The inelastic scattering of 64.8 MeV protons has been studied on the stable even ${}_{}{}^{74\mathrm{-}82}{}_{}{}^{}\mathrm{Se}$ isotopes. The inelastically scattered protons were momentum analyzed in a magnetic spectrograph with a resulting energy resolution of approximately 20 keV. Levels up to the excitation energy of about 5 MeV were investigated. Many new levels were observed for the isotopes studied. The angular distributions obtained were compared with the predictions of distorted-wave Born approximation and coupled-channels calculations and a number of new spin assignments were proposed. Several $4^{+}$ states with comparable strengths were found at about $E_x$=2.0–5.0 MeV, showing large fragmentation of octupole and hexadecapole transition strengths, in contrast to the case of Zn isotopes. The distributions of the transition strengths for the $2^{+}$, $3^{\mathrm{-}}$, and $4^{+}$ states were compared with the theoretical calculations based on the random-phase-approximation model for spherical nuclei.

• Received 12 September 1985

DOI:https://doi.org/10.1103/PhysRevC.33.71