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http://dx.doi.org/10.9714/psac.2018.20.2.029

Passive shimming design with commercially available rectangular shim sheets on a cylinder for HTS NMR magnets

Ahn, Min Cheol (Kunsan National University)

Publication Information

Progress in Superconductivity and Cryogenics / v.20, no.2, 2018 , pp. 29-33 More about this Journal

Abstract

Although high-temperature superconducting (HTS) magnets have the potential merit of producing ultra-high field (>25 T), they have been not easy to apply to Nuclear Magnetic Resonance (NMR) because of the difficulty of field homogeneity improvement. This paper presents a design technique of passive shimming for HTS magnets. Ferromagnetic shimming design code was developed though MALAB, which includes the optimization algorithm. The proper shim element size was determined by a simulation. This design technique was verified by a case study design of a 3-T HTS magnet. We succeed to improve field homogeneity of the magnet from 634 ppm to 6.39 ppm at 10-mm diameter sphere volume. Feasibility of passive shimming for all-HTS NMR magnet was confirmed by this result.

Keywords

HTS magnet; ferromagnetic shimming; passive shimming;

Citations & Related Records

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