EPR Dosimetric Potential of Ammonium Oxalate Monohydrate in Radiation Technology

This study aims to examine the dosimetric properties of the ammonium oxalate monohydrate (COONH4)(2)H2O irradiated by Co-60 gamma-rays. The EPR spectra of ammonium oxalate have the spectroscopic splitting g-factors of 2.0095 and 2.0047. Results indicate that the dose-response curves have a good linearity in the range between 10 and 1000Gy. Slight sub-linearity has been found in high dose region up to 25 kGy. The effects of temperature and humidity on the EPR signal amplitude of the irradiated samples were studied. Stability of the irradiation rods upon storage (signal fading) was also investigated. Energy dependence has been found within 38% at the range below 100 keV. The dosimeter displayed an increasing response by approximately 4% over the energy range 6-10 MeV. The overall uncertainty of this dosimetry system is 4.64% (sigma 2) in low dose range and 3.67% for the high dose range.