Estimation of photon and neutron dose distributions in the THOR BNCT treatment room using dual TLD method

Dual detector dosimetry using the paired detectors, TLD-600 and TLD-700 chips, were selected in this study to distinguish the doses of neutrons and photons in Tsing Hua Open-pool Reactor (THOR) boron neutron capture therapy (BNCT) preclinical test. Since the neutron response of TLD is dependent on the neutron spectrum, responses of TLD-600 and TLD-700 for neutrons and photons were estimated by irradiation methods and in addition the effect of the neutron spectrum on the TLD response was studied by Monte Carlo simulations in present work. A sectional ART head phantom was used to be irradiated with the THOR BNCT beam. TLD-600 and TLD-700 chips were placed inside the phantom to measure and distinct the doses of neutrons from photons. Besides, dual TLD chips were placed in plane of the room space area to estimate the spatial dose distributions in the THOR BNCT treatment room. A cube water phantom was used to consider the deviation between the two algorithms used in this work. In the results, neutron and photon dose distributions in phantom and the spatial dose distributions in THOR BNCT treatment room were estimated; characteristics and the treatment indexes for BNCT were also assessed.