Measurement of Azimuthal Asymmetries With Respect To Both Beam Charge and Transverse Target Polarization in Exclusive Electroproduction of Real Photons

TL;DR

This paper reports the first measurement of azimuthal asymmetries in exclusive real photon electroproduction with respect to both beam charge and transverse target polarization, providing new insights into nucleon structure.

Contribution

It introduces the first measurement of azimuthal asymmetries relative to transverse target polarization and improves the precision of beam-charge asymmetry results, constraining quark angular momentum.

Findings

First measurement of asymmetries with respect to transverse target polarization.

Improved precision in beam-charge asymmetry measurements.

Constraints on quark angular momentum in the nucleon.

Abstract

Azimuthal asymmetries in exclusive electroproduction of real photons are measured for the first time with respect to transverse target polarisation, providing new constraints on Generalized Parton Distributions. From the same data set on a hydrogen target, new results for the beam-charge asymmetry are also extracted with better precision than those previously reported. By comparing model calculations with measured asymmetries attributed to the interference between the deeply virtual Compton scattering and Bethe-Heitler processes, a model-dependent constraint is obtained on the total angular momenta carried by up and down quarks in the nucleon.