Observation of the lowest energy gamma-ray in any superdeformed nucleus : 196Bi

Abstract

New results on the superdeformed ${}^{196}$Bi nucleus a re reported. We have observed with the EUROBALL IV ${\hat{I}}^3$-ray spectrometer array a superdeformed trans ition of 124 keV which is the lowest observed energy ${\hat{I}}^3$-ray in any superdeformed nucleus. We have de velopped microscopic cranked Hartree-Fock-Bogoliubov calculations using the SLy4 effective force and a realistic surface p airing which strongly support the $K^{\ddot{I}}€=2^{-}$($\ddot{I}€$[651]1/2$\otimes \hat{I}½$[752]5/2) assignment of this su perdeformed band.