A comparison of gamma and X-radiation effects on high quality quartz oscillator crystals

Experiments have shown high quality quartz oscillator crystals to exhibit a much greater fractional frequency change when irradiated with X-rays, with photon energies less than 100 keV, than when exposed to Co60 gamma radiation at the same dose rate. In both cases, the shift is negative, dose rate dependent, and recovers rapidly once irradiation ceases. The probable causes of these effects are temperature and electric charge gradients resulting from build up and dose enhancement processes.<>