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Response to the IUPAC/IUPAP Joint Working Party Second Report 'On the Discovery of Elements 110-118'

A. Marinov·S. Gelberg·D. Kolb·G. W. A. Newton
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Abstract

Back in 1971 fission fragments were observed by us in Hg sources separated from two CERN W targets that were irradiated with 24 GeV protons. The masses of the fissioning species were measured and heavy masses like 272, 308 and 317-318 were found and interpreted as due to the superheavy element 112 with 160-161 neutrons and various molecules of it. Based on the measured mass of the produced superheavy nucleus cold fusion reactions like 88Sr + 184W -> 272(112) and 86Sr + 186W -> 272(112) were deduced. The ordinary heavy ion reaction 88Sr + 184W has been studied and characteristic X-rays of element 112 and a very high-energy alpha particle in coincidence with a fission fragment have been observed. The data have been studied by the TWG and they were concerned about the question of the reaction mechanism since very large fusion cross sections, in the region of a few mb, have been deduced in the secondary reaction experiments. This question can now be answered in view of our recent discovery of long-lived super- and hyperdeformed isomeric states. The JWP did not accept our arguments and this response answers their queries.

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A. Marinov, S. Gelberg, D. Kolb, G. W. A. Newton. 2004-11-09. Response to the IUPAC/IUPAP Joint Working Party Second Report 'On the Discovery of Elements 110-118'. https://arxiv.org/abs/nucl-ex/0411017

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