Evidence of continuous trap distribution in the glow curve of a Brown microcline

Abstract

The formidable task of determining a mathematical form of the trap distribution in a solid has been solved for the case of an unusually broad thermoluminescence (TL) glow peak of a Brown microcline (feldspar, triclinic form of KAlSi3O8). An exponential distribution of traps gives the best fit to the experimental glow peak. Five TL glow peaks of the Brown microcline which was previously irradiated with γ-rays and then subjected to fading at room temperature are numerically analyzed using the exponential distribution model of traps. The dependence of the best-fit trap parameters are found: (1) the width and the characteristic depth of the trap distribution; (2) the rates of recombination and retrapping of the released electrons from the traps; and (3) the concentration of thermally disconnected traps on the fading time. These trap parameters show a clear dependence on the time of fading. The procedure of the TL analysis using a continuous trap distribution is also reported in detail.