Commissioning and Testing the 1970's Era LASS Solenoid Magnet in JLab's Hall D

JLab refurbished and reconfigured the LASS 1.85-m bore Solenoid and installed it as the principal analysis magnet for nuclear physics in the newly constructed Hall D at Jefferson Laboratory. The magnet contains four superconducting coils within an iron yoke. The magnet was built in the early 1970s at Stanford Linear Accelerator Center and used a second time at Los Alamos National Laboratory. The coils were extensively refurbished and individually tested by JLab. A new Cryogenic Distribution Box provides cryogens and their control valving, current distribution bus, and instrumentation pass-through. A repurposed CTI 2800 refrigerator system and new transfer line complete the system. We describe the reconfiguration, the process and problems of recommissioning the magnet, and the results of testing the completed magnet.