Triaxial strongly deformed structures in the even-even Hf nuclei

Department of Physics & Astronomy, Mississippi State University, Mississippi State, MS 39762, U. S. A.

^a e-mail: mawc@ra.msstate.edu

Published online: 3 April 2014

Abstract

Two rotational bands of distinct character have been identified in ¹⁶⁴Hf from a recent experiment at Gammasphere. They are suggested to correspond to the long-anticipated triaxial strongly deformed (TSD) bands predicted by theoretical studies. The bands are substantially stronger in intensity and are located at lower spins than the previously observed TSD bands in ¹⁶⁸Hf, and have been linked to the known states, hereby making ¹⁶⁴Hf the best even-even system for the study of TSD structures in the A ~ 160 mass region. Cranking calculations based on the modified-oscillator model suggest that the bands are associated with four-quasiparticle configurations involving high-j intruder(i_13/2)² proton orbitals. Wobbling mode has not been observed in ¹⁶⁴Hf and the possible reasons are discussed.