Studying nucleon structure via Double Deeply Virtual Compton Scattering (DDVCS)

Abstract

Study of the structure and dynamics of the nucleon has been deeply renewed with the advent of a parameterization of the partonic structure of the nucleon in terms of the Generalized Parton Distributions (GPDs). Encoding the correlations between the elementary constituents of the nucleon, GPDs allow a 3-dimensional imaging of the nucleon from the dynamical link between the transverse position and the longitudinal momentum of partons. Double Deeply Virtual Compton Scattering (DDVCS) corresponds to the scattering from the nucleon of a virtual photon that finally generates a lepton pair, where the final leptons can be either an electron or a muon pair. The virtuality of the final photon allows to investigate in a decorrelated way the initial and transferred momentum dependences of the GPDs. This unique feature of DDVCS is of relevance, among others, for the determination of the transverse parton densities and the distribution of nuclear forces. This proceeding discusses preliminary model-predicted DDVCS experimental projections at JLab12 and indicates the impact of potential DDVCS experiments.