The electron spin resonance measurement of irradiation defects in neutron-irradiated vitreous silica was performed to study the effects of the OH content, neutron fluence, and post-irradiation isochronal anneal to 873K. Together with the usual paramagnetic states of E' centers, non-bridging O hole centers (NBOHCs), and peroxy radicals (PORs), some new states were observed in the electron spin resonance spectra. The principal-axis g-values of these states lay in the range of 2.0 to 2.2, which were typical of O2- ions in solids. Considering these new defects, the observed effects of the OH content, neutron fluence, and post-irradiation isochronal anneal were discussed to obtain some details of the reaction mechanism of the irradiation defects.

Electron Spin Resonance Measurement of Irradiation Defects in Vitreous Silica Irradiated with Neutrons. K.Moritani, I.Takagi, H.Moriyama: Journal of Nuclear Materials, 2004, 325[2-3], 169-73