Study of dose rate in the brain model based on the neutron beam of SUT-MNSR

Boron neutron capture therapy (BNCT) is tumor-cell targeted radiotherapy that has significant superiority over conventional radiotherapies. The most neutron beams used for BNCT are from the reactors with high power, new design Miniature Neutron Source Reactor(MNSR) with 45kW with BNCT beam for Suranaree University of Technology(SUT) is being designed and built. According to SUT-MNSR physics design, SUT-MNSR will have the epithermal neutron beam for BNCT treatment. The dose rate distribution in the body should be estimated before SUT-MNSR is used for BNCT clinical trials (Brain tumor). This paper introduces the simulation for SUT-MNSR neutron beam by Monte Carlo N-Particle Transport Code (MCNP), and the establishment of human brain model and physics dose rate distribution in brain tumor by MCNP program.The brain model is established according to the different element in the skin, skull and tissue, the distribution of neutron dose and Gamma dose in the brain model were calculated.