Electron spin resonance measurement of irradiation defects produced in quartz crystal

The electron spin resonance (ESR) measurement of irradiation defects in ion beam or neutron irradiated quartz crystal was performed. In each case, the formation of the E′ centers and peroxy radicals (PORs) was observed but that of the non-bridging oxygen hole center (NBOHC) was hardly observed. The spin densities of these defects were measured as a function of the dpa value and postirradiation isochronal annealing temperature. By comparing the obtained results with those of vitreous silica, the production and reaction mechanisms in quartz crystal were discussed.