Gamma-radiation-induced conductivity in glasses

Determinations of the changes in the electrical conductivities of several different types of glasses during gamma irradiation have been made. Fused silica, aluminosilicate, borosilicate, and alkali lead-silicate glasses were among the types examined. The fused silica exhibited the most pronounced change in conductivity. For example, at a dose rate of 10rad(H2O)/s, the conductivity at room temperature exceeds 10¿15mho/cm. This is to be contrasted with the value of approximately 10¿20mho/cm, taken from data extrapolated to room temperature for the same glass in the absence of radiation. The effects of dose and dose rate on the conductivity of fused silica were also investigated as a function of temperature. Results are analysed on the basis of Rose´s theory of photoconductivity.