Generalized Parton Distributions from Hadronic Observables

TL;DR

This paper introduces a physically motivated parametrization for unpolarized generalized parton distributions, H and E, that integrates experimental data and lattice calculations to enable a more model-independent extraction of these distributions.

Contribution

It presents a new parametrization method for GPDs that combines experimental and lattice data, improving upon previous mathematical ansatz approaches.

Findings

Successful fit to nucleon elastic form factors and structure functions

Constraints from lattice calculations at non-zero skewness

Advances towards model-independent GPD extraction

Abstract

We propose a physically motivated parametrization for the unpolarized generalized parton distributions, H and E, valid at both zero and non-zero values of the skewness variable, \zeta. At \zeta=0, H and E are determined using constraints from simultaneous fits of experimental data on both the nucleon elastic form factors and the deep inelastic structure functions. Lattice calculations of the higher moments constrain the parametrization at \zeta > 0. Our method provides a step towards a model independent extraction of generalized distributions from the data that is alternative to the mathematical ansatz of double distributions.