Design of Prototype Magnets for HUST Proton Therapy Beamline

A proton therapy facility with two 360° gantry treatment rooms and one fixed beamline is under development at the Huazhong University of Science and Technology (HUST), which is based on an isochronous superconducting cyclotron. The energy is modulated in the range of 70-240 MeV with an energy selection system. In this paper, we report the main design specifications of the beamline in the HUST-PTF project, in which the main features are the intensity suppression scheme beamline. Two prototype magnets (one quadrupole and one dipole) used in the beamline are also studied and presented. Two-dimensional contour optimization and pole-end chamfer iteration are used to minimize the harmonic errors of the integral field. Finally, both the field homogeneity and multipole errors achieve the precision requirement over the operating field range.