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arXiv · 2512.24358

Big Bang Nucleosynthesis results refined via the Trojan Horse Method

Roberta Spartà·Rosario Gianluca Pizzone·Livio Lamia·Alessandro Alberto Oliva·Marco La Cognata·Alessia Di Pietro·Pierpaolo Figuera·Giovanni Luca Guardo·Marco La Commara·Dario Lattuada·Marco Mazzocco·Sara Palmerini·Giuseppe Gabriele Rapisarda·Stefano Romano·Maria Letizia Sergi·Aurora Tumino
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Abstract

This work presents the Trojan Horse Method (THM) as a powerful technique for measuring nuclear reaction cross sections at astrophysical energies. We then explore the impact of THM-derived reaction rates on the predictions of Standard Big Bang Nucleosynthesis (SBBN) using the PRIMAT code. Primordial abundances are shown for the single rate impact and, for the first time, also for all the THM rates together. The result shows significant differences with the use of THM rates, which in some cases goes in the direction of improving the agreement with the observations with respect to the use of only reaction rates from direct data, especially for the $^7$Li and deuterium abundances, which are still open issues for SBBN.

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Roberta Spartà, Rosario Gianluca Pizzone, Livio Lamia, Alessandro Alberto Oliva, Marco La Cognata, Alessia Di Pietro, Pierpaolo Figuera, Giovanni Luca Guardo, Marco La Commara, Dario Lattuada, Marco Mazzocco, Sara Palmerini, Giuseppe Gabriele Rapisarda, Stefano Romano, Maria Letizia Sergi, Aurora Tumino. 2025-12-30. Big Bang Nucleosynthesis results refined via the Trojan Horse Method. https://arxiv.org/abs/2512.24358

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