RF electromagnetic design and multi-physics analysis of CW CH-DTL for AB-BNCT

Abstract The accelerator-based boron neutron capture therapy (AB-BNCT) facility is being developed worldwide due to its advantages, including easy maintenance, low construction costs, and high safety. To minimize both the length and cost of the accelerator, we propose a combined acceleration structure that utilizes a radiofrequency quadrupole linac (RFQ) in conjunction with a crossbar H-mode drift tube linac (CH-DTL). The CH-DTL rapidly accelerates the beam to the required energy after the RFQ, with output energy adjustable from 2.2 MeV to 3.2 MeV. We have completed the RF electromagnetic design and optimization of the CH-DTL cavity to fulfill beam dynamics requirements while achieving high effective shunt impedance. Additionally, we designed the cooling channels and conducted multi-physics analyses to evaluate the cavity's performance during continuous wave operation.