Quark and gluon tomography of the helium-4 nucleus

TL;DR

This paper uses QCD collinear factorization to perform the first 3D tomography of a light nucleus, helium-4, by analyzing elastic form factors and deeply virtual Compton scattering with high theoretical precision.

Contribution

It introduces a novel approach to nuclear tomography by constraining generalized parton distributions at next-to-leading order with comprehensive corrections.

Findings

Revealed distinct transverse spatial distributions of quarks and gluons in helium-4.

Achieved unprecedented theoretical precision in nuclear tomography.

Provided the first detailed 3D structure of a light nucleus.

Abstract

QCD collinear factorization allows coherent hard exclusive reactions to reveal the quark-gluon structure of light nuclei, enabling their 3D tomography. We study elastic form factors and deeply virtual Compton scattering on a helium-4 target, achieving theoretical precision unprecedented even in proton studies. Constraining generalized parton distributions at next-to-leading order in $\alpha_s$, incorporating kinematic twist corrections, and using full evolution equations, we provide the first tomography of a light nucleus, revealing distinct transverse spatial distributions of quarks and gluons.