A new tool for beam-life research at HLS storage ring

A beam loss monitoring system was set up for HLS (Hefei Light Source) last year. The beam loss message includes some beam life related factors. So, besides detecting vacuum failures in the storage ring, this system may serve as a useful tool in beam life research. The beam life is composed of three parts: Touschek life, quantum life and vacuum life. The exact loss position of the corresponding stored electrons can be concluded if we detect shower electrons, which give a distinct clue of loss location, but not to detect bremsstrahlung photos or neutrons. So it is important to analyze the positions where beam losses take place and qualitatively distinguish them. With the help of this system, the researchers have found and resolved following problems: A 20-40 mA beam loss frequently observed during ramping process; vacuum dead area near the front ends of beam lines; a beam life decline when a 6-Tesla superconducting wiggler was powered; etc.