Dependence of Thermoluminescence Response of CaSO4:Dy and CaSO4:Tm on Grain Size and Activator Concentration

Abstract The influence of several factors on the thermoluminescence (TL) sensitivity and the shape of the glow curves of CaSO4:Dy and CaSO4:Tm phosphors have been investigated. The factors investigated are: quality of starting materials, activator concentration and grain size. The TL sensitivity and the height of low temperature peaks (LTP) are influenced by the impurity of the starting chemical (CaSO4.2H2O) and the concentration of activators (Dy and Tm). Sensitive CaSO4:Dy and CaSO4:Tm phosphors having small LTP were prepared by using purified starting chemical (CaSO4.2H2O). The measurement data from our samples were compared with the results of samples prepared in different laboratories.