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DOE OSTI · 2516760

Exploring orbital angular momentum and spin-orbit correlations for gluons at the Electron-Ion Collider

Bhattacharya, Shohini (ORCID:000000018536082X)·Boussarie, Renaud (ORCID:0000000317904885)·Hatta, Yoshitaka (ORCID:0000000168803238)
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Abstract

In our previous work [S. Bhattacharya , ], we introduced a pioneering observable aimed at experimentally detecting the orbital angular momentum (OAM) of gluons. Our focus was on the longitudinal double spin asymmetry observed in exclusive dijet production during electron-proton scattering. We demonstrated the sensitivity of the cos ϕ angular correlation between the scattered electron and proton as a probe for gluon OAM at small x and its intricate interplay with gluon helicity. This current work provides a comprehensive exposition, diving further into the aforementioned calculation with added elaboration and in-depth analysis. We reveal that, in addition to the gluon OAM, one also gains access to the spin-orbit correlation of gluons. We supplement our work with a detailed numerical analysis of our observables for the kinematics of the Electron-Ion Collider. In addition to dijet production, we also consider the recently proposed semi-inclusive diffractive deep inelastic scattering process, which potentially offers experimental advantages over dijet measurements. Finally, we investigate quark-channel contributions to these processes and find an unexpected breakdown of collinear factorization. Published by the American Physical Society 2025

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Bhattacharya, Shohini (ORCID:000000018536082X), Boussarie, Renaud (ORCID:0000000317904885), Hatta, Yoshitaka (ORCID:0000000168803238). 2025-02-13. Exploring orbital angular momentum and spin-orbit correlations for gluons at the Electron-Ion Collider. https://doi.org/10.1103/physrevd.111.034019

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