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Author(s): Ivan Mukha (corresponding author) [1, 2, 3, 10]; Ernst Roeckl [1]; Leonid Batist [4]; Andrey Blazhev [1, 5]; Joachim Doring [1]; Hubert Grawe [1]; Leonid Grigorenko [6]; Mark Huyse [...]

Seven years ago, the GSI Online Mass Separator was decommissioned after 30 years of operation. The Golden Age of Jan Żylicz, celebrated at this Conference, is an adequate occasion to review the research performed at this facility. Its programme reached from nuclear-structure studies based on decay spectroscopy -- the focus of this contribution -- to investigations of nuclear shapes by means of laser spectroscopy all the way to experiments of astrophysical and fundamental-physics relevance. Reviewing this work I shall present my personal view on, firstly, examples of technical and scientific highlights and, secondly, the "humanistic" aspect of collaborating with many colleagues from abroad, including in particular Jan Żylicz and his associates from the University of Warsaw. [ABSTRACT FROM AUTHOR]

The properties observed for the one-proton and two-proton radioactivity of the (21+) isomer in 94Ag are briefly summarized. The occurrence of both types of radioactivity from one and the same nuclear state is a unique phenomenon on the entire chart of nuclides. In particular, the first observation of energy correlations for two-proton radioactivity is discussed in comparison with predictions obtained from of a three-body breakup model. On the basis of this comparison it is tentatively suggested that the two protons are emitted simultaneously either from one of the poles or from opposite poles of a strongly deformed nucleus. Future experimental and theoretical studies are sketched which may help to explain this puzzling result. [ABSTRACT FROM AUTHOR]

The stability and spontaneous decay of naturally occurring atomic nuclei have been much studied ever since Becquerel discovered natural radioactivity in 1896. In 1960, proton-rich nuclei with an odd or an even atomic number Z were predicted to decay through one- and two-proton radioactivity, respectively. The experimental observation of one-proton radioactivity was first reported in 1982, and two-proton radioactivity has now also been detected by experimentally studying the decay properties of 45Fe (refs 3, 4) and 54Zn (ref. 5). Here we report proton–proton correlations observed during the radioactive decay of a spinning long-lived state of the lightest known isotope of silver, 94Ag, which is known to undergo one-proton decay. We infer from these correlations that the long-lived state must also decay through simultaneous two-proton emission, making 94Ag the first nucleus to exhibit one- as well as two-proton radioactivity. We attribute the two-proton emission behaviour and the unexpectedly large probability for this decay mechanism to a very large deformation of the parent nucleus into a prolate (cigar-like) shape, which facilitates emission of protons either from the same or from opposite ends of the ‘cigar’. [ABSTRACT FROM AUTHOR]

Following his studies at the universities of Munich and Freiburg, Hubert received his doctorate in Freiburg at the end of the 1960s under the supervision of Theodor Schmidt. Graph Hubert Grawe It is with deep sadness that we have to inform you that Hubert Grawe passed away suddenly on 8 November 2020 at the age of 82. Hubert followed this research line at the Hahn-Meitner-Institut (HMI) in Berlin, where he first worked on combining solid-state physics and nuclear physics to derive precise nuclear moments. [Extracted from the article]