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arXiv · 2601.11180

Fine-tunings in radiative $\alpha$-particle capture on $^{12}$C at astrophysical energies

Ulf-G. Meißner·Bernard Ch. Metsch·Helen Meyer
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Abstract

We investigate the fine-tuning of radiative alpha-particle capture on carbon, $\alpha(^{12}{\rm C},^{16}{\rm O})\gamma$, at astrophysical energies. Utilizing results from cluster effective field theory for this reaction, we find that the low-energy data of the astrophysical S-factor allow for only very small variations in the electromagnetic fine-structure constant $\alpha$, namely $|\delta \alpha/\alpha| \leq 0.2\,$ per mille, in both the $E1$ and the $E2$ radiative capture.

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Ulf-G. Meißner, Bernard Ch. Metsch, Helen Meyer. 2026-01-16. Fine-tunings in radiative $\alpha$-particle capture on $^{12}$C at astrophysical energies. https://arxiv.org/abs/2601.11180

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