Gamma radiation effects in capacitance of alpha alumina doped with rare earths

This paper presents the study of the gamma radiation influence on the dielectric properties of alpha-alumina doped with rare earths. The work deals with the possibility of determine the absorbed dose by capacitance measurements of the material. The samples were synthesized by sol–gel processes and Pechini, and best dopant concentration value was determined based on data from samples that supplied better behavior for luminescence dosimetry. A decrease in capacitance values with increasing radiation doses was experimentally verified. Ionization process produced excited charges carries, which are trapped in metastable states, which can change the characteristics of the dielectric alpha-alumina sample. - Highligths: ► We study the effect of gamma radiation on dieletric propertier in rare earths doped alumina. ► Increasing gamma radiation dose decreases the capacitance of all samples. ► We have discussed a model for reduction of capacitance with dose. ► We propose the use of the capacitance measurement on alumina samples for determining absorbed gamma radiation