Solar Neutrino Matter Effects Redux

TL;DR

This paper reevaluates solar neutrino data to understand matter effects in the Sun, highlighting limitations in constraining the mixing angle θ13 and the potential for Standard Model effects to imitate new physics signals.

Contribution

It demonstrates that current solar neutrino data poorly constrain θ13 and that Standard Model effects can mimic signals of physics beyond the Standard Model.

Findings

Solar neutrino data weakly constrains θ13

Standard Model effects can imitate new physics signals

Revised analysis of matter effects in the Sun

Abstract

Following recent low-threshold analysis of the Sudbury Neutrino Observatory and asymmetry measurements of the BOREXINO Collaboration of the solar neutrino flux, we revisit the analysis of the matter effects in the Sun. We show that solar neutrino data constrains the mixing angle $\theta_{13}$ poorly and that subdominant Standard Model effects can mimic the effects of the physics beyond the Standard Model.