Solar fusion III: New data and theory for hydrogen-burning stars

TL;DR

This review summarizes recent advances in nuclear reaction data and theory crucial for modeling hydrogen-burning stars, driven by high-precision solar neutrino measurements and encompassing experimental, theoretical, and observational perspectives.

Contribution

It provides an updated evaluation of nuclear reaction rates, uncertainties, and related astrophysical factors essential for the standard solar model, based on recent experimental and theoretical progress.

Findings

Improved precision in proton-proton chain neutrino flux measurements.

Updated recommended astrophysical S-factors for key reactions.

Analysis of electron screening and radiative opacity impacts on solar models.

Abstract

In stars that lie on the main sequence in the Hertzsprung-Russel diagram, like our sun, hydrogen is fused to helium in a number of nuclear reaction chains and series, such as the proton-proton chain and the carbon-nitrogen-oxygen cycles. Precisely determined thermonuclear rates of these reactions lie at the foundation of the standard solar model. This review, the third decadal evaluation of the nuclear physics of hydrogen-burning stars, is motivated by the great advances made in recent years by solar neutrino observatories, putting experimental knowledge of the proton-proton chain neutrino fluxes in the few-percent precision range. The basis of the review is a one-week community meeting held in July 2022 in Berkeley, California, and many subsequent digital meetings and exchanges. The relevant reactions of solar and stellar hydrogen burning are reviewed here, from both theoretical and experimental perspectives. Recommendations for the state of the art of the astrophysical S-factor and its uncertainty are formulated for each of them. Several other topics of paramount importance for the solar model are reviewed, as well: recent and future neutrino experiments, electron screening, radiative opacities, and current and upcoming experimental facilities. In addition to reaction-specific recommendations, also general recommendations are formed.