Energy Levels of Sc48 from a Study of Neutrons and Gamma Rays Emitted by the Ca48(p,nγ)Sc48 Reaction

Abstract

Energy levels of ${\mathrm{Sc}}^{48}$ up to 2.5 MeV excitation have been studied by observation of neutrons and gamma rays produced in the ${\mathrm{Ca}}^{48}(p,n\gamma ){\mathrm{Sc}}^{48}$ reaction. Analysis of neutron spectra obtained at $E_p=3.250\mathrm{}$ MeV with a ${\mathrm{He}}^3$-filled proportional counter, and of gamma-ray spectra obtained at various proton bombarding energies with a lithium-drifted germanium gamma-ray detector, shows that the ${\mathrm{Ca}}^{48}\mathrm{}(p,n)\mathrm{}{\mathrm{Sc}}^{48}$ reaction does not populate the ${\mathrm{Sc}}^{48}$ ground state directly. The ground-state-reaction $Q$ value is found to be -529±10 keV, which implies a mass excess of -44240±14 keV for ${\mathrm{Ca}}^{48}$. Excited states of ${\mathrm{Sc}}^{48}$ have been established at 131±2, 253±2, 624±3, 1144±3, 1406±3, 2192±3, 2277±3, and 2519±5 keV. Possible spin assignments have been deduced from the gamma-ray branching ratios.