Neutron-Induced Gamma-Ray Production in Lead-208 for Incident-Neutron Energies Between 4.9 and 8.0 MeV and in Bismuth-209 for an Incident-Neutron Energy of 5.4 MeV

Interactions of neutrons with ²⁰⁸Pb have been studied by measuring photon production cross sections. Gamma-ray spectra were obtained at incidentneutron energies of 4.9, 5.4, 6.4, 6.95, 7.45, and 8.0 MeV with a gamma-ray detector system utilizing a 48-cm³ Ge(Li) detector. Nearly monoenergetic neutrons were obtained from the D(d, n) reaction using deuterons obtained from the (pulsed) Oak Ridge National Laboratory 5-MV Van de Graaff accelerator. Time-of-flight was used to discriminate against pulses due to neutrons and background radiation. Extracted differential and total inelastic cross sections have been compared with previous measurements and with data from the ENDF/B evaluation with generally satisfactory results. New information on the level structure of ²⁰⁸Pb is reported. Data were also obtained at E_n = 5.4 MeV for a sample of natural bismuth, and new information on the level structure of ²⁰⁹Bi was obtained. Differential gamma-ray production cross sections were obtained, and the total inelastic cross section at E_n = 5.4 MeV was deduced from these data.