The effect of rare earth doping on the glow peak positions of LiNaSO4

Thermoluminescence of the rare earths (Ho, Tb, Gd, Sm, Ce or La) doped LiNaSO4 and irradiated at room temperature was studied in the temperature range 300-673 K. The glow curves of this material consistently illustrate the presence of two groups of glow peaks that behave differently. The first group occurs in the temperature range 350-450 K, and the individual peaks occur at the same temperature for all dopants. The second group (500-650 K), which contains the dosimetric peak, is noted to move in temperature with the size of the RE dopants. The switch in behavior of the glow peaks is attributed to a possible phase transition of the host material near 500 K. Additionally, the relatively simple glow curve, low fading and the presence of the dosimetric peak at high temperatures with 80-100% of the total glow-curve area contained within the complex above 500 K make the material suitable for radiation dosimetry at high temperature.