Neutron decay of the excitation-energy region up to 60 MeV, excited by heavy ion scattering. (I) 208Pb

The neutron decay of the continuum in Pb-208, excited by small-angle inelastic scattering of 84 MeV/nucleon O-17 ions in the range from 1.5-degrees, to 4.5-degrees, has been measured. Statistical decay was found to dominate the excitation-energy interval studied, up to 60 MeV. In the excitation-energy interval of about 10 to 30 MeV a distinct direct-decay component to the hold states in Pb-207 and a decay pattern resembling pre-equilibrium decay was observed. The angular correlation of the hole-state population suggests that in addition to the direct decay to the hole states in Pb-207, there is another, unidentified process populating the same states.