Isospin character of the ‘‘isoscalar’’ giant quadrupole resonance inSn118

The scattering of 84-MeV/nucleon ${}_{}{}^{17}{}_{}{}^{}\mathrm{O}$ ions by ${}_{}{}^{118}{}_{}{}^{}\mathrm{Sn}$ has been studied. Inelastic cross sections for excitation of the 2.327-MeV state ($3^{\mathrm{-}}$), the giant quadrupole resonance, and the giant monopole resonance are reproduced by distorted-wave approximation calculations using the deformed potential model and assuming isoscalar transitions. A minimum predicted in the angular distribution at ${\mathrm{\theta }}_{\mathrm{c}.\mathrm{m}.\mathrm{}}$=1.9° from utilization of the small B(E2)↑ strength suggested by ${\mathrm{\pi }}^{+}$/${\mathrm{\pi }}^{\mathrm{-}}$ scattering is not apparent in the data.