Generalized parton distributions of valence, sea, and gluon components of the proton

TL;DR

This paper calculates the generalized parton distributions (GPDs) of the proton's valence quarks, sea quarks, and gluons using a light-front wave function approach, providing insights into the proton's internal structure at a low resolution scale.

Contribution

First-time evaluation of quark GPDs at nonzero skewness in both DGLAP and ERBL regions within the BLFQ framework, including gluon GPDs in the DGLAP region.

Findings

GPDs show qualitative similarity to global extraction but are smaller in magnitude.

Computed Compton form factors align with global analysis results.

Provides a realistic low-scale description of the nucleon structure.

Abstract

We compute the generalized parton distributions (GPDs) of valence quarks, sea quarks, and gluons in the proton using light-front wave functions obtained within the basis light-front quantization (BLFQ) framework, providing a realistic description of the nucleon at a low resolution scale. The wave functions are derived from a light-front QCD Hamiltonian without an explicit confining potential and include the three-quark, three-quark-gluon, and three-quark-quark-antiquark Fock sectors. For the first time within BLFQ, we evaluate quark GPDs at nonzero skewness in both the DGLAP and ERBL regions, while gluon GPDs are computed in the DGLAP region. The resulting GPDs exhibit qualitative features similar to, but smaller than the GUMP1.0 global extraction of GPDs based on experimental and lattice QCD data at next-to-leading order accuracy. We further compute the associated Compton form factors and obtain results consistent with the global analysis.