Transversity in exclusive electroproduction of pseudoscalar mesons

TL;DR

This paper analyzes exclusive pseudoscalar meson electroproduction using the handbag approach, highlighting the significant role of transversely polarized photons and transversity GPDs, with results aligning well with recent experimental data.

Contribution

It introduces a novel analysis of pseudoscalar meson electroproduction emphasizing transversity GPDs and twist-3 wave functions within the handbag framework.

Findings

Transversely polarized photons significantly contribute to pion electroproduction.

The handbag approach accurately predicts cross sections and asymmetries.

Pi0 cross section is dominated by gamma_T -> pion transitions.

Abstract

In this talk it is reported on an analysis of hard exclusive electroproduction of pseudoscalar mesons within the handbag approach. It is argued that recent measurements of pion electroproduction performed by HERMES and CLAS clearly indicate the occurence of strong contributions from transversely polarized photons. Within the handbag approach such transitions are described by the transversity GPDs accompanied by twist-3 pion wave functions. It is shown that this handbag approach leads to results on cross sections and single-spin asymmetries in fair agreement with experiment. The surprising result is that the pi0 cross section is dominated by gamma_T -> pion transitions. Predictions for other pseudoscalar meson channels are also discussed.