Anomalous quark-gluon chromomagnetic interaction and high energy $\rho$-meson electroproduction

TL;DR

This paper investigates how a large anomalous quark chromomagnetic moment, arising from non-perturbative QCD effects, influences $ ho$-meson electroproduction, providing a better understanding of non-perturbative contributions at low $Q^2$.

Contribution

It introduces a new non-perturbative quark-gluon interaction mechanism that significantly impacts $ ho$-meson electroproduction cross sections, complementing traditional perturbative approaches.

Findings

Non-perturbative contribution improves data description at low $Q^2$ for transverse polarization.

The model partially explains experimental data but shows discrepancies for longitudinal polarization.

The anomalous chromomagnetic moment plays a crucial role in exclusive meson production.

Abstract

It is shown that existence of a large anomalous chromomagnetic moment of quark induced by non-perturbative structure of QCD leads to the additional contribution to exclusive $\rho$-meson electroproduction off proton target. The significant contribution coming from new type of quark-gluon interaction to the $\rho $-meson production cross section for both transversal and longitudinal polarization of virtual photon is found. Such non-perturbative contribution together with conventional perturbative two-gluon exchange allows us to describe the experimental data at low $Q^2$ for transversal polarization. However, in the longitudinal polarization case there is still some discrepancy with the data. The possible source of this deviation is discussed.