Group velocity of neutrino waves

TL;DR

This paper refines the analysis of neutrino wave packets to investigate superluminal propagation, concluding it is possible only in a narrow parameter space and cannot explain the OPERA results.

Contribution

It introduces wave packet analysis into neutrino oscillation models with realistic parameters, refining previous superluminal propagation predictions.

Findings

Superluminal neutrino propagation is possible in a narrow parameter space.

Realistic mixing parameters drastically reduce observable superluminal effects.

The OPERA result cannot be explained within this wave packet framework.

Abstract

We follow up on the analysis of Mecozzi and Bellini (arXiv:1110:1253v1) where they showed, in principle, the possibility of superluminal propagation of neutrinos, as indicated by the recent OPERA result. We refine the analysis by introducing wave packets for the superposition of energy eigenstates and discuss the implications of their results with realistic values for the mixing and mass parameters in a full three neutrino mixing scenario. Our analysis shows the possibility of superluminal propagation of neutrino flavour in a very narrow range of neutrino parameter space. Simultaneously this reduces the number of observable events drastically. Therefore, the OPERA result cannot be explained in this frame-work.