Single-Volume Neutron Scatter Camera for High-Efficiency Neutron Imaging and Spectroscopy

Abstract

Neutron detection provides an effective method to detect, locate, and characterize sources of interest to nuclear security applications. Current neutron imaging systems based on double-scatter kinematic reconstruction provide good signal vs. background discrimination and spectral capability, but suffer from poor sensitivity due to geometrical constraints. This weakness can be overcome if both neutron-proton scattering interactions are detected and resolved within one large contiguous active detector volume. We describe here a maximum likelihood approach to event reconstruction in a single-volume system with no optical segmentation and sensitivity to individual optical photons on the surfaces of the scintillator. We present results from a Geant4-based simulation establishing the feasibility of this single-volume neutron scatter camera concept given notional performance of existing photodetector and readout technologies.