Intrinsic efficiency of CaSO4:Dy to electron beams

Abstract

The intrinsic efficiency of CaSO4 :Dy thermoluminescent dosimeters, developed by Instituto de Pesquisas Energéticas e Nucleares – IPEN was calculated for 3.43, 5.48, 8.27, 11.67 and 15.42 MeV clinical electron beams at their depth of maximum ionization in polymethyl methacrylate (PMMA), SW Solid Water and standard water phantoms. The sensitivity, varying from 14.6 ± 0.3 mC.Gy-1 (11.67 MeV, PMMA) to 19.6 ± 0.5 mC.Gy-1 (15.42 MeV, water), the reproducibility of the TL response, better than 2.4%, and the TL response as a function of the dose, linear between 0.01 and 3.25 Gy, were also evaluated. The intrinsic efficiency of 0.0342 ± 0.0021 % indicates that CaSO4 :Dy dosimeters can be applied to the radiation protection for high energy electron beams generated by linear accelerators.