Sensitization effects on the tracks of neutron irradiated CR-39 detectors treated with CO2 under pressures greater than 0.6 MPa

Abstract

An extensive investigation was done of the sensitization effects of carbon dioxide pre-etching treatments on the tracks of CR-39 detectors exposed to fast neutrons. The detectors were irradiated with an 241AmBe neutron source in a low-scatter laboratory, delivering a personal dose equivalent Hp(10) of 1 mSv. Prior to the chemical etching, the detectors were treated in carbon dioxide at partial pressures ranging from 0.6 to 2.4 MPa for times ranging from 6 to 144 h. By examining treatments under pressures greater than 0.6 MPa, our goal was understanding the correlation between detector response and treatment time and optimizing the conditions for practical applications of CR-39 detectors in neutron dosimetry and spectrometry. From the analysis of the track size distribution for each treatment condition, we found a consistent trend regarding the increasing number of detected tracks. Moreover, by correlating the integral of these track distribution curves with the treatment time, we found a linear increase in detector sensitivity for all the investigated pressures, the first time such behavior is reported. This could help a dosimetry laboratory optimizing and adjusting the treatment time, while also improving the detector sensitivity.