Beam Charge Asymmetries for Deeply Virtual Compton Scattering on the Proton at CLAS12

The parameterization of the nucleon structure through Generalized Parton Distributions (GPDs) shed a new light on the nucleon internal dynamics. For its direct interpretation, Deeply Virtual Compton Scattering (DVCS) is the golden channel for GPDs investigation. The DVCS process interferes with the Bethe-Heitler (BH) mechanism to constitute the leading order amplitude of the \(eN \to eN\gamma\) process. The study of the \(ep\gamma\) reaction with polarized positron and electron beams gives a complete set of unique observables to unravel the different contributions to the \(ep \gamma\) cross section. This separates the different reaction amplitudes, providing a direct access to their real and imaginary parts which procures crucial constraints on the model dependences and associated systematic uncertainties on GPDs extraction. The real part of the BH-DVCS interference amplitude is particularly sensitive to the \(D\)-term which parameterizes the Gravitational Form Factors of the nucleon. The separation of the imaginary parts of the interference and DVCS amplitudes provides insights on possible higher-twist effects. We propose to measure the unpolarized and polarized Beam Charge Asymmetries (BCAs) of the \(\vec{e}^{\pm}p \to e^{\pm}p \gamma\) process on an unpolarized hydrogen target with {\tt CLAS12}, using polarized positron and electron beams at 10.6 GeV. The azimuthal and \(t\)-dependences of the unpolarized and polarized BCAs will be measured over a large \((x_B,Q^2)\) phase space using a 100 day run with a luminosity of 0.66\(\times 10^{35}\)cm\(^{-2}\cdot\)s\(^{-1}\).