How elements up to 118 were reached and how to go beyond
Institute of Nuclear Chemistry, Johannes Gutenberg University, 55128 Mainz, Germany
2 GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
3 Helmholtz Institute Mainz, 55099 Mainz, Germany
4 Australian National University, Canberra, ACT 2601, Australia
* e-mail: firstname.lastname@example.org
Published online: 22 November 2017
The new superheavy elements with Z=113, 115, 117, and 118 were recently accepted into the periodic table and have been named. Elements with Z≥112 are predominantly produced in 48Ca-induced fusion reactions on actinide targets. This pathway is exhausted at Z=118 due to the lack of target materials with sufficiently high proton number to reach elements with Z≥119. Search experiments for yet heavier elements were performed at GSI Darmstadt and FLNR Dubna. The reactions 50Ti + 249Bk, which leads to Z=119, as well as 64Ni + 238U, 58Fe + 244Pu, 54Cr + 248Cm, and 50Ti + 249Cf, leading to Z=120, have been studied. Despite a total duration of these experiments of more than one year, neither succeeded in the identification of a new element. To obtain improved guidance for better-informed search experiments, nuclear reaction studies appear necessary and have recently started. Also technical advances will be an important pillar to this end. At GSI, work towards a new continuous-wave linear accelerator is ongoing and is briefly described.
© The Authors, published by EDP Sciences, 2017
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