Development of a Large-bore Cryocooled Superconducting Magnet for Hybrid Magnets

Abstract

A cryocooled superconducting magnet with a 360-mm room-temperature bore has been developed for hybrid magnets. Magnetic fields of 9.5 T in individual mode operation and 27.5 T in hybrid mode operation were successfully achieved when used in combination with a high-power water-cooled resistive magnet, although quenching occurred at 8.6 T during the first operation due to an unexpected rise in temperature. We discuss the thermal behavior of the innermost coil, where quenching was generated, through the analysis of temperature distribution measurement and two-dimensional thermal conductivity.