Neutron and proton dynamics of Ca48 levels and -ray decays from neutron inelastic scattering

Differential cross sections were measured for the Ca48(n,n) reactions at incident energies between 4.8 and 8.0 MeV. Excitation energies, spins, level lifetimes, -ray branching ratios, and -ray production cross sections were determined. Members of the doublet at 4.50 MeV are clearly identified and assigned spins of 4+ and 3-. Inelastic neutron scattering cross sections were inferred from the -ray branching ratios and production cross sections. The inferred cross sections are in excellent agreement with those measured in a separate neutron detection experiment, and with a recent vibrational model coupled-channels analysis of the Ca48(n,n) data. Comparison of level excitations produced by neutrons and other hadrons with electomagnetic strengths shows very different mixtures of neutron and proton particle-hole amplitudes for different levels.