Investigating the impact of Solar Fusion III reaction rates on helioseismic constraints and solar neutrino fluxes

TL;DR

This study assesses how the new Solar Fusion III reaction rates influence solar models, helioseismic data, and neutrino flux predictions, revealing significant impacts and highlighting remaining discrepancies.

Contribution

It provides a comprehensive analysis of the effects of Solar Fusion III reaction rates on standard and non-standard solar models, including neutrino flux predictions and helioseismic constraints.

Findings

Solar Fusion III rates improve helioseismic model agreement slightly.

Use of SFIII rates lowers predicted neutrino fluxes for beryllium, boron, and CNO.

Changes within reaction rate uncertainties are insufficient to match observations.

Abstract

Nuclear reaction rates are crucial ingredients of solar and stellar models, they directly impact the duration of the life of stars and the energy they produce. In the solar case, the tight observational constraints put on models (Mass, Radius, Luminosity and chemical composition) coupled to our capabilities to probe the solar interior thanks to helioseismology and solar neutrinos provide an exquisite testbed for such physical ingredients. With the recent publication of the Solar Fusion III reaction rates, a new generation of solar models may be computed and put to the test. We aim to investigate the impact of the new Solar Fusion III reaction rates on solar models, both standard and non-standard, as well as the impact of the current uncertainties on some key solar reactions on the predicted neutrino fluxes for boron and the so-called CNO cycle. We compute various theoretical standard solar models as well as non-standard models reproducing the depletion of lithium and beryllium for various abundances, nuclear reaction rates and opacities. We focus on the impact of the solar fusion III reaction rates on both helioseismic inversion results and neutrino fluxes. We find that using the Solar Fusion III reaction rates significantly impact the agreement of solar models both with helioseismic constraints and neutrino flux measurements. While for helioseismic constraints it seems that there is a slight improvement, for neutrino fluxes, the use of the SFIII reaction rates induces a lowering of the beryllium, boron and CNO neutrino fluxes. When investigating the impact of changes on the rates of key reactions within their quoted uncertainties, we find that these changes are far from sufficient to reconcile models and observations, potentially hinting at other processes (e.g. planetary formation as found in other studies).