Radiation damage and its effect on the thermoluminescence properties of minerals sphene and epidote

The paper describes the effects of both natural and artificially induced damage in sphene and epidote crystals, as monitored by their fossil fission track density (FFTD) or produced by different fluences of 30 MeV 4He particles from a cyclotron, on the thermoluminescence (TL) of these crystals. Radiation damage in both minerals has been found to cause an adverse effect on their TL properties. An inverse correlation, for instance, has been found between the amount of artificially induced α-damage and the TL sensitivity. However, when FFTD was measured to gauge the degree of damage in various samples of these minerals during their geological history, no such correlation was observed. An attempt is made to explain the possible reason for this lack of correlation between the FFTD and the TL sensitivity. (author)