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DOE OSTI · 2583735

Directed flow from parton spin-orbit coupling in $pp$ and $pA$ collisions

Benić, Sanjin [Univ. of Zagreb (Croatia)] (ORCID:0000000256370444)·Hatta, Yoshitaka [Brookhaven National Laboratory (BNL), Upton, NY (United States)]
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Abstract

We point out a novel mechanism to generate cos φ two-particle azimuthal correlation (‘directed flow’) in unpolarized proton-proton and proton-nucleus collisions in the forward rapidity region of the projectile proton. This is a direct consequence of the recently discovered strong spin-orbit coupling in gluons at small-x. The observable simultaneously serves as a unique probe into the double helicity parton distribution functions of the proton.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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BibTeXRIS

Benić, Sanjin [Univ. of Zagreb (Croatia)] (ORCID:0000000256370444), Hatta, Yoshitaka [Brookhaven National Laboratory (BNL), Upton, NY (United States)]. 2025-07-04. Directed flow from parton spin-orbit coupling in $pp$ and $pA$ collisions. https://doi.org/10.1016/j.physletb.2025.139709

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