Abstract: A directional fast neutron detector having superposed layers of a hydrogenous non-scintillating material for generating recoil protons, a non-hydrogenous scintillating material for generating scintillations, and a non-hydrogenous non-scintillating barrier material, in which the layers are placed in a specific order at regular intervals and the composition and thickness of the layers can be varied in order to alter the efficiency and sensitivity of the system. The detector exhibits both intrinsic and geometric directionality. The intrinsic directionality will depend primarily on the materials selected and the thicknesses of the individual layers, while the geometric directionality will depend primarily on the size and shape of detector. The detector of the invention provides a compact, relatively easy to use, directional neutron detector for use in locating and monitoring special nuclear materials and other sources of fast neutrons.

Abstract: A directional fast neutron detector having superposed layers of a hydrogenous non-scintillating material for generating recoil protons, a non-hydrogenous scintillating material for generating scintillations, and a non-hydrogenous non-scintillating barrier material, in which the layers are placed in a specific order at regular intervals and the composition and thickness of the layers can be varied in order to alter the efficiency and sensitivity of the system. The detector exhibits both intrinsic and geometric directionality. The intrinsic directionality will depend primarily on the materials selected and the thicknesses of the individual layers, while the geometric directionality will depend primarily on the size and shape of detector. The detector of the invention provides a compact, relatively easy to use, directional neutron detector for use in locating and monitoring special nuclear materials and other sources of fast neutrons.