[2L09-12] Medical RI and Accelerator

[2L12] Comparison of components and radiation characteristics for an electron accelerator-based neutron source with those of proton accelerator-based neutron source for boron neutron capture therapy

*Tomohiko Sejima¹, Fujio Hiraga² (1. Hokkaido University Graduate School of Engineering, 2. Hokkaido University School of Engineering)

Keywords:Boron Neutron Capture Therapy (BNCT), accelerator-based Neutron Source, photoneutron, neutrons from irradiation of a beryllium target by 30-MeV-protons

Accelerator-based BNCT neutron sources that use neutrons from irradiation of a beryllium target by 30-MeV-protons or a tungsten target by 42.5-MeV-electrons were designed by Monte Carlo simulations. The thicknesses of filters and a moderator for the neutron sources were examined so that the neutron sources produced neutron beams with a fast-neutron dose per epithermal neutron of about 6×10^-13 Gy cm². Both the neutron sources driven by a proton beam of 22.1 kW or an electron beam of 27.0 kW created the epithermal neutron flux at a treatment position of 2×10⁹ cm^-2 s^-1 adequate for BNCT. Further, the filters and a moderator for the proton-accelerator-based neutron source became 25 cm thicker than the electron-accelerator-based neutron source.