A1 Journal article (refereed)
Long-sought isomer turns out to be the ground state of 76Cu (2024)

Canete, L., Giraud, S., Kankainen, A., Bastin, B., Nowacki, F., Ascher, P., Eronen, T., Girard Alcindor, V., Jokinen, A., Khanam, A., Moore, I. D., Nesterenko, D., De Oliveira, F., Penttilä, H., Petrone, C., Pohjalainen, I., De Roubin, A., Rubchenya, V., Vilen, M., & Äystö, J. (2024). Long-sought isomer turns out to be the ground state of 76Cu. Physics Letters B, In Press. https://doi.org/10.1016/j.physletb.2024.138663

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Publication details

All authors or editorsCanete, L.; Giraud, S.; Kankainen, A.; Bastin, B.; Nowacki, F.; Ascher, P.; Eronen, T.; Girard Alcindor, V.; Jokinen, A.; Khanam, A.; et al.

Journal or seriesPhysics Letters B



Publication year2024

Publication date22/04/2024

VolumeIn Press


Publication countryNetherlands

Publication languageEnglish


Publication open accessOpenly available

Publication channel open accessOpen Access channel

Web address of parallel published publication (pre-print)https://arxiv.org/abs/2401.14018


Isomers close to the doubly magic nucleus 78Ni (Z = 28, N = 50) provide essential information on the shell evolution and shape coexistence far from stability. The existence of a long-lived isomeric state in 76Cu has been debated for a long time. We have performed high-precision mass measurements of 76Cu with the JYFLTRAP double Penning trap mass spectrometer at the Ion Guide Isotope Separator On-Line facility and confirm the existence of such an isomeric state with an excitation energy Ex = 64.8(25) keV. Based on the ratio of detected ground- and isomeric-state ions as a function of time, we show that the isomer is the shorter-living state previously considered as the ground state of 76Cu. The result can potentially change the conclusions made in previous works related to the spin-parity and charge radius of the 76Cu ground state. Additionally, the new 76Cu(n, γ) reaction Q-value has an impact on the astrophysical rapid neutron-capture process.

Keywordscopperisotopesnuclear physics

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Ministry reportingYes

Reporting Year2024

Preliminary JUFO rating3

Last updated on 2024-15-06 at 00:46