A magnet assembly comprising a superconducting magnet coil system and a magnetic field shaping apparatus for use in a magnetic resonance spectroscopy apparatus and method of manufacturing the assembly.

摘要

A magnet assembly for use in a magnetic resonance spectroscopy apparatus having a superconducting magnet coil system (C) for generating a magnetic field in the direction of a z-axis in a working volume (AV) arranged at z = 0, wherein the field of the magnet coil system has at least one inhomogeneous fraction in the working volume A n0 ⋅zn with n ≥ 2, whose contribution to the total field strength on the z-axis varies by z = 0 with the n-th power of z, and wherein a with respect to the z-axis cylindrically symmetric field shaping device (P1) provided of magnetic material is, which at least partially has a radial distance from the z-axis of less than 80 millimeters and compensates at least one of the inhomogeneous field components A n0 ⋅zn of the magnetic coil system to at least 50%, is characterized in that in the field shaping device one or more non-cylindrically symmetric Recesses are provided which are designed so that at least a coefficient A nm or B nm with m ≠ 0 in the magnetic field development of the magnet arrangement according to spherical functions is reduced in terms of amount by at least 50%. Thus, the field homogeneity in the working volume can be increased substantially simply and without increasing the volume of the magnet arrangement, wherein only a few iterations are required to optimize the magnet arrangement.