Inelastic Scattering ofO16fromPb208

Abstract

The inelastic scattering of $^{16}\mathrm{O}$ from $^{208}\mathrm{Pb}$ has been studied at an incident $^{16}\mathrm{O}$ energy of 104 MeV. The angular distributions to the ${3}^{\ensuremath{-}}$, ${5}^{\ensuremath{-}}$, and ${2}^{+}$ levels at 2.62, 3.20, and 4.10 MeV in $^{208}\mathrm{Pb}$ show interference patterns like those expected from the destructive interference of Coulomb and nuclear excitation. The phase, $\ensuremath{\alpha}$, of the nuclear excitation form factor, is determined to be $\ensuremath{\alpha}=30\ifmmode\pm\else\textpm\fi{}15\ifmmode^\circ\else\textdegree\fi{}$, in good agreement with the collective model. Transition probabilities deduced from the potential deformations are smaller by a factor of \ensuremath{\sim}2 than the electromagnetic transition probabilities measured in ($e,{e}^{\ensuremath{'}}$) or Coulomb excitation.