PROPOSAL OF NEUTRON DOSIMETER BASED ON A DIFFERENTIAL STRUCTURE

Theoretical and experimental knowledge of neutron converter (boron implanted polyethylene) for thermal and fast neutron and its use with etched track detector were previously obtained in our laboratory. These results allow us to propose a neutron dosimetry system based on a differential method. It consists in irradiating two areas of the detector, one covered by a converter (neutron-charged particles), the other uncovered, and in substracting the responses. Here we generalize this principle, by taking into account the albedo and transmission effects in neutron fields(thermal, intermediate, fast) and we choose a neutron converter with the same dosimetric efficiency for thermal and fast neutrons (< 3MeV). In this paper we propose, for routine use of this dosimetric structure, to work on four areas so that it is possible to obtain the contribution of each kind of neutrons and through a systematic analysis of the response an exploitation of the system in three steps in order to optimize reading time.