Thermoluminescence studies of CaSO4: Eu nanophosphor for electron dosimetry

Abstract

Sample of CaSO₄: Eu nanophosphor has been synthesized by chemical co-precipitation method and irradiated with 6.5 MeV electrons over the fluence range from 5×10¹⁴ to 4×10¹⁵ e/cm². The as-synthesized sample has been characterized by the XRD and TEM. The TEM image reveals that the nanocrystallites are in the form of nanorods of length 75 to 125 nm, with varying diameter of 10 to 20 nm. The XRD yields an average grain size ~15 nm, with hexagonal structure. The electron irradiated samples exhibit the thermoluminescence glow curve with a single peak at 162 °C. Moreover, the TL peak intensity increases with the increase in electron fluence and saturates beyond 3×10¹⁵ e/cm². Moreover, TL glow curves have been theoretically fitted using computerized glow curve deconvolution (CGCD) method to determine trapping parameters. The results indicate that CaSO₄: Eu can be used as a dosimeter for 6.5 MeV electrons over dose range from 15-80 kGy.