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In this paper we investigate the deeply virtual Compton scattering (DVCS) process in electron–ion collisions at the Electron–Ion Collider (EIC) and Large Hadron Electron Collider (LHeC). The coherent and incoherent DVCS cross sections and differential distributions are estimated considering the possible states of nucleon configurations in the nuclear wave function and taking into account of the nonlinear corrections to the QCD dynamics. The impact of the nonlinear (saturation) effects is estimated. Our results indicate that a future experimental analysis of these processes can shed light on the description of the QCD dynamics at high energies. [ABSTRACT FROM AUTHOR]

Positron initiated deeply virtual Compton scattering (DVCS) off 4 He and 3 He nuclei is described. The way the so-called d - term could be obtained from the real part of the relevant Compton form factor is summarized, and the importance and novelty of this measurement is discussed. The measurements addressed for 3 He targets could be very useful even in a standard unpolarized target setup, measuring beam spin and beam charge asymmetries only. The unpolarized beam charge asymmetries for DVCS off 3 He and 4 He are also estimated, at JLab kinematics and, for 4 He, also at a configuration typical at the future Electron–Ion Collider. Incoherent DVCS processes, in particular the ones with tagging the internal target by measuring slow recoiling nuclei, and the unique possibility offered by positron beams for the investigation of Compton form factors of higher twist, are also briefly addressed. [ABSTRACT FROM AUTHOR]

The impact of potential future measurements of beam charge asymmetries on the current knowledge of Compton form factors is evaluated. Elaborating on the results of a global neural network fit to deeply virtual Compton scattering data, a Bayesian reweighting analysis quantifies the improved determination of the real part of the Compton form factor H . Such an improvement is particularly relevant for the experimental determination of the proton mechanical properties or for universality studies of generalized parton distributions through analyses of virtual Compton scattering in both spacelike and timelike regions. [ABSTRACT FROM AUTHOR]

Double Deeply Virtual Compton Scattering (DDVCS) is the only experimental channel for the determination of the dependence of the Generalized Parton Distributions (GPDs) on both the average and the transferred momentum independently. The physics observables of the electron induced di-muon production reaction e → ± p → e ± p μ + μ - off unpolarized hydrogen are discussed. Their measurement with the high luminosity and large acceptance SoLID spectrometer at the Thomas Jefferson National Accelerator Facility, using polarized and unpolarized positron and electron beams at 11 GeV is investigated. This experimental configuration is shown to provide unprecedented access to the GPDs with the determination of the real and imaginary parts of the Compton Form Factor H in an unexplored phase space, and to enable an exploratory investigation of higher twist effects. [ABSTRACT FROM AUTHOR]

Measuring DVCS on a neutron target is a necessary step to deepen our understanding of the structure of the nucleon in terms of Generalized Parton Distributions (GPDs). The combination of DVCS observables on neutron and proton targets allows to perform a flavor decomposition of the Compton Form Factors (CFFs), which are related to integrals of GPDs. Moreover, neutron-DVCS plays a complementary role to DVCS on a transversely polarized proton target in the determination of the CFF of the GPD E, the least known and constrained GPD that enters Ji's angular momentum sum rule. A measurement of the beam-charge asymmetry (BCA) in the e ± d → e ± n γ (p) reaction can significantly impact the experimental determination of the real CFFs of the E and, to a lesser extent, H ~ CFFs. [ABSTRACT FROM AUTHOR]