Study of Collective Levels in Tin-116, Tin-120, and Tin-124 by Inelastic Electron Scattering

We have observed the inelastic scattering of 150-MeV electrons from tin-116, tin-120, and tin-124. The main ${2}^{+}$ and ${3}^{\ensuremath{-}}$ states have been studied. By comparison of the reduced transition probabilities ${B}_{\mathrm{exp}}(L\ensuremath{\rightarrow}0)$ with the corresponding single-particle estimates ${B}_{I}(L\ensuremath{\rightarrow}0)$, we have measured the collective character of these levels which changes appreciably from one isotope to another.