Vacuum system for the LNLS 500-MeV booster synchrotron

We present a summary of the commissioning and performance of the vacuum system of a 500-MeV booster synchrotron recently built at LNLS as part of a new injector for the LNLS light source. The main vacuum parameters of the synchrotron are pressure below 5 /spl times/ 10/sup -7/ Pa (lifetime of 1-2 hours), no in-situ baking, no cooling system, and a short recovery time after ventilation. All parts of the system are made of 1 mm thick AISI 316L stainless steel. The chambers were pre-baked before installation.