The pre-dose effect in natural white mica (H2KAl3(SiO4)3)

A comprehensive study of the pre-dose effect was carried out for natural white mica. A pre-dose of 1 kGy of γ-radiation followed by thermal activation to 550 °C of fired mica (heated at 800 °C for 10 h) leads to a large increase in the TL sensitivity. The TL response to γ-rays of sensitized aliquots was found to be linear–sublinear while that of unsensitized aliquots was linear–superlinear referring specifically to graphs drawn on a linear–linear scale. The change in the TL sensitivity of mica was explained by using the recombination during heating model. This study is of importance in dating and retrospective dosimetry.