Spectrally resolved thermoluminescence of pure potassium chloride crystals

Alkali halides are wide band gap dielectric materials, which are very important for luminescence dosimetry. Nevertheless, only some of them were studied comprehensively. Potassium chloride (KCl) is alkali halide material, which shows pronounced thermoluminescence (TL) and optically stimulated luminescence (OSL). The material occurs also in natural mineral form as sylvite (or sylvine). This paper presents results of spectrally resolved thermoluminescence (SR-TL) measurements of pure KCl crystals in temperature range 300-550 K for various doses of beta irradiation. Four emission bands were found relating to different recombination centers in this material. TL curves relating to these centers have different shape. It indicates that recombination centers are not filled concurrently.