Transition GPDs and exclusive electroproduction of $\pi-\Delta(1232)$ final states

TL;DR

This paper models exclusive electroproduction of pions and Delta baryons using generalized parton distributions within the handbag approach, providing numerical predictions for cross sections in the large-Nc limit.

Contribution

It introduces the definition of p-Delta transversity GPDs and relates them to proton GPDs using large-Nc approximations, advancing the theoretical understanding of these processes.

Findings

Predicted partial cross sections for gamma* p to pi- Delta++

Defined p-Delta transversity GPDs and related them to proton GPDs

Incorporated quark transverse momenta and Sudakov effects in calculations

Abstract

We investigate exclusive electroproduction of $\pi^-\Delta^{++}$ within the handbag approach in which the helicity amplitudes factorize into generalized parton distributions (GPDs) and hard partonic subprocesses. We define the $p-\Delta$ transversity GPDs while the helicity non-flip GPDs are taken from the literature. For the numerical estimates of observables we utilize large-$N_C$ results in order to relate a few of the $p-\Delta$ GPDs to the proton-proton ones and neglect all other GPDs. In the calculation of the twist-2 and twist-3 subprocess amplitudes we take into account quark transverse momenta in combination with Sudakov suppressions. The partial cross sections for $\gamma^*p\to \pi^-\Delta^{++}$ are predicted in the large-$N_C$ limit.