Analyzing the relationship between the beam lifetime and average gas pressure

For a low-energy third-generation synchrotron storage ring like Taiwan Light Source (TLS), the beam lifetime is a critical issue to determine the future expansion and design criterion of the insertion devices. The beam lifetime also affects the routine operation of the beam energy, from 1.3 GeV to 1.5 GeV has been successfully operated, which could increase the beam lifetime. There were various ways and experiments that have been carried out at TLS to investigate dominating factors of the beam lifetime. The dominating factor of beam life time was intra-beam scattering at 1.3 GeV. From various operation experiences of 1.5 GeV, the dominating factor of overall beam lifetime is changing. A simple algorithm is setup to interpret the relation between residual gas pressure and beam lifetime using archived data during 1.5 GeV normal operation