Do Neutrino Wave Functions Overlap and Does it Matter?

TL;DR

This paper investigates whether neutrino wave functions overlap and if such overlap affects their physical behavior, finding that typical experimental neutrinos can be treated as non-overlapping despite potential overlaps in astrophysical contexts.

Contribution

The study challenges the common assumption of ignoring anti-symmetrization by analyzing neutrino wave packet evolution, showing that overlaps are negligible for most practical experiments.

Findings

Accelerator and reactor neutrinos can be treated as separate wave packets.

Solar and supernova neutrinos may have overlapping wave functions but can still be analyzed as non-overlapping.

Anti-symmetrization effects are negligible in typical neutrino detection scenarios.

Abstract

Studies of neutrinos commonly ignore anti-symmetrization of their wave functions. This implicitly assumes that either spatial wave functions for neutrinos with approximately the same momentum do not overlap or their overlapping has no measurable consequences. We examine these assumptions by considering the evolution of three-dimensional neutrino wave packets (WPs). We find that it is perfectly adequate to treat accelerator and reactor neutrinos as separate WPs for typical experimental setup. While solar and supernova neutrinos correspond to overlapping WPs, they can be treated effectively as non-overlapping for analyses of their detection.