Deconvolution problem of deeply virtual Compton scattering

Authors :: H. Dutrieux
C. Mezrag
Hervé Moutarde
P. Sznajder
V. Bertone
Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU)
Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay
Source :: Phys.Rev.D, Phys.Rev.D, 2021, 103 (11), pp.114019. ⟨10.1103/PhysRevD.103.114019⟩, Physical Review D, Physical Review D, American Physical Society, 2021, 103 (11), pp.114019. ⟨10.1103/PhysRevD.103.114019⟩, Physical Review
Publication Year :: 2021
Publisher :: American Physical Society (APS), 2021.
Abstract: Generalised parton distributions are instrumental to study both the three-dimensional structure and the energy-momentum tensor of the nucleon, and motivate numerous experimental programmes involving hard exclusive measurements. Based on a next-to-leading order analysis and a careful study of evolution effects, we exhibit non-trivial generalised parton distributions with arbitrarily small imprints on deeply virtual Compton scattering observables. This means that in practice the reconstruction of generalised parton distributions from measurements, known as the deconvolution problem, does not possess a unique solution for this channel. In this Letter we discuss the consequences on the extraction of generalised parton distributions from data and advocate for a multi-channel analysis.<br />Comment: 7 pages, 2 figures