Superconducting compensator magnets to be used with the HRS spectrometer at the SLAC PEP facility

The first of a pair of identical superconducting compensator solenoids required for the High Resolution Spectrometer Facility (HRS) at the Stanford e+ e- Colliding Beam Storage Ring Accelerator (PEP) has been tested. The magnet provides a 2.0 T field in a room temperature bore 19.0 cm in diameter. The magnet winding length is 1.65 m and a cold iron yoke reduces the fringe fields 30 cm outside the cryostat to less than 10 gauss. The pool-boiling helium cryostat with liquid nitrogen cooled thermal radiation shield will be supplied with cryogens from the Spectrometer Facility refrigeration system.