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arXiv · 2602.09480

Three-Body Barrier Dynamics of Double-Alpha Decay in Heavy Nuclei

Shulin Tang·Tao Wan·Yibin Qian·Chong Qi·Ramon A. Wyss·Roberto J. Liotta·Dong Bai·Bo Zhou·Zhongzhou Ren
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Abstract

The simultaneous emission of two $α$ particles--double-$α$ decay--represents a long-predicted but unobserved mode of nuclear radioactivity. Here we formulate this process as a genuine three-body problem within the hyperspherical coordinate framework and evaluate decay probabilities by numerically solving the corresponding hyperradial Schrödinger equation, combined with large-scale random sampling of the potential parameters; the latter treatment ensures that the present results are more convincing. Inspired by this, we demonstrate that the penetrability ratio between simultaneous and sequential $α$ emission exhibits a strikingly linear dependence on $ZQ_{αα}^{-1/2}$, extending the barrier penetration dynamics into the correlated few-body regime. The nuclei $^{108}$Xe, $^{218}$Ra, $^{224}$Pu, $^{222}$U, $^{216}$Rn, and $^{220}$Th are suggested as the most promising candidates for the observation of double-$α$ decay, with predicted half-lives potentially accessible within present detection limits. Our results provide a unified framework for multi-$α$ decay and open a pathway to probing nuclear clustering and few-body correlations in heavy nuclei.

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Shulin Tang, Tao Wan, Yibin Qian, Chong Qi, Ramon A. Wyss, Roberto J. Liotta, Dong Bai, Bo Zhou, Zhongzhou Ren. 2026-02-10. Three-Body Barrier Dynamics of Double-Alpha Decay in Heavy Nuclei. https://arxiv.org/abs/2602.09480

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