Deeply pseudoscalar meson electroproduction with CLAS and Generalized Parton Distributions

TL;DR

This paper analyzes recent CLAS data on exclusive pion electroproduction, showing the dominance of transverse amplitudes and interpreting results within the Generalized Parton Distribution framework, emphasizing the role of helicity-flip transversity GPDs.

Contribution

It demonstrates the importance of including helicity-flip transversity GPDs to interpret pion electroproduction data within the GPD formalism.

Findings

Cross sections are dominated by transverse amplitudes.

Data can be explained with GPDs including transversity components.

Helicity-flip GPDs are essential for accurate interpretation.

Abstract

We discuss the recent data of exclusive $\pi^0$ (and $\pi^+$) electroproduction on the proton obtained by the CLAS collaboration at Jefferson Lab. It is observed that the cross sections, which have been decomposed in $\sigma_T +\epsilon\sigma_L$, $\sigma_{TT}$ and $\sigma_{LT}$ structure functions, are dominated by transverse amplitude contributions. The data can be interpreted in the Generalized Parton Distribution formalism provided that one includes helicity-flip transversity GPDs.