Helium Infrastructure of the Cryogenic Complex for the Collider: Results of Preparation for the Technological Session

The technological session of the Collider ring is scheduled for early 2025. The session program includes cooling magnets to operating temperature of 4.5 K, testing the magnetic-cryostat system for leaks, testing with the operating current into the magnets, and checking the operability of the correctors. New equipment of the cryogenic complex will be used to cool the magnets: refrigerators RSG Nos. 2 and 3, helium liquefier OG-1000, cold helium storage KTsG-40/0.5 and an extensive manifold of cryogenic pipelines. Results of testing new cryogenic complex facilities are presented and technological solutions that will provide the optimal operating mode of the accelerator equipment at helium temperatures are described.