Characterization of a PN3 personal neutron dosimeter based on (n,α) reaction

Abstract

This study describes a new methodology for characterizing the sensitivity of personal neutron dose-equivalent dosimeters consisting of a PN3 (trade name of the CR-39 type) nuclear track detector coupled with a natural boron converter BN1 (20% 10B, 80% 11B) and enriched boron converter 10B (99% 10B). Both dosimeters (converter + detector) were mounted in an ISO water-filled phantom and were simultaneously irradiated in terms of personal dose equivalent Hp(10) ranging between 1 and 4 mSv under standard neutron radiation fields generated by (252Cf + D2O) and (252Cf + D2O)/Cd) sources. After irradiation, the latent tracks produced by alpha particles were revealed through a chemical solution. The optimum etching conditions (6.25 N, 70 °C for 7 h) used, were performed for an initial in-depth study. The response of the dosimeter was given by the ratio of the average track density obtained by subtracting the tracks due to the 252Cf + D2O and (252Cf + D2O)/Cd sources to the dose equivalent. The calibration factor was found to be 2826 ± 17 tracks.cm−2.mSv−1. The sensitivity of the dosimeter was observed to be increased significantly using a converter enriched in 10B (99% 10B).

Keywords

• Thermal neutron
• PN3 detector
• Dosimetry
• Etching condition