Proposed High Performance Refrigeration Cycles to Obtain Superconducting Operation of a Two-Mile Linear Accelerator at 1.85K, 1.425K, or 1.0K

The existing two-mile linear electron accelerator at SLAC has a duty cycle of less than 0.1% and is limited to 20 GeV. If it were converted to superconducting operation, the duty cycles might be 100% at 20 GeV and 6% at 100 GeV. This paper discusses high performance refrigeration cycles as necessary to make superconducting operation of a two-mile linear accelerator most reliable and least costly.