Two low lying positive-parity bands in 130Cs have been examined for chiral signatures. Small energy differences between the two bands, which have been previously observed, have been confirmed and the bands, as well as the number of transitions within and between the bands, extended. The intraband B(M1)/B(E2) ratios and B(M1)intraband/B(M1)interband ratios and the energy staggering parameter, S(I), have been deduced for these partner bands. The results are found to be consistent with a chiral interpretation for the two structures. Core–quasiparticle coupling model calculations have been performed to study 130Cs assuming a triaxial core. The experimental level energies and electromagnetic properties of the bands, resulting from the configuration, are reasonably well reproduced by the model, providing further evidence in support of the chiral interpretation of the two structures.

A new frontier of discrete-line gamma-ray spectroscopy at ultrahigh spin has been opened in the rare-earth nuclei (157,158) Er. Four rotational structures, displaying high moments of inertia, have been identified, which extend up to spin approximately 65 variant Planck's over 2pi and bypass the band-terminating states in these nuclei which occur at approximately 45 variant Planck's over 2pi. Cranked Nilsson-Strutinsky calculations suggest that these structures arise from well-deformed triaxial configurations that lie in a valley of favored shell energy which also includes the triaxial strongly deformed bands in (161-167) Lu.

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