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Candidates for Long Lived High-K Ground States in Superheavy Nuclei

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 نشر من قبل Michal Kowal
 تاريخ النشر 2015
  مجال البحث
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On the basis of systematic calculations for 1364 heavy and superheavy nuclei, including odd-systems, we have found a few candidates for high-K ground states in superheavy nuclei. The macroscopic-microscopic model based on the deformed Woods-Saxon single particle potential which we use offers a reasonable description of SH systems, including known: nuclear masses, $Q_{alpha}$-values, fission barriers, ground state deformations, super- and hyper-deformed minima in the heaviest nuclei. %For odd and odd-odd systems, both ways of including pairing correlations, % blocking and the quasi-particle method, have been applied. Exceptionally untypical high-K intruder contents of the g.s. found for some nuclei accompanied by a sizable excitation of the parent configuration in daughter suggest a dramatic hindrance of the $alpha$-decay. Multidimensional hyper-cube configuration - constrained calculations of the Potential Energy Surfaces (PESs) for one especially promising candidate, $^{272}$ Mt, shows a $backsimeq$ 6 MeV increase in the fission barrier above the configuration- unconstrained barrier. There is a possibility, that one such high-K ground- or low-lying state may be the longest lived superheavy isotope.



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