Eddy current effects in MRI superconducting magnets

Magnetic resonance imaging (MRI), as well as some volume selected spectroscopy methods, use pulsed magnetic field gradients which induce multi-exponentially decaying eddy currents in all nonlaminated conductive parts of the superconducting magnets. This paper presents the analysis of the z gradient field distorsion due to the induced eddy currents and the corresponding correction in a 4 T/30 cm bore superferric self-shielded magnet.