Direction sensitive neutron detectors in near field measurements

Experimental work performed in the area of neutron detector development at the Remote Sensing Laboratory-Andrews Operations (RSL-AO) sponsored by the U.S. Department of Energy, National Nuclear Security Administration (NNSA) in recent months is presented in this article. Ten pressurized He-3 tubes with an inch of annular polyethylene moderator around them are arranged to make an isosceles triangle with three fold symmetry. MCNPX simulation code has been used to obtain the angular response function of the detector array using a bare Cf-252 source. The neutron counts profile shows possibility of determining the angle of a near - field neutron source with adequate angular resolution for emergency response.