Design of a high efficiency boron-loaded plastic scintillation detector for a wide spectrum of neutrons

For improving detection efficiency of 0.02-0.25 MeV neutrons by boron-loaded plastic scintillation detector (BLPSD), surrounding the scintillator with polyethylene moderator is feasible way. In this paper, the detection efficiency of a BLPSD with front and side PE moderators of different thicknesses is simulated by MCNP code, and the thickness-dependant detection efficiencies are given. The results show the side PE moderator of 80 mm thick increases the BLPSD detection efficiency of 0.02-0.25 MeV neutrons by a factor of about, but the front PE moderator decreases the detection efficiency. Finally, the design structure of BLPSD surrounded by side PE moderator can realize high detection efficiency for a wide spectrum is proved.