Lorentz noninvariant oscillations of massless neutrinos are excluded

TL;DR

This paper evaluates Lorentz noninvariant neutrino oscillation models without neutrino masses, finding that none can simultaneously explain atmospheric, solar, and KamLAND neutrino data.

Contribution

It systematically analyzes all 19 possible Lorentz noninvariant Hamiltonian structures within the Standard Model Extension, ruling out models that fit all neutrino data.

Findings

No Lorentz noninvariant model with 1/E dependence fits all neutrino data

Bicycle model cannot simultaneously explain atmospheric and solar neutrino observations

Direction-independent models are insufficient to account for the full range of neutrino oscillation data

Abstract

The bicycle model of Lorentz noninvariant neutrino oscillations without neutrino masses naturally predicts maximal mixing and a 1/E dependence of the oscillation argument for muon-neutrino to tau-neutrino oscillations of atmospheric and long-baseline neutrinos, but cannot also simultaneously fit the data for solar neutrinos and KamLAND. Within the Standard Model Extension, we examine all 19 possible structures of the effective Hamiltonian for Lorentz noninvariant oscillations of massless neutrinos that naturally have a 1/E dependence at high neutrino energy. Due to the lack of any evidence for direction dependence, we consider only direction-independent oscillations. Although we find a number of models with a 1/E dependence for atmospheric and long-baseline neutrinos, none can also simultaneously fit solar and KamLAND data.