Gauge invariance of DVCS off an arbitrary spin hadron: the deuteron target case

TL;DR

This paper derives a gauge invariant amplitude for deeply virtual Compton scattering (DVCS) off arbitrary spin hadrons, emphasizing a model-independent approach and applying it specifically to the deuteron, a spin-one hadron.

Contribution

It introduces a method to derive gauge invariant DVCS amplitudes for any spin hadron without relying on specific parametrizations, including an explicit case for the deuteron.

Findings

Derived gauge invariant amplitude for DVCS off spin-one hadron

Discussed single spin asymmetry using the new amplitude

Provided a model-independent framework for DVCS analysis

Abstract

Using twist 3 contributions and the relations, which emanate from the QCD equations of motion, we derive the gauge invariant amplitude for the deeply virtual Compton scattering (DVCS) off hadron with an arbitrary spin. We emphasize that our derivation is not based on a certain parametrization of the relevant hadron matrix elements of the quark(gluon) operators. As an application, we present the gauge invariant amplitude for the DVCS off spin-one hadron. Using the derived gauge invariant amplitude, the single spin asymmetry is discussed.