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arXiv · 2002.08482

Assessment of the beta-delayed proton decay rate of $^{11}$Be

Alexander Volya
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Abstract

The $^{11}$Be neutron halo nucleus appears to decay into $^{10}$Be with a rate that exceeds expectations. Neutron disappearance into dark matter, beta decay of a halo neutron, or beta-delayed proton decay have been offered as explanations. In this work we study the latter option; we carry out shell model calculations and sequential decay analysis examining the beta-delayed proton decay going through a resonance in $^{11}$B. The narrow energy window, lack of states with sufficient spectroscopic strength, overwhelming alpha decay branch, all make reconciling the observed rate with beta-delayed proton decay difficult.

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Alexander Volya. 2020-02-19. Assessment of the beta-delayed proton decay rate of $^{11}$Be. https://doi.org/10.1209/0295-5075/130/12001

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