The BaBar superconducting coil: design, construction and test

The BABAR Detector, located in the PEP-II B-Factory at the Stanford Linear Accelerator Center, includes a large 1.5 Tesla superconducting solenoid, 2. 8 m bore and length 3.7 m. The two layer solenoid is wound with an aluminum stabilized conductor which is graded axially to produce a +/- 3% field uni formity in the tracking region. This paper summarizes the 3 year design, fa brication and testing program of the superconducting solenoid. The work was carried out by an international collaboration between INFN, LLNL and SLAC. The coil was constructed by Ansaldo Energia. Critical current measurements of the superconducting strand, cable and conductor, cool-down, operation w ith the thermo-siphon cooling, fast and slow discharges, and magnetic force s are discussed in detail.