Optical responses of a copper-activated sol-gel silica glass under low-dose and low-dose rate X-ray exposures

Ionic copper-doped silica glasses are attractive materials for radiation detection and dosimetry based on radioluminescence (RL) and optically stimulated luminescence (OSL). We characterized the optical responses, under X-rays, of a Cu+-doped silica glass rod prepared via the sol-gel technique and spliced to transport pure silica optical fibers. Both the low-dose and the low-dose rate regimes were specially investigated at room temperature. RL and photoluminescence (PL) measurements confirmed that the Cu+ ions are the luminescent centers of interest for the targeted applications. RL dose rate response dependence shows a linear behavior from 260 μGy(SiO2)/s up to 23 mGy(SiO2)/s, allowing the monitoring of the dose rate evolutions during an irradiation run. The OSL response also linearly depends on the dose from 42 mGy(SiO2) to 200 Gy(SiO2), enabling a precise dose measurement shortly after the irradiation. The presented results confirm the potentialities of this material to monitor ionizing radiations in harsh environments.