Mass-dependence of pseudoscalar meson elastic form factors

TL;DR

This paper uses a continuum approach to calculate the electromagnetic form factors of pion-like mesons with varying masses, comparing results with lattice-QCD and exploring the validity of hard-scattering formulas across different meson masses.

Contribution

It provides new calculations of meson form factors across a range of masses and compares them with lattice-QCD results, enhancing understanding of meson structure and QCD predictions.

Findings

Form factor of physical pion best tests hard-scattering formula

Verification capacity decreases with increasing meson mass

Results facilitate comparison with lattice-QCD calculations

Abstract

A continuum approach to quark-antiquark bound-states is used to determine the electromagnetic form factors of pion-like mesons with masses $m_{0^-}/{\rm GeV}=0.14$, $0.47$, $0.69$, $0.83$ on a spacelike domain that extends to $Q^2 \lesssim 10\,$GeV$^2$. The results enable direct comparisons with contemporary lattice-QCD calculations of heavy-pion form factors at large values of momentum transfer and aid in understanding them. They also reveal, inter alia, that the form factor of the physical pion provides the best opportunity for verification of the factorised hard-scattering formula relevant to this class of exclusive processes and that this capacity diminishes steadily as the meson mass increases.