Magnet system

A magnet system for generating a uniform magnetic field in a target region is provided. The magnet system comprises: a first magnet formed by winding a low temperature superconductor (LTS) material to define a central axis, the first magnet being arranged, in use, to generate a first magnetic field in a target region located on the central axis, the first magnetic field having a first level of uniformity; a second magnet formed of a high temperature superconductor HTS material and arranged to, in use, generate a second magnetic field in the target region, the second magnetic field having a second level of uniformity. The uniformity of the first level of the first magnetic field is up to 10 ppm, and the uniformity of the second level of the second magnetic field is up to 10 ppm, the combination of the first magnetic field and the second magnetic field in the target region in use generates a resulting magnetic field having a resulting uniformity up to 10 ppm, and wherein the first magnet and the second magnet a