Matter effects on the flavor conversions of solar neutrinos and high-energy astrophysical neutrinos

TL;DR

This paper investigates matter effects on neutrino flavor conversions from the Sun and Moon, finding lunar effects are minimal but solar effects on high-energy neutrinos can be significant yet hard to observe.

Contribution

It highlights the suppressed lunar matter effects on solar neutrinos and emphasizes the potential significance of solar matter effects on high-energy astrophysical neutrinos.

Findings

Lunar matter effects on solar neutrinos are suppressed by 1.2%.

Matter effects on high-energy neutrinos passing through the Sun can be significant.

Observing these effects remains challenging with next-generation detectors.

Abstract

Can we observe the solar eclipses in the neutrino light? In principle, this is possible by identifying the lunar matter effects on the flavor conversions of solar neutrinos when they traverse the Moon before reaching the detectors at the Earth. Unfortunately, we show that the lunar matter effects on the survival probability of solar $^8{\rm B}$ neutrinos are suppressed by an additional factor of $1.2\%$, compared to the day-night asymmetry. However, we point out that the matter effects on the flavor conversions of high-energy astrophysical neutrinos, when they propagate through the Sun, can be significant. Though the flavor composition of high-energy neutrinos can be remarkably modified, it is quite challenging to observe such effects even in the next-generation of neutrino telescopes.