Low-spin states in Ge-80 populated in the beta decay of the Ga-80 3(-) isomer

0544862 - ÚJF 2022 RIV US eng J - Journal Article
Sekal, S. - Fraile, L. M. - Lica, R. - Borge, M. J. G. - Walters, W. B. - Aprahamian, A. - Benchouk, C. - Bernards, C. - Briz, J. A. - Bucher, B. - Chiara, C. J. - Dlouhý, Zdeněk - Gheorghe, I. - Ghita, D. G. - Hoff, P. - Jolie, J. - Koster, U. - Kurcewicz, W. - Mach, H. - Marginean, N. - Marginean, R. - Meliani, Z. - Olaizola, B. - Paziy, V. - Regis, J. M. - Rudigier, M. - Sava, T. - Simpson, G. S. - Stanoiu, M. - Stroe, L.
Low-spin states in Ge-80 populated in the beta decay of the Ga-80 3(-) isomer.
Physical Review C. Roč. 104, č. 2 (2021), č. článku 024317. ISSN 2469-9985. E-ISSN 2469-9993
Institutional support: RVO:61389005
Keywords : Ge-80 * Shell-model calculations * shape coexistence
OECD category: Nuclear physics
Impact factor: 3.199, year: 2021
Method of publishing: Open access
https://doi.org/10.1103/PhysRevC.104.024317

The structure of Ge-80 has been investigated at the ISOLDE facility at CERN. A previous study reported for the first time a low-lying 0(2)(+) intruder state at 639 keV, based on the coincidence with a previously unobserved 1764-keV gamma ray, and suggested it as evidence for shape coexistence in Ge-80. We used the beta decay from the 3(-) 22.4-keV state in Ga-80 to enhance the population of low-spin states in Ge-80, including any excited 0(+) level, and gamma gamma coincidences to investigate it. We observed a 1764-keV gamma ray in coincidence with strong transitions in Ge-80, thus not feeding the proposed 639-keV 0(2)(+). No connecting transitions from previously known levels to the 639-keV and 2403-keV 2(3)(+) states could be established either. Shell-model calculations for Ge isotopes and N = 48 isotones were performed. They succeed to explain most of the experimental levels, but fail to reproduce the presence of a 0(2)(+) state below approximate to 1200 keV in Ge-80. Our experimental findings and shell-model calculations are difficult to reconcile with a very low-lying 0(2)(+) state in Ge-80.
Permanent Link: http://hdl.handle.net/11104/0321661