A Direction Sensitive Neutron Detector

The threat of nuclear terrorism presents an increasingly urgent and difficult challenge to the United States in the 21^st Century. New technologies with improved sensitivity will be needed to identify hidden nuclear weapons in order to protect the United States from this threat. This paper describes a detector under development that will measure the direction and energy of recoiling nuclei produced in collisions with neutrons emitted by spontaneous fission from plutonium warheads. Such a detector will have improved sensitivity compared to other neutron detectors due to its ability to determine the direction of approach of the neutrons, thereby reducing significantly the backgrounds due to cosmic ray neutrons.