NEUTRON TISSUE DOSE AT LARGE DISTANCES FROM AN ELEVATED UNSHIELDED REACTOR

The neutron tissue dose at large distances from a fission source was studied by using a water-filled phantom and four different detectors: a BF/sub 3/ counter, a polyethylenelined ethylene-filled proportional counter, indium foils, and nuclear emulsions. The source of fission neutrons was the ORNL Health Physics Research Reactor which was attached to a hoist which was in turn installed on a 1530-foot tower. The reactor could be operated at any elevation from 27 to 1500 ft. The phantom studies were made at horizontal distances from 250 to 1500 yards from the tower. Dose contributions from recoil protons H/sup 1/ (n, gamma )D/sup 2/ and N/sup 14/(n,p)C/sup 1 reactions are considered. (auth)