Fast neutron scattering on even isotopes of Ni

Both differential and integral cross sections of 1.5, 2.0, 2.5, 3.0 MeV neutron elastic and inelastic scattering on sup(58,60,62,64)Ni nuclei were measured between 20 deg and 150 deg using the time-of-flight method and a T(p,n)3He neutron source. Corresponding angular distributions and excitation functions have been analyzed in terms of the optical model with averaged nuclear potentail parameters and and in terms of the statistical model with and without account of level width fluctuations. Theoretical calculations describe satisfactorily the experimental data for the elastic scattering. The statistical model depicts well both differential and integral cross sections for the inelastic scattering, the account of level width fluctuations resulting in a significant improvement of the agreement. The basic mechanism of the inelastic scattering is concluded to be a compound-nucleus reaction