Identification of sub-μs isomeric states in the odd-odd nucleus 178Au

Abstract

The neutron-deficient gold (Z=79) isotopes in the vicinity of the neutron midshell N=104 provide prolific examples of shape coexistence and isomerism at low excitation energy. They can be probed via a number of different experimental techniques. In this study, two new isomeric states with half-lives of 294(7) and 373(9) ns have been observed in the neutron-deficient odd-odd nuclide Au178 (N=99) in an experiment at the RITU gas-filled separator at JYFL, Jyväskylä. This result was achieved due to the use of a segmented planar germanium detector with a high efficiency at low energies. By applying the recoil-decay tagging technique, they were assigned to decay to two different long-lived α-decaying states in Au178.

Metadata

Authors/Creators:

Gillespie, S. A. (sg581@york.ac.uk)
Stott, A.
Andreyev, A. N. https://orcid.org/0000-0003-2828-0262
Cubiss, J. G. https://orcid.org/0000-0002-5076-8654
Al Monthery, M.
Barton, C. J. https://orcid.org/0000-0001-5125-9619
Antalic, S.
Auranen, K.
Badran, H.
Cox, D.
Grahn, T.
Greenlees, P. T.
Herzan, A.
Higgins, E. (ejh516@york.ac.uk)
Julin, R.
Juutinen, S.
Klimo, J.
Konki, J.
Leino, M.
Mallaburn, M.
Pakarinen, J.
Papadakis, P.
Partanen, J.
Prajapati, P. M.
Rahkila, P.
Sandzelius, M.
Scholey, C.
Sorri, J.
Stolze, S.
Urban, R.
Uusitalo, J.
Venhart, M.
Wearing, F.

Funding Information: The authors wish to thank the technical staff at the Accelerator Laboratory at the University of Jyväskylä for their excellent support. This work was supported by the United Kingdom Science and Technology Facility Council Grant No. ST/P003885/1, the EU 7th Framework Programme “Integrating Activities - Transnational Access,” Project No. 262010 (ENSAR), the Academy of Finland under the Finnish Centre of Excellence Programme 2012–2017 (Nuclear and Accelerator Based Physics Programme at JYFL), the Slovak Research and Development Agency under Contracts No. APVV-15-0225 and No. APVV-14-0524, and the Slovak Grant Agency VEGA (Contracts No. 2/0129/17 and No. 1/0532/17). The authors also acknowledge the support of GAMMAPOOL for the loan of the JUROGAM detectors. A part of results in this study constitutes the Ph.D. thesis by A.S. ©2021 American Physical Society. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details

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