A Continuum Schwinger Method to Study the Pion's Generalized Parton Distribution

TL;DR

This paper introduces a new algebraic modeling approach for pion GPDs that respects all QCD constraints and uses it to analyze DVCS processes, revealing gluon dominance at EIC energies.

Contribution

A novel continuum Schwinger method for modeling pion GPDs that inherently satisfies all fundamental QCD constraints.

Findings

Gluons dominate the pion response at EIC kinematics.

The model satisfies support, polynomiality, positivity, and the soft-pion theorem.

Next-to-leading order calculations of DVCS Compton Form Factors.

Abstract

Generalised Parton Distributions (GPDs) provide multidimensional insight into hadron structure and are particularly relevant for the pion, whose dynamics are intimately linked to chiral symmetry breaking. We introduce a novel modelling strategy for pion GPDs that satisfies all QCD constraints by construction: support, polynomiality, positivity, and the soft-pion theorem. The approach is illustrated with a simple algebraic model, which is evolved and used to compute deeply virtual Compton scattering (DVCS) Compton Form Factors at next-to-leading order. Our results indicate that gluons dominate the pion response at the Electron Ion Collider kinematics.