Photon dosimetry based on selective data sampling for the NaI(TL) detector

Authors

Abstract

Radiation detection is essential for determining of radiation dose. Depend on the detector and dosimetry method, detection process is performed in different levels. Pulse counting is the first level of detection. Typically, the output of a radiation detector for determining value of the radiation dose cannot be used directly. Through changing the response function or the readout detector, is trying to create relevance and proportionality between detector readout and value of the dose equivalent. For this purpose, there are various software methods and hardware methods are obtained dose equivalent values. Software methods such as convolution, Deconvolution, etc. and hardware methods such as additional of layers of modulators, etc have been used. Selective data sampling of multi-channel energy is a software method which has been studied in this paper. The main purpose of this method, is obtaining the response of photon dosimetry at different energies. The response function of NaI(TL) 3”×3” detector for 0.411 MeV to 3 MeV gamma-rays has been simulated by using MCNPX code, and for calculating dose, the calibration coefficients were determined. Finally, the response energy of the detector has been drawn for photon dosimetry of the channels with multiple energy range. Results show that presented dosimety method has high level precision. 

Keywords


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