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arXiv · 1401.7959

Structure of Superheavy Nuclei Along Element 115 Decay Chains

Yue Shi·D. E. Ward·B. G. Carlsson·J. Dobaczewski·W. Nazarewicz·I. Ragnarsson·D. Rudolph
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Abstract

A recent high-resolution $α$, $X$-ray, and $γ$-ray coincidence-spectroscopy experiment offered first glimpse of excitation schemes of isotopes along $α$-decay chains of $Z=115$. To understand these observations and to make predictions about shell structure of superheavy nuclei below $^{288}115$, we employ two complementary mean-field models: self-consistent Skyrme Energy Density Functional approach and the macroscopic-microscopic Nilsson model. We discuss the spectroscopic information carried by the new data. In particular, candidates for the experimentally observed $E1$ transitions in $^{276}$Mt are proposed. We find that the presence and nature of low-energy $E1$ transitions in well-deformed nuclei around $Z=110, N=168$ strongly depends on the strength of the spin-orbit coupling; hence, it provides an excellent constraint on theoretical models of superheavy nuclei. To clarify competing theoretical scenarios, an experimental search for $E1$ transitions in odd-$A$ systems $^{275,277}$Mt, $^{275}$Hs, and $^{277}$Ds is strongly recommended.

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Yue Shi, D. E. Ward, B. G. Carlsson, J. Dobaczewski, W. Nazarewicz, I. Ragnarsson, D. Rudolph. 2014-06-26. Structure of Superheavy Nuclei Along Element 115 Decay Chains. https://doi.org/10.1103/physrevc.90.014308

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