Calibration of a passive rem counter with monoenergetic neutrons

Rem-Counters are widely used in radiation protection practice for environmental neutron detection. They are usually based on both an active and a passive thermal neutron detector surrounded by a hydrogenate moderator designed to obtain a response function as close as possible to the H*(10) curve. Inclusion of high Z material is also used to extend the response function up to 1 GeV of neutron energy. Recently a dual detector Rem-Counter, both active and passive, was proposed by Agosteo et al. (2010). The present paper focuses on the passive version that is based on a CR-39 track detector coupled to an enriched 10 B converter. A technique was developed for the track analysis based on the measurement of the mean LETof the charged particles produced by the neutron reaction on 10B that has proven to be verye ffective in the background reduction. Moreover the simulated response function of the Rem-Counterwas compared with the experimental results obtained with irradiations carried out with mono-energetic neutron beams, showing a quite good agreement.