Observation of the 0(2)(+) and gamma bands in Ru-98, and shape coexistence in the Ru isotopes

Garrett, P. E.; Makhathini, L.; Bark, R. A.; Rodriguez, T. R.; Valbuena, S.; Bildstein, V.; Bucher, T. D.; Burbadge, C.; Dubey, R.; Faestermann, T.; Hertenberger, R.; Kamil, M.; Lawrie, E. A.; Leach, K. G.; MacLean, A. D.; Mehl, C.; Mthembu, S. H.; Mukwevho, N. J.; Ngwetsheni, C.; Ntshangase, S. S.; Ondze, J. C. Nzobadila; Orce, J. N.; Rebeiro, B.; Singh, B.; Triambak, S.; Vyfers, E. C. and Wirth, H.-F. (2020): Observation of the 0(2)(+) and gamma bands in Ru-98, and shape coexistence in the Ru isotopes. In: Physics Letters B, Vol. 809, 135762

Abstract

Excited states in Ru-98 were investigated using gamma-ray spectroscopy following the beta-decay of Rh-98, and via the 100 Ru(p, t) reaction. Combining the results from the two experiments, two states were revised to have spin-parity of 4(+) and subsequently assigned to the 0(2)(+) and "gamma" bands, respectively. The observed structures in Ru-98 are suggested to be deformed and rotational, rather than spherical and vibrational, and fit well into the systematics of these excitations in the Ru isotopes. The 0(2)(+) excitation is suggested as a shape coexisting configuration. This observation eliminates some of the last remaining candidates for nearly harmonic vibrational nuclei in the Z approximate to 50 region. Beyond-mean-field calculations are presented that support shape coexistence throughout the Ru isotopes with N = 52-62, and suggest a smooth evolution of the shapes. (C) 2020 The Authors. Published by Elsevier B.V.

• Item Type: Journal article
• Faculties: Physics
• Subjects: 500 Science > 530 Physics
• ISSN: 0370-2693
• Language: English