Characteristics of γ-ray-induced absorption bands in oxygen deficient silica

Characteristics of γ-ray-induced absorption spectra in oxygen deficient vitreous silica were investigated. The spectra were well fitted with five Gaussian absorption bands, the same bands as those reported before in x-ray- and excimer-laser-induced absorption spectra. Absorption intensity in oxygen deficient silica was much larger than those in silicas containing Si–OH or Si–Cl units. Creation mechanisms for radiation induced defects and role of terminal structures such as Si–OH and Si–Cl on resisting defect formation have been discussed.