Concept Design of a Superconducting Magnet for a Compact Heavy-Ion Synchrotron
Kota Mizushima, Ye Yang, T. Fujimoto, Y. Iwata, Shunya Matsuba, Yasushi Abe, Etsuo Noda, Masami Urata, Toshiyuki Shirai, Tomofumi Orikasa, Shigeki Takayama, Saki Amano, K. Nakanishi, Yutaka Hirata
Abstract
A compact synchrotron is now under development at the National Institutes for Quantum Science and Technology (QST), with the goal of downsizing the heavy-ion therapy system with superconducting magnets conduction-cooled by GM cryocoolers. The synchrotron is required to accelerate several kinds of heavy-ion beams from 4 MeV/u to 430 MeV/u. A superconducting magnet with both dipole and quadrupole coils is adopted to generate a dipole field from 0.3 to 3.5 T and a quadrupole field from 0.1 to 1.5 T/m with a ramp rate of 0.6 T/s. A coil winding pattern and iron yoke are optimized to achieve field homogeneity in the required area. For the small-scale synchrotron, the coil ends are optimized with a novel parameter combining the beta function and multipole errors considering the beam dynamics.