Pion transition form factor in the Domain model of QCD vacuum

TL;DR

This paper investigates the pion transition form factor within the Domain model of QCD vacuum, showing its asymptotic behavior aligns with experimental trends but diverges from factorization theorem predictions.

Contribution

It introduces a calculation of the neutral pseudoscalar meson transition form factor considering vacuum configurations in the Domain model of QCD.

Findings

Supports Belle experimental trend for asymptotic form factor behavior

Finds divergence from factorization theorem predictions at high momentum transfer

Highlights influence of vacuum configurations on meson observables

Abstract

Domain model of QCD allows for description of wide range of meson observables, dynamical chiral symmetry breaking, and resolution of $U_A(1)$ and strong $CP$ problems. The purpose of the present study is transition form-factor of neutral pseudoscalar mesons, and how they are influenced by the typical vacuum configurations of the model -- almost everywhere homogeneous Abelian (anti-)self-dual fields. Asymptotic behavior of the calculated pion form-factor supports Belle trend, but the asymptotic value of $Q^2F_{\pi\gamma^*\gamma}$ differs from the prediction of factorization theorems.