Boron nitride coatings for the enhanced detection of neutrons in CR-39

The neutron detection efficiency of Columbia Resin 39 (CR-39) nuclear track detectors was assessed for AmBe, 252Cf, and D-T (14 MeV) neutron source spectra. A boron nitride (BN) coating for CR-39 was developed to enhance the neutron detection efficiency by converting neutrons into energetic alpha particles through the well-known 10B (n,α)7Li reaction. Separate partially coated CR-39 pieces were exposed to each neutron source and subsequently analyzed under optical microscope and through large-area Scanning Electron Microscopy (SEM) imaging over the irradiated area. The detection efficiency (tracks per neutron) was evaluated for each source spectra under optical and scanning electron microscopes and with or without BN coating. This resulted in a comprehensive guide to neutron detection with various sources using CR-39.