A discrete superdeformed rotational band has been discovered in ${}_{}{}^{144}{}_{}{}^{}\mathrm{Gd}$ following the reaction ${}_{}{}^{100}{}_{}{}^{}\mathrm{Mo}$${(}^{48}$Ti, 4n${)}^{144}$Gd at 221 MeV. The dynamical moment of inertia shows a sharp irregularity at ħω=0.45 MeV. The intensity of the γ-ray transitions suggests that the irregularity can be associated with a backbend, which is interpreted in terms of the N=6 proton band crossing. The experimental results are in good agreement with cranked mean field calculations, which indicate the presence of large shell gaps for both protons and neutrons.

• Received 23 November 1993

DOI:https://doi.org/10.1103/PhysRevLett.72.1427