| 摘要 |
PROBLEM TO BE SOLVED: To provide a persistent current superconducting magnet suitable for a high magnetic field NMR apparatus whose magnetic field has an decay rate of not lager than 0.01 pm/hr and is made very stable spatiotemporally in magnetization. SOLUTION: A persistent current superconducting magnet having a persistent current superconducting magnet comprising superconducting coils 3, 13 for generating a main magnetic field and a persistent current switch 4, and a persistent current superconducting magnet comprising a superconducting coil 5 for compensating the decay of the main magnetic field and a persistent current switch 6, wherein the superconducting coil 5 for compensating the decay of the main magnetic field has no magnetizing power supply and is coupled magnetically to the superconducting coils 3, 13 so that currents are mutually induced in the coils 3, 13 by the coil 5 corresponding to the decay of the main magnetic field caused by the decay of the currents in the coils 3, 13. |
