Evaluation of energy responses for neutron dose-equivalent meters made in Japan

Saegusa, Jun; Yoshizawa, Michio ; Tanimura, Yoshihiko  ; Yoshida, Makoto; Yamano, Toshiya*; Nakaoka, Hiroshi*

Energy responses of three types of Japanese rem counters were evaluated by Monte Carlo simulations and measurements. The energy responses for thermal neutrons, monoenergetic neutrons with energies up to 15.2 MeV were evaluated as well as for neutrons from such radionuclide sources as Cf. The calculated results were corroborated with the measured ones. Angular dependence of the response and dose equivalent response was also evaluated. As a result, the reliable energy responses were obtained by careful simulations of the proportional counter, moderator and absorber of the rem counters. Furthermore, discussions were made about the relationship between pressure of counting gas and sensitivity of the rem counter. By using the obtained responses, relations of predicted readings of the rem counters and true dose equivalent were studied for various workplace spectra.