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Recently, long-lived high spin super- and hyperdeformed isomeric states with unusual radioactive decay properties have been discovered. Based on these newly observed modes of radioactive decay, consistent interpretations are suggested for previously unexplained phenomena seen in nature. These are the Po halos, the low-energy enhanced 4.5 MeV α-particle group proposed to be due to an isotope of a superheavy element with Z=108, and the giant halos.

Evidence for the possible existence of a superheavy nucleus with atomic mass number A = 292 and abundance of about 1×10^-12 relative to ²³²Th has been found in a study of natural Th using inductively coupled plasma-sector field mass spectrometry. The measured mass is different from any species with molecular mass of 292, but it matches the predictions for the mass of an isotope with atomic number Z = 122 or a nearby element. Its deduced half-life of t_1/2 ≥ 10⁸ y suggests that a long-lived isomeric state exists in this isotope. The possibility that it might belong to a new class of long-lived high spin super- and hyperdeformed isomeric states is discussed.

Based on the observation of the long-lived isotopes of roentgenium, ²⁶¹Rg and ²⁶⁵Rg(Z = 111, t_1/2≥10⁸y) in natural Au, an experiment was performed to enrich Rg in 99.999% Au. 16 mg of Au were heated in vacuum for two weeks at a temperature of 1127°C(63°C above the melting point of Au). The content of ¹⁹⁷Au and ²⁶¹Rg in the residue was studied with high resolution inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). The residue of Au was 3×10^-6 of its original quantity. The recovery of Rg was a few percent. The abundance of Rg compared to Au in the enriched solution was about 2×10^-6, which is a three to four orders of magnitude enrichment. It is concluded that the evaporation rate of Rg from an Au matrix in vacuum at 63°C above the Au melting point is lower than that of Au. This experiment reinforces our first observation of Rg in a terrestrial material. As before it is concluded that a long-lived isomeric state exists in ²⁶¹Rg and that it probably belongs to a new class of isomeric states, namely high spin (K-type) super- or hyperdeformed isomeric states.