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تسجيل مستخدم جديدDynamical evolution of critical fluctuations and its observation in heavy ion collisions
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We study time evolution of critical fluctuations of conserved charges near the QCD critical point in the context of relativistic heavy ion collisions. A stochastic diffusion equation is employed in order to describe the diffusion property of the critical fluctuation arising from the coupling of the order parameter field to conserved charges. We show that the diffusion property gives rise to a possibility of probing the early time fluctuations through the rapidity window dependence of the second-order cumulant and correlation function of conserved charges. It is pointed out that their non-monotonic behaviors as functions of the rapidity interval are robust experimental signals for the existence of the critical enhancement around the QCD critical point.
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This report summarizes the presentations and discussions during the Rapid Reaction Task Force Dynamics of critical fluctuations: Theory -- phenomenology -- heavy-ion collisions, which was organized by the ExtreMe Matter Institute EMMI and held at GSI
, Darmstadt, Germany in April 2019. We address the current understanding of the dynamics of critical fluctuations in QCD and their measurement in heavy-ion collision experiments. In addition, we outline what might be learned from studying correlations in other physical systems, such as cold atomic gases.
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