Deconvolution problem of deeply virtual Compton scattering

Generalized parton distributions are instrumental to study both the three-dimensional structure and the energy-momentum tensor of the nucleon, and motivate numerous experimental programs involving hard exclusive measurements. Based on a next-to-leading order analysis and a careful study of evolution effects, we exhibit nontrivial generalized parton distributions with arbitrarily small imprints on deeply virtual Compton scattering observables. This means that in practice the reconstruction of generalized parton distributions from measurements, known as the deconvolution problem, does not possess a unique solution for this channel. In this paper we discuss the consequences on the extraction of generalized parton distributions from data and advocate for a multichannel analysis.

Automated summary

Generalized parton distributions are crucial for studying the structure of nucleons, but the reconstruction of them from measurements does not have a unique solution, advocating for a multichannel analysis.