A1 Journal article (refereed)
Lifetime measurements of excited states in 169,171,173Os : Persistence of anomalous B(E2) ratios in transitional rare earth nuclei in the presence of a decoupled i13/2 valence neutron (2021)


Zhang, W., Cederwall, B., Doncel, M., Aktas, Ö., Ertoprak, A., Liotta, R., Qi, C., Grahn, T., Nara, S. B., Cullen, D.M., Hodge, D., Giles, M., Stolze, S., Badran, H., Braunroth, T., Calverley, T., Cox, D.M., Fang, Y.D., Greenlees, P.T., . . . Valiente-Dobón, J.J. (2021). Lifetime measurements of excited states in 169,171,173Os : Persistence of anomalous B(E2) ratios in transitional rare earth nuclei in the presence of a decoupled i13/2 valence neutron. Physics Letters B, 820, Article 136527. https://doi.org/10.1016/j.physletb.2021.136527


JYU authors or editors


Publication details

All authors or editors: Zhang, W.; Cederwall, B.; Doncel, M.; Aktas, Ö.; Ertoprak, A.; Liotta, R.; Qi, C.; Grahn, T.; Nara, Singh B.S.; Cullen, D.M.; et al.

Journal or series: Physics Letters B

ISSN: 0370-2693

eISSN: 1873-2445

Publication year: 2021

Volume: 820

Article number: 136527

Publisher: Elsevier BV

Publication country: Netherlands

Publication language: English

DOI: https://doi.org/10.1016/j.physletb.2021.136527

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/77284


Abstract

Lifetimes of low-lying excited states in the νi13/2+ bands of the neutron-deficient osmium isotopes 169,171,173Os have been measured for the first time using the recoil-distance Doppler shift and recoil-isomer tagging techniques. An unusually low value is observed for the ratio B(E2; 21/2+ →17/2+)/B(E2; 17/2+ → 13/2+) in 169Os, similar to the “anomalously” low values of the ratio B(E2; 41+ → 21+)/B(E2; 21+ → 0+gs) previously observed in several transitional rare-earth nuclides with even numbers of neutrons and protons, including the neighbouring 168,170Os. Furthermore, the evolution of B(E2; 21/2+ → 17/2+)/B(E2; 17/2+ → 13/2+) with increasing neutron number in the odd-mass
isotopic chain 169,171,173Os is observed to follow the same trend as observed previously in the even-even Os isotopes. These findings indicate that the possible quantum phase transition from a seniority conserving structure to a collective regime as a function of neutron number suggested for the even-even systems is maintained in these odd-mass osmium nuclei, with the odd valence neutron merely acting as a “spectator”. As for the even-even nuclei, the phenomenon is highly unexpected for nuclei that are not situated near closed shells.


Keywords: nuclear physics; isotopes; neutrons; protons


Contributing organizations


Ministry reporting: Yes

Reporting Year: 2021

JUFO rating: 2


Last updated on 2024-03-04 at 19:55