Oscillation of heavy sterile neutrino in decay of $B \to \mu e \pi$

TL;DR

This paper explores how heavy sterile neutrino oscillations can affect B meson decays, providing a new way to measure neutrino mass differences and CP violation effects in these processes.

Contribution

It introduces the potential to detect heavy neutrino oscillation effects in B meson decays, offering a novel method to measure neutrino parameters and CP violation.

Findings

Heavy neutrino oscillations can influence B decay processes.

Detection of oscillation effects allows measurement of neutrino mass differences.

Potential observation of CP violation effects in heavy neutrino sector.

Abstract

In a scenario with two almost mass degenerate heavy sterile Majorana neutrinos with a mass $\sim 1$ GeV, we present the semileptonic decay widths of heavy charged pseudoscalars such as $B$ mesons, either lepton-number-violating ($B^{\pm} \to \mu^{\pm} e^{\pm} \pi^{\mp}$), or lepton-number-conserving ($B^{\pm} \to \mu^{\pm} e^{\mp} \pi^{\pm}$), mediated by such on-shell neutrinos. It had been explained in the literature that such decays may be eventually detected, and that they can present even detectable CP violation effects. In this work we point out that, in addition, such decays may present detectable effects of heavy neutrino oscillation, allowing us to extract the oscillation length and thus the heavy neutrino mass difference $\Delta M_N$, as well as a CP-violating Majorana phase.