Vacuum chamber and crotch absorber for the SPring-8 storage ring vacuum system

The whole vacuum system for the SPring-8 storage ring is planning to be completely installed in the ring by October 1996. The vacuum chamber for the straight sections consists of a beam chamber and a slot-isolated antechamber in which NEG strips are installed To suppress the chamber deformation at the BPM station due to the pressure difference between the atmospheric pressure and the vacuum, ribs are mounted on the chamber In the bending magnet chamber, a distributed ion pump is also installed. The crotch and absorber have been designed to reduce their RF impedances and the radiation level outside the vacuum chamber. In this paper we present details of the final design for the vacuum chamber, crotch and absorber. The chamber supporting system and the structure of ribs are also described.< >