SENSITIZATION OF THERMOLUMINESCENCE IN SYNTHETIC QUARTZ - HEAT-TREATMENT AND RADIATION EFFECTS

Changes in the sensitivity to beta dose of the 100-degrees-C TL peak in synthetic quartz powder have been studied. While the emission in the visible range (approximately 450 nm) was separately measured, the sensitivity increased substantially by high dose (approximately 100 Gy) irradiation. This sensitivity was found to be reduced by repeated heatings to about 300-degrees-C, followed by 8 Gy (test dose) irradiations. The reduction of sensitivity was down to a certain equilibrium value. Applying the test dose followed by heating to the same temperature repeatedly to an unirradiated portion of the same sample, caused an increase in the sensitivity which reached an equilibrium after several such cycles; usually the same equilibrium as before. A qualitative model, consistent with previously known facts concerning synthetic quartz is given. The possibility that remnants of this effect occur in previously fired samples may explain some anomalous results in the pre-dose effect of sensitization observed in natural quartz.