Discrete Gamma Radiation in Interaction of 14.9-MeV Neutrons with Natural Lead

The gamma radiation in the interaction of 14.9-MeV neutrons with a natural lead sample is investigated by the total gamma radiation measurement technique (TGRM). Forty-nine prompt gamma lines and 8 delayed gamma lines, which come from (n,n^') and (n,2n) reactions of ²⁰⁶Pb, ²⁰⁷Pb, and ²⁰⁸Pb, are identified, and their differential production cross sections at 55, 90, and 140 deg are determined. Six mixed gamma-ray peaks are separated, and the production data of the prompt and delayed components are given separately. The production cross sections of three isomeric states (1013.7 keV, (13/2)⁺, 5.5 ms in ^205mPb; 2200.2 keV, 7^-, 124s in ^206mPb; and 1633.3 keV, (13/2)⁺, 0.81s in ^207mPb) are accurately determined. They are in good agreement with some recent experimental and theoretical results. This is the most successful example of applying TGRM in an (n,x) experimental study following after the aluminum study.