A data-driven approach to $\pi^{0}, \eta$ and $\eta^{\prime}$ single and double Dalitz decays

TL;DR

This paper presents a data-driven method using rational approximants to predict dilepton spectra and branching ratios for single and double Dalitz decays of neutral mesons, based on experimental form factor data.

Contribution

It introduces a novel data-driven approach employing rational approximants to accurately model meson transition form factors for decay predictions.

Findings

Predicted dilepton invariant mass spectra for meson decays.

Calculated integrated branching ratios for various decay channels.

Validated the approach against existing experimental data.

Abstract

The dilepton invariant mass spectra and integrated branching ratios of the single and double Dalitz decays $\mathcal{P}\to\ell^{+}\ell^{-}\gamma$ and $\mathcal{P}\to\ell^{+}\ell^{-}\ell^{+}\ell^{-}$ ($\mathcal{P}=\pi^{0}, \eta, \eta^{\prime}$; $\ell=e$ or $\mu$) are predicted by means of a data-driven approach based on the use of rational approximants applied to $\pi^{0}, \eta$ and $\eta^{\prime}$ transition form factor experimental data in the space-like region.