Recent experiments on the fast beam-ion instability and a study of potential cures at the ALS and PEP-II

摘要

The authors report their latest experiments on the fast beam-ion instability (FBII) at the Advanced Light Source (ALS). In October 1997, they studied the pressure dependence of the instability, and tested the effectiveness of two proposed cures: a large chromaticity and additional gaps in the bunch train. They also describe a very preliminary observation of increased rms motion along the PEP-II electron bunch train, which is tentatively attributed to the FBII.