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arXiv · 1402.2182

$\alpha$-decay calculations of heavy nuclei using an effective Skyrme interaction

D. E. Ward·B. G. Carlsson·S. Åberg
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Abstract

Background: For nuclei heavier than $^{208}$Pb $\alpha$ decay is a dominating decay mode, and in the search of new superheavy elements one often observes chains of $\alpha$ decays. Purpose: Explore and test microscopic descriptions of $\alpha$ decay based on theories with effective nuclear interactions. Methods: The nuclear ground states are calculated with the Hartree-Fock-Bogoliubov (HFB) method using the Skyrme interaction. Microscopic $\alpha$-decay formation amplitudes are calculated from the HFB wave functions, and the $R$-matrix formalism is utilized to obtain decay probabilities. Results: Using a large harmonic-oscillator basis we obtain converged $\alpha$-decay widths. A comparison with experiment including all spherical even-even $\alpha$ emitting nuclei shows that the model consistently predicts too small formation amplitudes while relative values are in good agreement with experiment. Conclusions: The method was found to be numerically practical even with a large basis size. The comparison of formation amplitudes suggests that the pairing type correlations included in the HFB approach cannot produce sufficient $\alpha$-particle clustering.

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D. E. Ward, B. G. Carlsson, S. Åberg. 2014-02-10. $\alpha$-decay calculations of heavy nuclei using an effective Skyrme interaction. https://arxiv.org/abs/1402.2182

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