NEW BEAM DIAGNOSTICS AND RELATED STUDY ON HLS PHOTO- INJECTOR AND HLS II*

A team in NSRL is now doing research about small model accelerators and carrying out series of related experiments on HLS photo-injector and HLS II storage ring. Cavity beam multi-parameter monitor system designed for the HLS photocathode RF electron gun consists of a beam position monitor, a beam quadrupole moment monitor and a beam density and bunch length monitor. TM0n0 modes of cavity can be used to work out beam density and bunch length simultaneously. Miniaturization of FEL facilities is now being studied based on results of experiments and theoretical work before. The team also participate in commissioning of HLS II, i.e. measured the tune of the new storage ring and did some research on longitudinal bunch-by-bunch feedback system.