On wide-angle photo- and electroproduction of pions to twist-3 accuracy

TL;DR

This paper investigates wide-angle pion photo- and electroproduction using the handbag mechanism, calculating subprocess amplitudes to twist-3 accuracy and comparing theoretical cross-sections with experimental data.

Contribution

It introduces a twist-3 level calculation of subprocess amplitudes including 2- and 3-body pion components within the handbag approach.

Findings

Calculated cross-sections show good agreement with experimental data.

Spin effects are analyzed within the twist-3 framework.

The approach incorporates generalized parton distributions in the analysis.

Abstract

The wide-angle photo- and electroproduction of pions is investigated within the handbag mechanism in which the $\gamma^{(*)} N\to \pi N'$ amplitudes factorize into subprocess amplitudes,$\gamma^{(*)} q\to \pi q'$, and form factors representing $1/x$-moments of generalized parton distributions (GPDs). The subprocess is calculated to twist-3 accuracy taking into account both the 2- and 3-body Fock components of the pion. The cross-sections are compared to experiment and spin-effects are discussed.