ABSTRACT
In this work TLD-200 (CaF2:Dy) chips were used to measure the gamma-ray doses in a PMMA phantom exposed to the BNCT beam at Tsing Hua Open-pool Reactor (THOR). The self-irradiation component induced by the decay of Dy-165 was corrected. The neutron dose contamination was less than 0.3%. The Dy content in the TLD-200 chip was determined by using the modified absolute calibration method of NAA. The self-irradiation TL signal was also applied for the in situ calibration.
Subject(s)
Boron Neutron Capture Therapy , Gamma Rays , Neutrons , Calibration , Dose-Response Relationship, Radiation , Monte Carlo Method , Phantoms, Imaging , Quality ControlABSTRACT
TLD-400 (CaF2:Mn) chips were applied for the gamma-ray dose measurement in a PMMA phantom exposed to a BNCT beam because of their very low neutron sensitivity. Since TLD-400 chips possess an adequate amount of Mn activator they have been employed in this work simultaneously for neuron activation measurement. The self-irradiation TL signals owing to the decay of the neutron induced 56Mn activity have been applied for a calibration of the TLD-400 chip in situ, where the activities were measured by an HPGe detector system and the energy deposition per disintegration of 56Mn was calculated by applying a Monte Carlo code. It was accidentally found that the irradiated TLD-400 chips were capable of emitting prominent scintillation lights owing to the induced 56Mn activity, which can easily be recorded by the TLD reader without heating and after a calibration can be used to determine the 56Mn activity.