Semi-dileptonic decays of the light vector mesons in Light Front Quark Model

TL;DR

This paper calculates transition form factors and decay branching ratios for light vector mesons decaying into pseudoscalar mesons and lepton pairs using the light-front quark model, matching existing data and predicting new decay rates.

Contribution

The study applies the light-front quark model to compute transition form factors and decay rates for vector to pseudoscalar meson decays, providing both data fit and new predictions.

Findings

Numerical results agree with experimental data for certain decay modes.

Predicted branching ratios for several rare decay modes.

Provided theoretical predictions for unmeasured decay processes.

Abstract

We study the transition form factors of the light vector to pseudoscalar mesons as functions of the momentum transfer $q^2$ within the light-front quark model. With these form factors, we calculate the decay branching ratios of all possible modes for $V\to P\ell^+\ell^-$ ($V=\omega$ and $\phi$, $P=\pi^0$, $\eta$ and $\eta^{\prime}$ and $\ell=e$ and $\mu$). We find that our numerical results fit with the data, such as those of $\omega \to \pi^0 \ell^+\ell^-$ and $\phi\to \pi^0 e^+e^-$ by NA60 and $\phi \to\eta e^+e^-$ by SND. We also predict that the branching ratios of $\phi \to \pi^0 \mu^+\mu^-$, $\omega\to \eta e^+e^-$, $\omega\to \eta \mu^+\mu^-$, $\phi\to \eta \mu^+\mu^-$ and $\phi\to \eta^{\prime} e^+e^-$ to be aroud $3.48\times 10^{-6}$, $3.22\times 10^{-6}$, $1.81\times 10^{-9}$, $6.86\times 10^{-6}$ $2.97\times 10^{-7}$, respectively.