Development of bismuth self-powered detector

Self-powered detectors have been developed with bismuth (2 mm diameter×6.4 mm) and platinum (2 mm diameter ×5 mm) emitters. Tests at a 60Co irradiation facility in 0.125 MR/h (484.5 MC/kg/h) gamma field showed that the gamma sensitivity of the two detectors is 0.121 fA/R/h (0.468 pA/C/kg/h) and 0.17 fA/R/h (0.658 pA/C/kg/h). When tested in the core location in Apsara Swimming Pool reactor the current from Bi detector was assumed to be totally gamma-induced. This information was used to derive the neutron-induced component of the Pt detector in which 55% of the total signal was gamma-induced. The neutron sensitivity was found to be 0.54×10−21 A/nv.