The Impact of Recent LUNA Measurements of NeNa Reactions on 26 Al Stellar Nucleosynthesis

Journal article

Recent measurements performed by the LUNA(Laboratory for Underground Nuclear Astrophysics) collaboration between 2019 and 2024 have provided the most precise direct determinations to date of several key reaction rates in the NeNa cycle, specifically the 20Ne(p, γ)21Na and the 22Ne(p, γ)23Na reactions, as well as its bridge to the MgAl cycle, i.e., the 23Na(p, γ)24Mg reaction. Despite their improved accuracy, these updated rates are not yet consistently incorporated into widely used nuclear reaction network compilations. We explore the astrophysical impact of adopting the new LUNA rates by performing nucleosynthesis calculations, focusing on the case of 26Al nucleosynthesis and considering four different stellar environments: low-mass AGB stars, massive stars, very massive stars and core-collapse supernovae. Our results show substantial sensitivity of 26Al production to the revised rates. In the AGB model, the surface 26Al abundance decreases by up to 30%, while in the massive star model, the 26Al abundance in the C-burning shell increases by 51%. In contrast, the impact on both the 26Al yields ejected by very massive stars and on the explosive nucleosynthesis in the supernova model is negligible. These findings have direct implications for galactic chemical evolution, the global budget of 26Al, and theoretical predictions of the 60Fe/26Al ratio, which will be critically tested by forthcoming γ-ray observations from missions such as the Compton Spectrometer and Imager (COSI).

Authors: Battino, U; Gallo, T; Vescovi, D; Cristallo, S; Best, A

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: MDPI
• Journal: Universe
• Volume: 12
• Issue: 3
• Pages: 70
• Article number: 70
• Publication date: 2026-03-02
• Acceptance date: 2026-02-25
• DOI: 10.3390/universe12030070
• EISSN: 2218-1997
• ISSN: 2218-1997
• Language: English
• Keywords: stellar interiors; evolved stars; stellar evolution; nucleosynthesis