Marchini, N.Nannini, A.Rocchini, M.Rodríguez Frutos, Tomás RaúlOttanelli, M.Gelli, N.Perego, A.Benzoni, G.Blasi, N.Bocchi, G.2024-04-182024-04-182023-09-100370-269310.1016/j.physletb.2023.138067https://hdl.handle.net/20.500.14352/1032252023 Descuento SCOAP Artículo firmado por 24 autoresThe structure of 74Se at low energy was investigated via spectroscopy of internal conversion electrons at the INFN Legnaro National Laboratories (LNL). A set of internal K-conversion coefficients and monopole transition strengths was measured. A large & rho;2(E0; 2+2-+ 2+1 ) & BULL; 103 = 210(130) value was deduced. This result, in addition to a low upper limit for the 0+3-+ 0+2 electron transition, casts in doubt a simple interpretation of the 74Se low-lying structure, in particular the recently proposed spherical, vibrational character. New microscopic beyond-mean-field calculations generally agree with the experimental results and are capable of producing a large & rho;2(E0; 2+2-+ 2+1 ) value, even if still a factor & AP;7 smaller than the experiment. Triaxiality and a complex shape-coexistence and mixing scenario seem responsible for this unexpected experimental result.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article1873-2445https//doi.org/10.1016/j.physletb.2023.138067https://www.sciencedirect.com/science/article/pii/S037026932300401Xopen access539.1Electric monopole (E0) transitionsInternal conversionNuclear structureFísica nuclear2207 Física Atómica y Nuclear