Development of a superconducting magnet plasma research facility

To conduct plasma research with a steady-state high magnetic field, a magne tic mirror system with a pair of superconducting magnets (SCMs), named Supe rconducting Magnet Plasma Research Facility (SPRF), is under development. M ajor components of the system are a pair of NbTi solenoid SCMs, two cryosta ts, a plasma chamber, and a de power supply. Each SCMs is separated by l-m distance and operated at 800 A. The magnetic flux density on the axis of th e SPRF is 0.23 T at the mid point and 3.1 T at the magnet center, which giv es the mirror ratio of 13.4. In this paper, we describe the design consideration of SPRF, including the development activities of the magnets and the cryostats. Also, the test res ults of the magnets and the cryostats are described.