Artificial radioactive element properties unknown	memory peg
	1994 Sigurd Hofmann and co-workers, Darmstadt, Germany
	un-un-bi-um = 1-1-2-ium

First prepared in 1996 by Sigurd Hofmann, Victor Ninov, Fritz Peter Heßberger, Peter Armbruster, H. Folger, Gottfried Münzenberg, H.J. Schött (Gesellschaft für Schwerionenforschung, Darmstadt, Germany), Andre Georgievich Popeko, Alexander Vladimirovich Yeremin, A.N. Andreyev (Лаборатория ядерных реакций им. Г.Н. Флерова / Flerov Laboratory of Nuclear Reactions, FLNR - ОИЯИ / JINR, Дубна (Dubna), Russia), S. Saro, Rudolf Janik (Katedra jadrovej fyziky, Univerzita Komenského, Bratislava, Slovakia), and Matti Leino (Fysiikan laitos, Jyväskylän Yliopisto, Finland).

The element does not have a name yet, therefore the systematic IUPAC name is used (system explained at Ununoctium).

Abstract:

The new element 112 was produced and identified unambiguously in an experiment at SHIP, GSI Darmstadt. Two decay chains of the isotope ²⁷⁷112 were observed in irradiations of ²⁰⁸Pb targets with ⁷⁰Zn projectiles of 343.8 MeV kinetic energy. The istope decays by emission of alpha particles with a half-life of (240 +430 -90) micro seconds. Two different alpha-energies of (11,649+-20)keV and (11,454+-20) keV) were measured for the decaying nuclei. The cross section measured in three weeks of irradiation is (1.0 +1.3 -0.6) pb.

IUPAP/IUPAC Joint working party assessment: The results of this study are of characteristically high quality but there is insufficient internal redundancy to warrant conviction at this stage. Confirmation by further results is needed to assign priority of discovery to this collaboration (Karol et al., 2001, 964).

Further reading:

• S. Hofman et al., "The New Element 112." Zeitschrift für Physik A 354 (1996), 229-230. (Abstract on-line).
• P.J. Karol, H. Nakahara, B.W. Petley, & E. Vogt, On the Discovery of the Elements 110–112 (IUPAC Technical Report). Pure Appl.Chem. 73, 6 (2001), pp.959–967 (PDF file on-line).