DOSE-RATE EFFECT IN CALCITE

A study of the evolution of thermoluminescence versus gamma and beta i rradiation with a different dose rate, has been made for calcite sampl es. Evolution of TL signals in both irradiation types is initially sup ralinear but then becomes linear up to at least 7 kGy. Moreover, if a set of samples previously gamma-irradiated at a fixed dose rate for a long time are later beta-irradiated, the relative populations of creat ed centers seems to be characteristic of the last irradiation. The rev erse effect has also been observed. (C) 1998 Elsevier Science B.V. All rights reserved.