The dependence on the excitation dose of the maximum thermoluminescence intensity as well as of the peak temperature are investigated theoretically. It is shown that certain irregularities of the dose dependences can be explained by assuming the existence of a trapping level, the transition into which competes with the retrapping and recombination of the free carriers. By numerical solution of the appropriate equations, it is demonstrated that the maximum thermoluminescence intensity may depend superlinearly on the excitation dose. The power of the dose dependence was found to be 2 under certain circumstances at low doses, and reached even higher values before saturation of the competing level. The maximum temperature sometimes behaved in an unusual way; namely, it increased with increasing dose. The relation between the area under a glow peak and its maximum intensity is also studied; it is shown that the latter can usually serve as a measure for the former. This finding is of practical importance, especially in thermoluminescent dosimetry, since the evaluation of the maximum intensity is obviously more convenient than that of the area.

In the applications of thermoluminescence (TL) in dosimetry and archaeological and geological dating, a desirable dose dependence of TL intensity is a monotonically increasing function, preferably linear. It is well known that in many dosimetric materials, nonlinear dependence is observed. This may include a superlinear dependence at low doses and/or sublinear dose dependence at higher doses, where the TL intensity approaches saturation. In quite a number of materials, non-monotonic dose dependence has been observed, namely, the TL intensity reached a maximum value at a certain dose and decreased at higher doses. This effect is sometimes ascribed to 'radiation damage' in the literature. In the present work we show, both quasi-analytically and by using numerical simulation, that such dose dependence may result from a simple energy level scheme of at least one kind of trapping state and two kinds of recombination centres. One does not necessarily have to assume a destruction of trapping states or recombination centres at high doses. Instead, the main concept involved is that of competition which takes place both at the excitation stage and the readout stage during the heating of the sample. This may explain the fact that the phenomenon in question, although very often ignored, is rather common. Cases are identified in which competition during excitation dominates, and others in which competition during read-out dominates.

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Constant temperature hot gas readers are widely employed in thermoluminescence dosimetry. In such readers the sample is heated according to an exponential heating function. The single glow-peak shape derived under this heating condition is not described by the TL kinetics equation corresponding to a linear heating rate. In the present work TL kinetics expressions, for first and general order kinetics, describing single glow-peak shapes under an exponential heating function are derived. All expressions were modified from their original form of I (n 0 , E, s, b, T) into I (I m , E, T m , b, T) in order to become more efficient for glow-curve deconvolution analysis. The efficiency of all algorithms was extensively tested using synthetic glow-peaks.

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