BACKBENDING PHENOMENON IN CR-48

A new mechanism for the backbending phenomenon in Cr-48 is discussed b ased on a careful analysis of the yrast band, where no level crossing of the single-particle orbits is expected. A newly developed numerical code for solving the self-consistent cranked Hartree-Fock-Bogoliubov (HFB) equation with a maximum overlap criterion is applied to Cr-48, a nd various continuous cranked HFB solutions forming many rotational ba nds are obtained. By using the first derivative of the cranked HFB wav e function with respect to the total angular momentum, and by comparin g the Thouless-Valatin and the Inglis moments of inertia, it is pointe d out that a fully self-consistent mean-field treatment, which properl y takes into account the two-body residual interaction, is crucial in explaining cases of backbending phenomena that are not associated with a single-particle level crossing. [S0556-2813(98)00211-8].