Mechanical and Thermal Considerations for the Superconducting Magnet to Normal Conductor Magnet “Warm-to-Cold Transitions” of the RHIC Accelerator

Abstract

The RHIC accelerator, designed for maximum flexibility, allows for the insertion within the superconducting magnet lattice of specialty magnets of the normal conductor type. The beam character may then be customized at each of the experimental crossing points. This facility requires a beam tube transition from a cryogenic environment to ambient and back again. The “Warm-to-Cold Transition” is the system of mechanical and electrical components which permit this to occur. Discussed herein are: the systems mechanical degrees of freedom, shrinkage allowances, thermal and pressure induced stresses, cryogenic heat load, superconducting bus splices, and design considerations for each of the eight major assemblies.