A new strategy for probing the Majorana neutrino CP violating phases and masses

TL;DR

This paper introduces a novel method to detect Majorana neutrino CP-violating phases and masses by analyzing neutrino-antineutrino oscillations in pion decays, providing new experimental bounds.

Contribution

It proposes a new strategy using neutrino-antineutrino oscillations in pion decays to probe Majorana neutrino properties, including CP phases and effective mass.

Findings

Derived a new bound on the effective muon-neutrino mass.

Showed that long baseline experiments are optimal for probing Majorana phases.

Utilized MINOS data to constrain neutrino properties.

Abstract

We propose a new strategy for detecting the CP-violating phases and the effective mass of muon Majorana neutrinos by measuring observables associated with neutrino-antineutrino oscillations in $\pi^{\pm}$ decays. Within the generic framework of quantum field theory, we compute the non-factorizable probability for producing a pair of same-charged muons in $\pi^{\pm}$ decays as a distinctive signature of $\nu_{\mu}-\bar{\nu_{\mu}}$ oscillations. We show that an intense neutrino beam through a long baseline experiment is favored for probing the Majorana phases. Using the neutrino-antineutrino oscillation probability reported by MINOS collaboration, a new stringent bound on the effective muon-neutrino mass is derived.