Cooling the Argonne National Laboratory superconducting heavy-ion linac with two refrigerators in parallel

The Argonne Superconducting Heavy Ion Linac is described with appropriate history and illustration, including a side view of a cryostat. Linac components are given with totals and approximate heat loads. The helium flow system is described with a plan view of superconducting linac cryostates and helium distribution system diagrammed. Additions to the cryogenic system are outlined, including the extension of the main helium distribution line, phase separator and transfer lines, and model 2800 refrigerator and compressors. The operating experience is reported with apposite examples