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arXiv · 2609.26449

Non-Monotonicity of $p_{\rm T}$ Correlations in Au + Au Collisions at RHIC

Rutik Manikandhan
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Abstract

We report the first measurements of two-particle transverse momentum correlations for mid-rapidity charged particles in Au+Au collisions at $\sqrt{s_{\rm NN}} =$ 3.0, 3.2, 3.5, 3.9, 4.5, 5.2 and 7.7 GeV recorded by the STAR experiment. The results are compared with previous STAR measurements from the Beam Energy Scan Phase I (BES-I) and with transport model calculations. The measured two-particle $p_{\rm T}$ correlators exhibit an approximate power-law scaling with the number of participating nucleons ($N_{\rm part}$), consistent with expectations from an independent-source scenario. This scaling is least well described at the lowest collision energy, $\sqrt{s_{\rm NN}} = 3.0$~GeV. Furthermore, a non-monotonic energy dependence of the $p_{\rm T}$ correlations is observed in central collisions, representing the first systematic observation of such behavior as a function of collision energy.

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Rutik Manikandhan. 2026-09-22. Non-Monotonicity of $p_{\rm T}$ Correlations in Au + Au Collisions at RHIC. https://doi.org/10.1016/j.jspc.2026.100502

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