Fluorine Nucleosynthesis in AGB Stars in the Light of the 19F(p,α)16O and the 19F(α,p)22Ne Reaction Rate Measured via the Trojan Horse Method

AbstractThe 18O(p, α)15N reaction rate has been extracted by means of the Trojan-Horse method. For the first time the contribution of the 20-keV peak has been directly evaluated, giving a value about 35% larger than previously estimated. The present approach has allowed to improve the accuracy of a factor 8.5, as it is based on the measured strength instead of educated guesses or spectroscopic measurements. The contribution of the 90-keV resonance has been determined as well, which turned out to be of negligible importance to astrophysics.

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The 19F(α, p)22Ne Reaction at Energies of Astrophysical Relevance by Means of the Trojan Horse Method and Its Implications in AGB Stars

The Astrophysical Journal ◽

10.3847/1538-4357/aac207 ◽

2018 ◽

Vol 860 (1) ◽

pp. 61 ◽

Cited By ~ 16

Author(s):

G. D’Agata ◽

R. G. Pizzone ◽

M. La Cognata ◽

I. Indelicato ◽

C. Spitaleri ◽

...

Keyword(s):

Trojan Horse ◽

Agb Stars ◽

Trojan Horse Method

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The 19F(α, p)22Ne and 23Na(p,α)20Ne reaction in AGB nucleosynthesis via THM

EPJ Web of Conferences ◽

10.1051/epjconf/2018184h02003 ◽

2018 ◽

Vol 184 ◽

pp. 02003 ◽

Cited By ~ 1

Author(s):

G. D’Agata ◽

R. G. Pizzone ◽

M. La Cognata ◽

I. Indelicato ◽

C. Spitaleri ◽

...

Keyword(s):

Stable Isotope ◽

Energy Range ◽

Globular Clusters ◽

Trojan Horse ◽

The Other ◽

Agb Stars ◽

Mixing Processes ◽

Trojan Horse Method ◽

Three Body ◽

The Universe

In AGB environment, fluorine and sodium abundances are still matter of debate. About 19F (only stable isotope of fluorine), its abundance in the universe is strictly related to standard and extra-mixing processes taking place inside AGB-stars, that are considered to be the most important sites for its production. Nevertheless the way in which it is destroyed is far from being well understood. On the other hand, 23Na presence in Globular Clusters, along with is well-known anticorrelation with oxygen has made clear that this element must be produced in previous generations stars, and intermediatemass AGB stars are one of the possible candidates for its production. For this reason we studied the 19F(α,p)22Ne and 23Na(p,α)20Ne reactions in the energy range of relevance for astrophysics via the Trojan Horse Method (THM), using the three-body reactions 6Li(19F, p22Ne)d and 23Na(d, pn)20Ne.

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Recent evaluation of the7Li(p,α)4He reaction rate at astrophysical energies via the Trojan Horse method

Astronomy and Astrophysics ◽

10.1051/0004-6361/201219014 ◽

2012 ◽

Vol 541 ◽

pp. A158 ◽

Cited By ~ 49

Author(s):

L. Lamia ◽

C. Spitaleri ◽

M. La Cognata ◽

S. Palmerini ◽

R. G. Pizzone

Keyword(s):

Reaction Rate ◽

Trojan Horse ◽

Trojan Horse Method ◽

Recent Evaluation

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Experimental Nuclear Astrophysics With the Light Elements Li, Be and B: A Review

Frontiers in Astronomy and Space Sciences ◽

10.3389/fspas.2020.589240 ◽

2021 ◽

Vol 7 ◽

Author(s):

G.G. Rapisarda ◽

L. Lamia ◽

A. Caciolli ◽

Chengbo Li ◽

S. Degl’Innocenti ◽

...

Keyword(s):

Reaction Rate ◽

Main Sequence ◽

Light Element ◽

Reaction Rates ◽

Big Bang ◽

Trojan Horse ◽

Electron Screening ◽

Activation Technique ◽

Light Elements ◽

Trojan Horse Method

Light elements offer a unique opportunity for studying several astrophysical scenarios from Big Bang Nucleosynthesis to stellar physics. Understanding the stellar abundances of light elements is key to obtaining information on internal stellar structures and mixing phenomena in different evolutionary phases, such as the pre-main-sequence, main-sequence or red-giant branch. In such a case, light elements, i.e., lithium, beryllium and boron, are usually burnt at temperatures of the order of 2–5 × 106 K. Consequently, the astrophysical S(E)-factor and the reaction rate of the nuclear reactions responsible for the burning of such elements must be measured and evaluated at ultra-low energies (between 0 and 10 keV). The Trojan Horse Method (THM) is an experimental technique that allows us to perform this kind of measurements avoiding uncertainties due to the extrapolation and electron screening effects on direct data. A long Trojan Horse Method research program has been devoted to the measurement of light element burning cross sections at astrophysical energies. In addition, dedicated direct measurements have been performed using both in-beam spectroscopy and the activation technique. In this review we will report the details of these experimental measurements and the results in terms of S(E)-factor, reaction rate and electron screening potential. A comparison between astrophysical reaction rates evaluated here and the literature will also be given.

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On the fluorine nucleosynthesis in AGB stars in the light of the 19F(p,α)16O and 19F(α,p)22Ne reaction rate measured via THM

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194519600115 ◽

2019 ◽

Vol 49 ◽

pp. 1960011

Author(s):

S. Palmerini ◽

G. D’Agata ◽

M. La Cognata ◽

R. G. Pizzone ◽

I. Indelicato ◽

...

Keyword(s):

Experimental Data ◽

Reaction Rate ◽

State Of The Art ◽

Reaction Rates ◽

Asymptotic Giant Branch ◽

Asymptotic Giant Branch Stars ◽

Agb Stars ◽

Stellar Nucleosynthesis ◽

Trojan Horse Method ◽

Giant Branch Stars

In the last years the [Formula: see text]O and the [Formula: see text]F([Formula: see text],p)[Formula: see text]Ne reactions have been studied via the Trojan Horse Method in the energy range of interest for astrophysics. These are the first experimental data available for the main channels of [Formula: see text]F destruction that entirely cover the energy regions typical of the stellar H- and He- burning. In both cases the reaction rates are significantly larger than the previous estimations available in the literature. We present here a re-analysis of the fluorine nucleosynthesis in Asymptotic Giant Branch stars by employing in state-of-the-art models of stellar nucleosynthesis the THM reaction rates for [Formula: see text]F destruction.

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