Monte Carlo simulation of NaI(Tl) detector and GRAVEL deconvolution for biological, geological samples and their dosimetry evaluation

Abstract

A new approach for natural radioactivity evaluation in environmental samples was presented. The method was based on the combination of GRAVEL unfolding code and Monte Carlo simulation. The NaI(Tl) detector model was validated by comparing the simulated data with the experiment using a calibration point source. Then, the response matrixes at 1.46 and 1.76 MeV corresponding to 40K and 238U respectively, was used to restore the incident γ spectra. The measured activities were used to estimate the biological activities and the annual absorbed doses. The annual absorbed doses are lower than the worldwide reference value of 1 mSv·y-1.