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arXiv · 2208.03186

Gluon gravitational form factors of protons from charmonium photoproduction

Xiao-Yun Wang·Fancong Zeng·Quanjin Wang
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Abstract

Inspired by the recent near-threshold $J/\psi$ photoproduction measurements, we discuss gluon gravitational form factors (GFFs) and internal properties of the proton. This work presents a complete analysis of the proton gluon GFFs connecting the gluon part of the energy-momentum tensor and the heavy quarkonium photoproduction. In particular, a global fitting of the $J/\psi$ differential and total cross section experimental data is used to determine the gluon GFFs as functions of the squared momentum transfer $t$. Combined with the quark contributions to the $D$-term form factor extracted from the deeply virtual Compton scattering experiment, the total $D$-term is obtained to investigate their applications in describing the proton mechanical properties. These studies provide a unique perspective on investigating the proton gluon GFFs and important information for enhancing QCD constraints on the gluon GFFs.

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Xiao-Yun Wang, Fancong Zeng, Quanjin Wang. 2022-08-05. Gluon gravitational form factors of protons from charmonium photoproduction. https://doi.org/10.1088/1674-1137%2Faccc1e

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