Effects of temperature during the irradiation of calcium carbonate

• Gamma irradiation of CaCO3 at different doses and temperatures was studied.
• High radiation induces the formation of free radicals in solid calcium carbonate.
• Gamma irradiation of CaCO3 produced a composite spectra measured by EPR.
• There is a strong effect on the radicals formed as a function of temperature.

Calcium carbonate received gamma irradiation at different doses (0–309 kGy) and temperature regimes (77–298 K) to study the effects of irradiation temperature. The changes were followed by EPR spectroscopy. We observed the formation of a composite EPR spectrum, even at low radiation doses and temperature. There was a strong effect on the evaluation of the radicals formed as a function of irradiation temperature, probably due to the diffusion in the frozen powder and the recombination of some radicals at room temperature.