Field uniformity enhancement in a prototype high-temperature superconducting dipole magnet

High-temperature superconducting (HTS) magnets are applied across MRI, NMR, and fusion, and particle accelerators are likewise advancing toward higher magnetic fields, creating a need for high-field magnets. In synchrotrons, high-field dipole magnets of saddle geometry are required, and REBCO has drawn attention as a promising material to realize them. For these applications, the magnetic field must be spatially homogeneous along the beam line and temporally stable. However, for REBCO dipole magnets, there are few studies that rigorously report field uniformity and temporal stability on the beam line, and efforts to improve the uniformity itself remain scarce. Here we demonstrate improved field uniformity in a conduction-cooled, no-insulation (NI) REBCO saddle dipole magnet engineered to produce a 0.5 T central field. Two strategies to mitigate magnetic field uniformity due to screening-…