Design and Electromagnetic Analysis of a CAR-HTS Dipole Magnet for Heavy-Ion Therapy Gantry

High-temperature superconducting (HTS) magnets have high current density and operate at elevated temperatures, making them suitable for medical imaging, particle accelerators, power transmission, and scientific research. To address the requirements for compact size and improved energy efficiency in heavy-ion therapy gantry systems, this paper proposes a combined arc-shaped racetrack HTS dipole magnet (CAR-HTS dipole magnet) for fast time-varying operation. The magnet is designed to generate a 4 T central field with a bending radius of 1650 mm and an integrated field uniformity better than 0.1% within a ±10 mm good-field region. The magnetic field distribution is optimized using coupled MATLAB–COMSOL simulations, followed by prototype fabrication and cryogenic excitation tests. The experimental results demonstrate the feasibility of the proposed magnet structure and field performance, supporting the design and application of HTS dipole magnets.