The spectroscopy of solar sterile neutrinos

TL;DR

This paper predicts the spectrum and flux of sterile neutrinos produced by solar nuclear reactions, assessing their detectability with future solar neutrino experiments using an updated solar model.

Contribution

It provides the first detailed predictions of solar sterile neutrino spectra and fluxes from key nuclear reactions based on a modern solar model.

Findings

Sterile neutrinos constitute 3-4% of solar neutrino flux.

The most intense sources are the pp and ^7Be reactions.

Predicted fluxes for various nuclear reactions are quantified.

Abstract

We predict the sterile neutrino spectrum of some of the key solar nuclear reactions and discuss the possibility of these being observed by the next generation of solar neutrino experiments. By using an up-to-date standard solar model with good agreement with current helioseismology and solar neutrino flux data sets, we found that from solar neutrino fluxes arriving on Earth only 3\%-4\% correspond to the sterile neutrino. The most intense solar sources of sterile neutrinos are the $pp$ and $^7Be$ nuclear reactions with a total flux of $2.2\times 10^{9}\;{\rm cm^2 s^{-1}}$ and $1.8\times 10^{8}\;{\rm cm^2 s^{-1}}$, followed by the $^{13}N$ and $^{15}O$ nuclear reactions with a total flux of $1.9\times 10^{7}\;{\rm cm^2 s^{-1}}$ and $1.7\times 10^{7}\;{\rm cm^2 s^{-1}}$. Moreover, we compute the sterile neutrino spectra of the nuclear proton-proton nuclear reactions -- $pp$, $hep$ and $^8B$ and the carbon-nitrogen-oxygen -- $^{13}N$, $^{15}O$ and $^{17}F$ and the spectral lines of $^7Be$.