Residual Gas Analysis on the Daresbury Synchrotron Light Source

Abstract

Residual Gas Analysis (RGA) is a useful diagnostic tool for vacuum systems. One of the original design features of the Daresbury Synchrotron Radiation Source (SRS) vacuum system was a multiplexed, remote operation RGA facility. This has now been operational for more than fifteen years and has been used extensively to monitor vacuum leaks, performance of the vacuum system and contamination levels. By monitoring these parameters routinely, much useful information can be obtained about some of the operational characteristics of the SRS and about warnings of developing leaks or electron beam steering problems. It has not been possible to consistently and reliably monitor the SRS vacuum system in the way intended because of limitations in the multiplexing hardware and control software of the RGA facility. Recently a new multiplexing and data handling system has been developed for us by a commercial company and installed as an upgrade to part of the SRS. In this paper the hardware of the new system is described, a software program to acquire routine RGA data is illustrated and the application of this data to understanding more about the way the SRS “cleans up” after exposure to atmosphere is detailed.