A practical guide to unravel time-like transition form factors

TL;DR

This paper presents a practical method to determine properties of vector mesons by analyzing decay rates and cross sections, using a combination of vector meson dominance, quark-counting rules, and dispersion relations.

Contribution

It introduces a comprehensive approach to extract time-like transition form factors of vector mesons from experimental data, integrating multiple theoretical constraints.

Findings

Effective parametrization of transition form factors up to 4 GeV

Accurate extraction of meson masses, widths, and couplings

Consistency with theoretical models and experimental data

Abstract

A method to determine masses, widths and coupling constants of vector mesons, like phi(1020), omega(782) and rho0(770) recurrences is defined. Starting from data on decay rates and cross sections for the processes: phi -> M_I gamma, phi -> M_I e+e- and e+e- -> M_I phi, where M_I is a pseudoscalar or scalar meson with isospin I=0,1, the time-like transition form factors, which describe the vertex phi-gamma-M_I, are parametrized using a vector meson-propagators description in the low energy region <3-4 GeV, the quark-counting rule prescription for the high energy behavior, and the analyticity imposed by means of the dispersion relations.