Photostimulated thermoluminescence of radiation-coloured quartz glasses

Problems of radiation-optical stability of fiber light pipes produced on the basis of pure quartz glasses have been studied. The glasses were irradiated by Co60 gamma-quanta exposure dose rate approximately 700 rad/s) at room temperature or liquid nitrogen temperature. In γ-irradiated quartz glasses cooled down to 77 K, the effect of photostimulated thermoluminescence (PTL) has been oOserved. Using the PTL method an attempt to identify two photostimulated peaks at 130-140 and 260-290 K in all the glasses investigated has succeeded. The peaks are assigned to the same family according to the sign of a common charge carrier. In glasses of KSG type one more photostimulated TL peak at 110-120 K is observed that is related to the decomposition of atomic hydrogen centers and attributed to another family of TL peaks. It is established, that, during heating of the irradiated quartz glasses, the charge carriers, liberated out of deep traps, before recombination pass through intermediate states, conforming to TL peaks at 130-140 and 260-290 K i.e. the process of thermoluminescence has a step-wise character