Abstract:
Three materials wherein suitable proportion of isotope enriched
10B powder, 1,2-ethylene dichloride and formvar resin were blended to make
10B neutron sensitive coating by oneself. A new type proportional counter that coated with
10B neutron sensitive coating was made. Furthermore, in order to increase the character and quality of the neutron detector, a set of 14 annulus epoxy sheets which were sided with
10B film were placed in the tube. A series performance tests were done by
241Am-Be neutron source. The tests of 3.7×10
9 Bq
241Am-Be neutron source show that the plateau length of detector is 150 V from 750 V to 900 V, while the plateau slope is 8.2%/100 V. When the working voltage is 800 V, the count rate of new type boron-coating proportional counter is 50 s
-1. The level of sensitivity is 0.71 cm
2. Compared with the detector only coated with
10B film in the inner walls of detector, neutron sensitity area of the new detector increases to 3.15 times. The results show that the plateau length increases from 80 V to 150 V, and the plateau slope is improved from 12.4%/100 V to 7.58%/100 V, while the neutron sensitivity increases to 2.63 times. Using Geant4 software based on Monte Carlo method, this paper presented the response and detection efficiency of new type boron-coating proportional counter, which was covered with 55 mm×250 mm cylinder high density polyethylene moderator material. The simulation results of Geant4 are in agreement with the results of
241Am-Be neutron source experiment.It shows the reliability of simulation application.