Single spin asymmetry in DVCS

TL;DR

This paper estimates the single spin asymmetry in deeply virtual Compton scattering (DVCS), providing a way to test theoretical predictions and access skewed parton distributions at small x in the DGLAP region, especially relevant for HERA experiments.

Contribution

It offers the first estimation of the single spin asymmetry in DVCS that can test amplitude ratios and access skewed parton distributions at small x.

Findings

Single spin asymmetry in DVCS is predicted to be large at HERA kinematics.

The asymmetry measurement can test the ratio of imaginary parts of amplitudes in DIS and DVCS.

Results suggest upcoming polarized electron experiments can observe these asymmetries.

Abstract

In the following note, we will present an estimation of the single spin asymmetry in deeply virtual Compton scattering (DVCS) which directly allows one to test predictions of the ratio of the imaginary part of the amplitude in DIS to DVCS, as well as access the skewed parton distributions at small $x$ in the DGLAP region. We find it to be large for the HERA kinematics to be accessible in forthcoming runs with polarized electrons.