Gamma-irradiation effects on track etching characteristics of polyester nuclear track detector

The effects of gamma irradiation in the dose range of 5-51 Mrad on the etching characteristics of a locally available Garware polyester film have been studied. The bulk etch rates at different doses were determined by the gravimetric method. The track etch rates at different doses were determined by measuring the track lengths. From the results, it is found that the bulk as well as the track etch rates increase with the increase in gamma dose. The increase in etch rates can be explained on the basis of scission of the detector due to gamma irradiation that enhances the dissolution rates. The sensitivity, which is the ratio of track etch rate to bulk etch rate, has been found to increase with gamma dose up to 11.5 Mrad doses and after that it decreases. From the measured bulk etch rates at different temperatures, the activation energies for bulk etching at different doses have also been determined.