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arXiv · 2606.03316

Possible explanation of primordial $^7$Li deficit

E. V. Arbuzova·A. D. Dolgov
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Abstract

A reduction mechanism of the theoretically predicted excessive abundance of $^7$Li via baryons evaporated by primordial black holes is suggested. It is shown that the fraction of $^7$Li with respect to the number density of baryons can be diminished down to the observed value via the process of $^7$Li transformation by neutron capture. The created in this process $^8$Li or $^8$Be quickly decay into a pair of $^4$He nuclei.

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E. V. Arbuzova, A. D. Dolgov. 2026-06-02. Possible explanation of primordial $^7$Li deficit. https://doi.org/10.1140/epjc%2Fs10052-025-15089-7

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