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arXiv · 2305.05209

Decay of superheavy nuclei based on the random forest algorithm

Boshuai Cai·Cenxi Yuan
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Abstract

How nuclides decay in the superheavy region is key information for investigating new elements beyond oganesson and the island of stability. The Random Forest algorithm is applied to study the competition between different decay modes in the superheavy region, including $\alpha$ decay, $\beta^-$ decay, $\beta^+$ decay, electron capture and spontaneous fission. The observed half-lives and dominant decay mode are well reproduced. The dominant decay mode of 96.9 % nuclei beyond $^{212}$Po is correctly described. $\alpha$ decay is predicted to be the dominant decay mode for isotopes in new elements $Z = 119 - 122$, except for spontaneous fission in some even-even ones because of the odd-even staggering effect. The predicted half-lives show the existence of a long-lived spontaneous fission island at the southwest of $^{298}$Fl caused by the competition of nuclear deformation and Coulomb repulsion. More understanding of spontaneous fission, especially beyond $^{286}$Fl, is crucial to search for new elements and the island of stability.

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Boshuai Cai, Cenxi Yuan. 2023-05-09. Decay of superheavy nuclei based on the random forest algorithm. https://doi.org/10.1007/s41365-023-01354-5

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