The NHMFL 45-T hybrid magnet system: past, present, and future

A hybrid magnet system, combining superconducting and resistive magnet technologies for the production of 45-T steady field in a 32-mm room-temperature bore, has been operated successfully as a user facility for the past two years at the National High Magnetic Field Laboratory in Tallahassee, Florida. The superconducting outsert is a 710-mm bore magnet with demonstrated capability for 100-MJ stored energy, over 14-T field on axis, and nearly 16-T maximum field at the windings. This system continues to provide to researchers the highest steady field available anywhere in the world, even after degradation of the superconducting outsert, which resulted from an "unprotected" quench in July 2000. This paper reviews the important specifications and design features for the superconducting outsert, its nearly 3-year history of operation, as well as plans for its repair and future upgrades.