The 45T hybrid insert: recent achievements

The NHMFL hybrid magnet was successfully tested to 45.1 T in an air bore as designed on June 26, 2000. The magnet consists of a cable-in-conduit superconducting outsert producing 14.3 T in a 616 mm bore and a Florida-Bitter resistive insert providing 30.8 T in a 32 mm bore. The insert was tested without the outsert in May 1999. The combined system was tested in December 1999 reaching a peak field of 44 T in an air bore. Physics experiments were run in December 1999 at 45 T using dysprosium pole piece flux concentrators. During the first and second quarters of 2000 modifications were made to the cryogenic system and the resistive insert. Test results of the resistive insert from December 1999 to June 2000 are presented along with a discussion of the possibilities of upgrading the insert to reach a total held of 50 T. Scientific experiments are scheduled up to 45 T in a clear bore starting July 3, 2000. A spare set of resistive coils is under construction. (C) 2001 Elsevier Science B.V. All rights reserved.