Design and Test of a Curved Canted–Cosine–Theta Superconducting Dipole Magnet for Next Generation Ion Therapy

The curved superconducting dipole magnet is the core component of the next generation ion therapy device. The superconducting dipole magnet prototype with a physical bend angle of 90°, a magnetic bend angle of 45°, a bend radius of 800 mm, and a bore of 98 mm diameter is developed in China based on a novel type of canted–cosine–theta (CCT) coil structure. The magnet design and manufacturing, and the quench protection system are reported first, and then the testing process of this curved CCT superconducting magnet, which reached the nominal current of 610 A and generated the magnetic field of 2.018 T, after five quench trainings in liquid helium test is reported, meeting the design indicators. A set of technical routes is explored through the development of the curved CCT magnet, providing support for the future ion therapy.