Investigation of factors which lead to the background in the measurement of nitrogen by IVNAA

Abstract
A major problem in the measurement of nitrogen in the body by in vivo neutron activation analysis (IVNAA) is the size of the background. Investigations show that random summing of gamma rays in the range 4-7 MeV is a major contributor. By direct comparison, 252Cf is shown to be a better neutron source than Pu-Be in this regard. Data are presented on the contribution to the background of water and chloride in the body.