High-spin states in the odd-neutron Ba131 nucleus have been populated following the Sn122(13C,4n) reaction. Several rotational bands were established using - coincidence techniques. The yrast band, built on a h11/2 orbital, has a relatively large signature splitting (160 keV). Cranking calculations suggest a significant triaxial shape with 0°for this configuration. A pair of h11/2 protons align at a rotational frequency Latin small letter h with stroke0.43 MeV and drive the nucleus towards a near-prolate shape (0°), which is manifest by the observation of a I=1 band with strong dipole transitions and a small signature inversion. At a similar frequency, pairs of h11/2 neutrons align and drive the nucleus to near-oblate (-60°) shapes, resulting in the observation of decoupled I=2 bands.
ASJC Scopus subject areas
- Nuclear and High Energy Physics