Modeling the thermoluminescent response of CaSO4:Dy by the MCNPX method

This work describes an algorithm for absorbed dose evaluation in the region of X-ray diagnostic energy based on the response of CaSO4:Dy thermoluminescence powder detectors. The absorbed dose was calculated using Monte Carlo simulation code (MCSC) and then compared to the experimental TLD results for X-rays effective energies 60Co gamma radiation. In order to study the photon interaction in the matter, a cylindrical model of 1 cm3 was used. The gamma radiation source was placed at 100 cm to the object; the source is considered as an isotropic source of 60Co. The energy deposited into the cylindrical model was determined by the Monte Carlo N-particle (MCNPX) method. Measurements of the TL phosphors were obtained by irradiating the powder by gamma radiation. TL glow curve of CaSO4:Dy after gamma irradiated at a 1 Gy of absorbed dose was then obtained.