Monitoring fast neutron flux inside spent reactor fuel by CR-39 detector

摘要

A model experiment was carried out by CR-39 detectors using Cf-252 neutron sources in an intense gamma field obtained by Co-60 irradiation. Based on this calibration and introducing corrections due to the angle, gamma -dose, and etching time dependences of the detector response, fast neutron flux inside spent fuel assemblies was found to be in the range of 10(2)-10(6) n cm(-2) s(-1), depending on burnup and cooling time. The effect of adjacent assemblies can decrease substantially, if the detector surface is perpendicular to the axis of the fuel assembly. (C) 2001 Elsevier Science Ltd. All rights reserved. [References: 7]