In this paper, we present construction and persistent-mode operation results of a half-scale 1.5-T/54-mm room-temperature bore MgB2 MRI-quality magnet for the development of a tabletop “finger” MRI system. A half-scale magnet, composed of 5 coil sections and a persistent-current switch, was wound with a single ~590-m long unreacted/monofilament MgB2 wire having a superconducting joint, and then heat-treated. We operated the magnet, immersed in liquid nitrogen and cryocooled, successfully, achieving a persistent-mode 1.5-T field at the target operating current of 112 A in the temperature range 10-15 K. We also evaluated a temporal stability and a before-shimmed bare field homogeneity of the magnet by using both a hall probe and an NMR probe. Our discussion includes the spatial field homogeneity difference between as-designed and as-built magnets in consideration of manufacturing tolerance.
Acknowledgement: Research reported in this publication was supported by the National Institute of Biomedical Imaging and Bioengineering of the National Institutes of Health under award number R01EB022062.