Design and testing of the 1.5 T superconducting solenoid for the BaBar detector at PEP-II in SLAC

The 1.5 T superconducting solenoid is part of the BaBar detector located in the PEP-II B-Factory machine at the Stanford Linear Accelerator Center. The solenoid has a 2.8 m bore and is 3.7 m long. The two layer solenoid is wound with an aluminum stabilized conductor which is graded axially to produce a +/3% field uniformity in the tracking region. The 24 month fabrication, 3 month installation and 1 month commissioning of the solenoid were completed on time and budget. This paper summarizes the culmination of a 3 year design, fabrication and testing program of the BaBar superconducting solenoid. Critical current measurements of the superconducting strand, cable and conductor, cool-down, operation with the thermosyphon cooling, fast and slow discharges, and magnetic forces are discussed in detail.