https://doi.org/10.1140/epja/i2016-16180-4
Review
Review of even element super-heavy nuclei and search for element 120
1
GSI Helmholtzzentrum für Schwerionenforschung, 64291, Darmstadt, Germany
2
Institut für Physik, Goethe-Universität Frankfurt, 60438, Frankfurt, Germany
3
Manipal Centre for Natural Sciences, Manipal University, 576104, Manipal, Karnataka, India
4
Department of Nuclear Physics and Biophysics, Comenius University, 84248, Bratislava, Slovakia
5
Johannes Gutenberg-Universität Mainz, 55128, Mainz, Germany
6
Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
7
University of Tennessee, 37996, Knoxville, TN, USA
8
Department of Physics and Astronomy, Vanderbuilt University, 37235, Nashville, TN, USA
9
Lawrence Livermore National Laboratory, 94551, Livermore, CA, USA
10
University of Warsaw, Warsaw, Poland
11
RIKEN Nishina Center for Accelerator-Based Science, 2-1, Hirosawa, 351-0198, Wako, Saitama, Japan
12
Japan Atomic Energy Agency, 319-1195, Tokai, Ibaraki, Japan
13
Joint Institute for Nuclear Research, 141980, Dubna, Russian Federation
14
Department of Physics, University of Jyväskylä, 40351, Jyväskylä, Finland
* e-mail: S.Hofmann@gsi.de
Received:
2
March
2016
Revised:
18
April
2016
Accepted:
22
April
2016
Published online:
28
June
2016
The reaction
54Cr$ + $248Cm
was investigated at the velocity filter SHIP at GSI, Darmstadt, with the intention to study production and decay properties of isotopes of element 120. Three correlated signals were measured, which occurred within a period of 279ms. The heights of the signals correspond with the expectations for a decay sequence starting with an isotope of element 120. However, a complete decay chain cannot be established, since a signal from the implantation of the evaporation residue cannot be identified unambiguously. Measured properties of the event chain are discussed in detail. The result is compared with theoretical predictions. Previously measured decay properties of even element super-heavy nuclei were compiled in order to find arguments for an assignment from the systematics of experimental data. In the course of this review, a few tentatively assigned data could be corrected. New interpretations are given for results which could not be assigned definitely in previous studies. The discussion revealed that the cross-section for production of element 120 could be high enough so that a successful experiment seems possible with presently available techniques. However, a continuation of the experiment at SHIP for a necessary confirmation of the results obtained in a relatively short irradiation of five weeks is not possible at GSI presently. Therefore, we decided to publish the results of the measurement and of the review as they exist now. In the summary and outlook section we also present concepts for the continuation of research in the field of super-heavy nuclei.
© SIF, Springer-Verlag Berlin Heidelberg, 2016
