High spin states in 208Pb.

Abstract

Proton cross sections for $^{208}\mathrm{Pb}$ have been measured for elastic and inelastic scattering to the ${12}^{+}$, 6.10 MeV, ${12}_{1}^{\mathrm{\ensuremath{-}}}$, 6.43 MeV, ${12}_{2}^{\mathrm{\ensuremath{-}}}$, 7.06 MeV, and ${14}^{\mathrm{\ensuremath{-}}}$, 6.74 MeV states at ${E}_{\mathrm{p}=318}$ MeV. We analyze the inelastic transitions in the distorted wave impulse approximation and use the previously published electron scattering results to constrain the wave functions in the unnatural parity calculations. A ${13}^{\mathrm{\ensuremath{-}}}$ state is discussed as an unresolved ``contaminant'' to the ${12}_{1}^{\mathrm{\ensuremath{-}}}$, 6.43 MeV state. Mixing between the ${12}^{\mathrm{\ensuremath{-}}}$ neutron and proton particle-hole configurations is found to reduce substantially the differences reported previously in observed proton and electron quenching factors. This results in greater quenching for the ${12}_{2}^{\mathrm{\ensuremath{-}}}$, 7.06 MeV state, and less quenching for the ${12}_{1}^{\mathrm{\ensuremath{-}}}$, 6.43 MeV state than was previously reported in (e,e') analyses.