Leptoquarks in FCNC charm decays

TL;DR

This paper investigates how scalar leptoquarks could influence charm meson decays, potentially explaining discrepancies in decay constants and affecting rare decay processes, with implications for new physics beyond the Standard Model.

Contribution

It analyzes the impact of scalar leptoquarks on charm meson decay observables, providing new insights into their role in flavor-changing neutral currents.

Findings

Leptoquarks can modify the dilepton mass distribution in D^+ --> pi^+ mu^+ mu^- decays.

Leptoquarks can alter the branching ratios of D^0 --> mu^+ mu^- decays.

Constraints on leptoquark parameters from existing experimental data.

Abstract

Recently it was noticed that among many scenarios of new physics leptoquarks might compensate for the disagreement between the lattice and experimental results for the charmed strange meson decay constant. The leptoquarks might modify also the flavor changing neutral current charm decays. In this study we investigate impact of the scalar leptoquark with electric charge -1/3 on the dilepton invariant mass distribution in the D^+ --> pi^+ mu^+ mu^- decay and on the branching ratios of the D^0 --> mu^+ mu^- using the existing experimental results.