2019 Impact factor 2.176
Hadrons and Nuclei


Eur. Phys. J. A 14, 147-157 (2002)
DOI: 10.1140/epja/i2001-10119-x

New results on elements 111 and 112

S. Hofmann1, F.P. Heßberger1, D. Ackermann1, G. Münzenberg1, S. Antalic2, P. Cagarda2, B. Kindler1, J. Kojouharova1, M. Leino3, B. Lommel1, R. Mann1, A.G. Popeko4, S. Reshitko1, S. Saro2, J. Uusitalo3 and A.V. Yeremin4

1  Gesellschaft für Schwerionenforschung (GSI), D-64220 Darmstadt, Germany
2  Department of Nuclear Physics, Comenius University, SK-84248 Bratislava, Slovakia
3  Department of Physics, University of Jyväskylä, FIN-40351 Jyväskylä, Finland
4  Flerov Laboratory of Nuclear Reactions, JINR, RU-141 980 Dubna, Russia

S.Hofmann@gsi.de

(Received: 21 December 2001 Communicated by D. Schwalm)

Abstract
This paper is dedicated to our former department leader P. Armbruster on the occasion of his 70th birthday - Experiments on the synthesis and identification of the nuclei 272111 and 277112 were performed in order to confirm previous results. Three additional decay chains were measured in the reaction $\chem{^{64}Ni + {}^{209}Bi \rightarrow
{}^{273}111^*}$ . The study revealed considerably improved data on the decay chain originating from 272111. One additional chain was measured in the reaction $\chem{^{70}Zn + {}^{208}Pb \rightarrow{}
^{278}112^*}$ . The decay properties of the chain starting at 277112 are in excellent agreement with the second chain of the first experiment down to 265Sg, where the new chain ends by a previously unknown spontaneous-fission branch. A re-analysis of all the data on elements 110, 111, and 112 measured at GSI since 1994 (a total of 34 decay chains was investigated) revealed that for 2 chains (the second chain of 269110 measured in 1994 and the first chain of 277112 measured in 1996) the results of the new analysis differed from the previous one. In all other cases the earlier data are exactly reproduced.

PACS
23.60.+e - Alpha decay.
25.70.-z - Low and intermediate energy heavy-ion reactions.
25.85.Ca - Spontaneous fission.
27.90.+b - $A\geq 220$ .

© Società Italiana di Fisica, Springer-Verlag 2002