Elastic and Inelastic Scattering of Fast Neutrons from 6Li and 7Li

摘要

The differential elastic and inelastic neutron scattering cross sections of 6Li and 7Li have been measured at incident neutron energies of 4.83, 5.74 and 7.5 MeV for 6Li and at energies of 3.35, 4.83, 5.74, and 75. MeV for 7Li Scattered neutrons and gamma rays were observed independently. The cross sections were measured with a neutron time-of-flight spectrometer relative to the well-known cross section for neutron scattering from hydrogen. The gamma-ray spectra were measured with a NaI(Tl) spectrometer using time-of-flight techniques to elimi¬nate the neutron background. The 2.l84-MeV state in 6 Li was excited by neutron inelastic scattering. The 3.56-MeV state in Li was not observed in either the neutron or gamma-ray studies. Scattered neutrons from the 0.478-MeV state in 7Li were resolved at both 3.35 and 4.83 MeV. Scattered neutrons from the 4.63MeV state in 7Li were observed at incident neutron energies of 5.74 and 7.5 MeV. A continuum of neutrons due to three-particle breakup was observed for both 6Li and 7Li at 4.83, 5.74, and 7.5 MeV.