Lepton flavour violating pion decay pi^+ --> mu^- nu_\mu e^+ e^+ and the SU(3)_C X SU(3)_L X U(1) model

TL;DR

This paper calculates the lepton-flavour-violating decay of a pion within an extended SU(3)_C x SU(3)_L x U(1)_N model, finding a branching ratio well below experimental limits, thus constraining new physics scenarios.

Contribution

It provides a calculation of a rare pion decay in a specific extended gauge model without assuming lepton mixing, extending previous results by including the model's effects.

Findings

Branching ratio is much smaller than experimental upper limit.

Results align with previous calculations when anomalous interactions are neglected.

Supports constraints on lepton-flavour violation in extended gauge models.

Abstract

In the framework of the minimal ${SU}(3)_C\otimes {SU}(3)_L \otimes {U}(1)_N$ model, the lepton-flavour-violating decay $\pi^+ \ra \mu^- \nu_\mu e^+ e^+ $ is calculated without directly invoking lepton mixing. The branching ratio for this rare pion decay mode is found to be much smaller than the current experimental upper limit. Dropping out anomalous interactions, this result coincides with the previous calculation .