A newly developed OSL dosimeter based on beryllium oxide: BeO:Na,Dy,Er

Abstract

This study aims to develop a high sensitivity Optically Stimulated Luminescence (OSL) dosimeter based on tissue-equivalent BeO:Na,Dy,Er ceramic (Zeff = 7.31) using the precipitation method. The material structure was confirmed by performing X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive X-ray (EDS) analyses. Thermoluminescence (TL), OSL, and X-ray luminescence (XL) techniques were used for the investigation of the luminescence properties. BeO:Na,Dy,Er has two TL peaks located at ~170 and 350 °C (at a heating rate of 2 °C/s) found to be associated with the OSL signals using the step annealing procedure. The OSL signals of newly developed BeO:Na,Dy,Er pellets were found highly sensitive to beta radiation and almost linear with a linearity coefficient of 1.03, i.e., described by a relation y=a+bx1.03at a range of 0.1–50 Gy. We investigated that the sensitivity of OSL from BeO:Na,Dy,Er pellets is the same after repeated exposure and reprocessing. Except for instability in short storage times, negligible long-term OSL signal fading was observed for up to three months at ambient temperature, in dark. In XL analyses, a broad band emission from 200 nm to 500 nm was observed at different dopant concentrations. The OSL characteristics of this material were found to be very encouraging and convenient for personal and medical dosimetry applications.