Enhanced mixing of intrinsic states in deformed Hf nuclei

Abstract

Excited low-spin, nonyrast states in (170,172,174)Hf were populated in beta(+)/epsilon decay and studied through off-beam, gamma-ray spectroscopy. New coincidence data allowed for a substantial revision of the level schemes (170,174)Hf and a confirmation of the level scheme of (174)Hf. The Hf isotopes represent a unique situation in which a crossing of collective intrinsic excitations occurs, enhancing significantly the effects of mixing. Using branching ratios from excited 2(+) states, this mixing is followed and studied. The resulting mixing matrix elements are found to be similar to 30 keV-an order of magnitude larger than estimated previously for nearby nuclei. In the case of (170)Hf, the 2(beta)(+) and 2(gamma)(+) level are shown to be completely mixed.