Orateur
Description
Generalized parton distributions (GPDs) are nucleon structure functions encoding longitudinal momentum and transverse position distributions of its constituent partons. In the zero-momentum-transfer limit ($t\rightarrow 0$), they provide access to fundamental mechanical and spin properties, in particular, the nucleon internal pressure distribution. Experimentally, GPDs can be probed through the electroproduction of a real photon via Deeply Virtual Compton Scattering (DVCS), and more generally, through the electroproduction of a dilepton pair via Double Deeply Virtual Compton Scattering (DDVCS). Using data from the CLAS12 spectrometer at Jefferson Lab, we report new Beam-Spin Asymmetry measurements of DVCS on the proton at small momentum transfer. Enabled by machine-learning techniques, these results extend the accessible kinematic range toward the $t\rightarrow 0$ limit, provide precise measurements over a broad kinematic range, and help constraining the proton’s pressure distribution through global fits. Finally, prospective measurements of DDVCS are discussed in the context of forthcoming experiments using polarized electron beams at Jefferson Lab and the future Electron-Ion Collider, highlighting their sensitivity to different GPD contributions and parametrizations.
| Working Group | WG1. Nucleons and Hadrons |
|---|---|
| Type of oral contribution | Experiment |