Interference Between Coulomb and Nuclear Excitation in the Inelastic Scattering ofB11Ions fromPb208

Abstract

The elastic and inelastic scattering of 72.2-MeV ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ ions from ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ were studied. The angular distributions for transitions to the $3^{-}$, $5^{-}$, $2^{+}$, and $4^{+}$ states at 2.61, 3.20, 4.10, and 4.31 MeV, respectively, show pronounced effects due to interference between Coulomb and nuclear excitation. The data are well reproduced by distorted-wave calculations provided that the phase of the nuclear excitation form factor is altered by 5° from that given by the collective model.