Oscillations of three neutrinos with all Delta m^2 approx 10^{-3} eV^2

TL;DR

This paper investigates the possibility of three-neutrino oscillations with mass splittings around 10^{-3} eV^2, showing they are compatible with existing solar and atmospheric neutrino data and discussing how future experiments could confirm or exclude this scenario.

Contribution

It demonstrates that three-neutrino oscillations with specific mass differences are consistent with current experimental results and highlights the potential for future experiments to detect or rule out this pattern.

Findings

Three-neutrino oscillations with ~10^{-3} eV^2 are compatible with solar and atmospheric data.

SuperKamiokande is insensitive to certain solar oscillations, allowing this pattern to remain viable.

Future solar experiments or KamLand could confirm or exclude this oscillation pattern.

Abstract

Oscillations of three neutrinos with all squared mass splittings around 10^{-3} eV^2 are not firmly excluded by solar neutrino experiments. We carefully verify that they are also perfectly compatible with atmospheric neutrino experiments: due to accidental reasons the SuperKamiokande experiment is rather insensitive to `solar' nu_e/\nu_mu oscillations, even if some characteristic small effects could become visible with more statistics. This pattern of oscillations can be excluded by new solar experiments, or cleanly discovered at KamLand. We also perform a fit of the most recent atmospheric SK data within the usual assumption that `solar' effects are negligible.