Radiation Protection Dosimetry 20:77-80 (1987)
© 1987 Oxford University Press
A Cubical Fast Neutron Dosemeter Based on Electrochemically Etched CR-39 Detectors with Polymeric Front Radiators
The problem of angular dependence of the response of electrochemically etched CR-39 fast neutron dosemeters can be minimised by averaging the response of three mutually perpendicular detector assemblies. To achieve this, CR-39 detectors, together with optimised front radiator stacks (each consisting of a 150 µm thick polyimide foil followed by 800 µm polystyrene and 3 mm polyethylene), have been attached to three adjacent sides of a supporting cube made of perspex (of side ~2.5 cm). These cubical detector assemblies have been irradiated with neutrons of several discrete energies, ranging from 0.1 to 19 MeV, and employing various cube orientations with respect to the neutron beam axis. The dose equivalent response of the detectors has been studied as a function of cube orientation, and the experimentally observed values are compared with theoretical predictions. By using the above mentioned radiator stack, a reasonably energy independent dose equivalent response has been achieved. The direction dependence has also, by this means, been reduced to less than ±25%.