The Culham superconducting levitron

The evolution of high energy plasma confinement systems culminating in a system, the levitron, which utilises a superconducting levitated ring to trap the plasma, is traced. The stability, handling and the specifications of the Culham ring is described and the design details of the cryogenic support structure, the refrigerator system and the liquid nitrogen circulating system of the system, are given. Operational experience already obtained on the machine is discussed. (U.K.)