Proton elastic and inelastic scattering at 0.8 GeV fromC12,13andPb208

Abstract

Angular distributions for the elastic and inelastic scattering of 0.8 GeV protons from ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$, and ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ have been measured. Reported are data for the ground, 4.4 MeV 2+, 7.6 MeV 0+, 9.6 MeV $3^{-}$, and 14.1 MeV 4+ states of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$; the ground, 3.1 MeV $\frac{1}{2^{+}}$, 3.7 MeV $\frac{3}{2^{-}}$, 6.9 MeV $\frac{5}{2^{+}}$, 7.6 MeV $\frac{5}{2^{-}}$, and 11.9 MeV (?) states of ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$; and the ground, 2.6 MeV $3^{-}$, and 3.2 MeV $5^{-}$ states of ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$. Analyses of the elastic angular distributions are made using the partial wave formalism and the Kerman-McManus-Thaler approach to the nucleon-nucleus optical potential; a realistic spin-orbit term is included. The inelastic transitions are analyzed within the framework of the distorted-wave Born-approximation, using transition strengths consistent with previous low-energy studies of inelastic scattering. A simple single-particle-plus-excited-core model is used for ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$. In terms of this analysis, an assignment of $J^{\pi }={(\frac{5}{2}, \frac{7}{2})}^{+}$ is made for the 11.9 MeV state in ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$.