Evidence for spherical-oblate shape coexistence in Tc 87

Abstract

Excited states in the neutron-deficient nucleus Tc87 have been studied via the fusion-evaporation reaction Fe54(Ar36,2n1p)Tc87 at 115 MeV beam energy. The AGATA γ-ray spectrometer coupled to the DIAMANT, NEDA, and Neutron Wall detector arrays for light-particle detection was used to measure the prompt coincidence of γ rays and light particles. Six transitions from the deexcitation of excited states belonging to a new band in Tc87 were identified by comparing γ-ray intensities in the spectra gated under different reaction channel selection conditions. The constructed level structure was compared with the shell model and total Routhian surface calculations. The results indicate that the new band structure in Tc87 is built on a spherical configuration, which is different from that assigned to the previously identified oblate yrast rotational band.

Metadata

Authors/Creators:

Liu, X.
Cederwall, B.
Qi, C.
Wyss, R. A.
Aktas
Ertoprak, A.
Zhang, W.
Clément, E.
De France, G.
Ralet, D.
Gadea, A.
Goasduff, A.
Jaworski, G.
Kuti, I.
Nyakó, B. M.
Nyberg, J.
Palacz, M.
Wadsworth, R. https://orcid.org/0000-0002-4187-3102
Valiente-Dobón, J. J.
Al-Azri, H.
Ataç Nyberg, A.
Bäck, T.
De Angelis, G.
Doncel, M.
Dudouet, J.
Gottardo, A.
Jurado, M.
Ljungvall, J.
Mengoni, D.
Napoli, D. R.
Petrache, C. M.
Sohler, D.
Timár, J.
Barrientos, D.
Bednarczyk, P.
Benzoni, G.
Birkenbach, B.
Boston, A. J.
Boston, H. C.
Burrows, I.
Charles, L.
Ciemala, M.
Crespi, F. C.L.
Cullen, D. M.
Désesquelles, P.
Domingo-Pardo, C.
Eberth, J.
Erduran, N.
Ertürk, S.
Simpson, J.

© 2022 authors. Funding Information: This work was supported by the Swedish Research Council under Grants No. 621-2014-5558 and No. 2019-04880; the EU 7th Framework Programme, Integrating Activities Transnational Access, Project No. 262010 ENSAR; the UK STFC under Grants No. ST/L005727/1 and No. ST/P003885/1; the Polish National Science Centre, Grants No. 2016/22/M/ST2/00269 and No. 2017/25/B/ST2/01569; COPIN-INFN, COPIN-IN2P3, and COPIGAL projects; the National Research, Development and Innovation Fund of Hungary (Project No. K128947); the European Regional Development Fund (Contract No. GINOP-2.3.3-15-2016-00034); the Hungarian National Research, Development and Innovation Office, NKFIH, Contract No. PD124717; the Ministerio de Ciencia e Innovación and Generalitat Valenciana, Spain, under the Grants No. SEV-2014-0398 and No. FPA2017-84756-C4; PROMETEO/2019/005; and by the EU FEDER funds. X.L. gratefully acknowledges support from the China Scholarship Council, Grant No. 201700260183, for his stay in Sweden. We acknowledge the support from the AGATA Collaboration and thank the GANIL staff for excellent technical support and operation.

Dates: