Giant resonances inSn112andSn124: Isotopic dependence of monopole resonance energies

Abstract

The giant resonance region from $10\phantom{\rule{0.3em}{0ex}}\mathrm{MeV}<{E}_{x}<55\phantom{\rule{0.3em}{0ex}}\mathrm{MeV}$ in $^{112}\mathrm{Sn}$ and $^{124}\mathrm{Sn}$ has been studied with inelastic scattering of $240\phantom{\rule{0.3em}{0ex}}\mathrm{MeV}$ $\ensuremath{\alpha}$ particles at small angles including 0\ifmmode^\circ\else\textdegree\fi{}. Essentially, all of the expected isoscalar $E0--E3$ strength was located in both nuclei. The isotopic dependence of the giant monopole resonance energies was found to be consistent with relativistic and nonrelativistic calculations for interactions with ${K}_{\mathrm{NM}}\ensuremath{\sim}220--240\phantom{\rule{0.3em}{0ex}}\mathrm{MeV}$.