The possibility of using the DKS-AT1123 dosimeter for radiation monitoring of medical electron accelerators with an energy of more than 10 MeV

Abstract

The X-ray and gamma radiation dosimeter DKS-AT1123, designed for dosimetry of pulsed photon 

radiation with an energy of up to 10 MeV, is widely used for radiation monitoring of medical electron accelerators. Since the maximum energy of the bremsstrahlung radiation of medical electron accelerators can significantly exceed this value, the main purpose of this work was to calculate correction factors to compensate for the energy dependence of the sensitivity of the DKS-AT1123 dosimeter. It makes possible to obtain correct results of radiation monitoring of medical electron accelerators with an electron energy of up to 30 MeV. Materials and Methods: For this purpose, the authors calculated the energy spectra of bremsstrahlung radiation generated by electrons with energies of 10, 15, 20, 25 and 30 MeV behind concrete shield with a thickness of 0.5, 1.0, 1.5, and 2.0 m. Calculations were performed using the Monte Carlo method. Using the data obtained, correction coefficients to compensate for the energy dependence of the DKS-AT1123 dosimeter for all considered electron energies and concrete shield thicknesses were calculated. Results and Discussion: An analysis of the results showed that the correction factors are weakly dependent on the thickness of the concrete shield. For thicknesses from 0.5 to 2.0 m, the differences in the correction coefficients do not exceed 8 %. Numerical values of correction coefficients equal to 1.29; 1.44; 1.50; 1.56 and 1.60 were obtained for the maximum bremsstrahlung radiation energy of 10, 15, 20, 25 and 30 MeV, respectively. Conclusion: The use of these correction factors makes it possible to conduct radiation monitoring of medical electron accelerators using the DKS-AT1123 dosimeter.