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arXiv · 2501.14897

The 3-$\alpha$ and 4-$\alpha$ particle systems within short-range Effective Field Theory

E. Filandri·M. Viviani·L. Girlanda·A. Kievsky·L. E. Marcucci
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Abstract

${}^{12}{\rm C}$ and ${}^{16}{\rm O}$ nuclei represent essential elements for life on Earth. The study of their formation plays a key role in understanding heavy element nucleosynthesis and stellar evolution. In this paper we present the study of ${}^{12}{\rm C}$ and ${}^{16}{\rm O}$ nuclei as systems composed of $\alpha$-particle clusters using the short-range effective field theory approach. The fundamental and excited states of the studied nuclei are calculated within an ab-initio approach, using the Hyperspherical Harmonics method. Thanks to the two-body potential and fine-tuning of the three-body force, we have found the ${}^{12}{\rm C}$ system nicely reproduced by theory. However, for the ${}^{16}{\rm O}$ case, it is necessary to include a 4-body force in order to achieve agreement with the experimental data.

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E. Filandri, M. Viviani, L. Girlanda, A. Kievsky, L. E. Marcucci. 2025-01-24. The 3-$\alpha$ and 4-$\alpha$ particle systems within short-range Effective Field Theory. https://arxiv.org/abs/2501.14897

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