Commissioning of RHIC vacuum systems

The Relativistic Heavy Ion Collider (RHIC) has two concentric rings 3.8 km in circumference, There are three vacuum systems in RHIC; the insulating vacuum vessels housing the superconducting magnets, the cold beam tubes surrounded by the superconducting magnets, and the warm beam tube sections at the insertion regions and experimental regions. The vacuum requirements and the design of three vacuum systems are described. The experience gained during the commissioning of these vacuum systems is presented with emphasis on locating helium leaks in the long arc insulating vacuum system.