# Polynomiality sum rules for generalized parton distributions of spin-1 targets

## TL;DR

This paper derives polynomiality sum rules for all leading-twist quark and gluon GPDs of spin-1 targets, linking Mellin moments to polynomials in skewness with form factors as coefficients.

## Contribution

It provides the first comprehensive derivation of polynomiality sum rules for all leading-twist GPDs of spin-1 targets, including decompositions of local currents.

## Key findings

- Sum rules connect Mellin moments to skewness polynomials.
- Decomposition of local currents into generalized form factors.
- Applicable to spin-1 targets like the deuteron.

## Abstract

We present the polynomiality sum rules for all leading-twist quark and gluon generalized parton distributions (GPDs) of spin-1 targets such as the deuteron nucleus. The sum rules connect the Mellin moments of these GPDs to polynomials in skewness parameter $\xi$, which contain generalized form factors (GFFs) as their coefficients. The decompositions of local currents in terms of generalized form factors for spin-1 targets are obtained as a byproduct of this derivation.