First CLAS12 measurement of DVCS beam-spin asymmetries in the extended valence region

TL;DR

This paper reports the first measurement of DVCS beam-spin asymmetries in the extended valence region using CLAS12, significantly expanding the kinematic range and providing a large dataset to constrain nucleon structure models.

Contribution

It presents the first measurement of DVCS beam-spin asymmetries in the extended valence region with unprecedented data volume and precision, expanding the kinematic coverage beyond previous experiments.

Findings

Extended the $Q^2$ and Bjorken-$x$ phase space coverage.

Provided over 2000 new data points with high statistical precision.

Set new constraints for future GPD phenomenological models.

Abstract

Deeply virtual Compton scattering (DVCS) allows one to probe Generalized Parton Distributions (GPDs) describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarised protons. The results greatly extend the $Q^2$ and Bjorken-$x$ phase space beyond the existing data in the valence region and provide over 2000 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.