtain a well-defined gap for machine study. The gate processes synchronize with revolution frequency. Widths of the gate signal determine the empty gap of the filling pattern. Beam knockout systems with nanosecond impulse current are also implemented which used to kill the individual electron bunch with bucket addressing capability. The purity of the single bunch is improve by the nanosecond knockout system, despite the difference of the tune and tune spread of the main and parasitic bunches, that lifts the requirement of the narrow tune spread for standard single bunch purification process. The nanosecond knockout technique also applied to kill undesired bunches in the multibunch operation mode. The preliminary results are present.

Performance of the SRRC storage ring and wiggler commissioning

“…A bunch current up to 30 mA could be accumulated in a few minutes and bunch purity could be better than loq3 with bunch purification process. [4] We observed severe transverse beam instability' in particular in the vertical plane. At least up to present, this instability was attributed to the beam-ion interaction.…”