- Open Access
Causally connected regions in relativistic heavy ion collisions
Phys. Rev. C 114, 044909 – Published 27 October, 2026
DOI: https://doi.org/10.1103/9gxh-spl6
Abstract
Quantifying causal connections within fireballs resulting from high energy nucleus-nucleus collisions is pertinent to assessing the viability of several proposed mechanisms that directly influence particle production and correlations. Fireball causal connections have previously been studied in the context of dimensional Bjorken flow. We expand into dimensions using Gubser flow, which includes transverse expansion. Our findings suggest that the volume of these causally connected fireballs are on the order of 10–100 for observables dependent on the formation of the light quark condensates, but could be larger for other observables.
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