VEP oscillation solutions to the solar neutrino problem

TL;DR

This paper investigates how violations of the equivalence principle could explain the solar neutrino problem through VEP-induced oscillations, offering solutions involving matter effects and vacuum oscillations, and predicts seasonal neutrino flux variations.

Contribution

It introduces a VEP-based framework for neutrino oscillations, providing new constraints and identifying two possible oscillation solutions for the solar neutrino problem.

Findings

Two oscillation solutions consistent with data

VEP parameters constrained by current measurements

Prediction of semi-annual neutrino flux variation

Abstract

We study the solar neutrino problem within the framework of a parametrized post-Newtonian formulation for the gravitational interaction of the neutrinos, which incorporates a violation to the equivalence principle (VEP). Using the current data on the rates and the energy spectrum we find two possible oscillation solutions, both for a large mixing angle. One of them involves the MSW effect in matter and the other corresponds to vacuum oscillations. An interesting characteristic of this mechanism is that it predicts a semi-annual variation of the neutrino flux. Our analysis provides new constraints for some VEP parameters.