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arXiv · 1212.1008

Event-by-event distributions of azimuthal asymmetries in ultrarelativistic heavy-ion collisions

H. Niemi·G. S. Denicol·H. Holopainen·P. Huovinen
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Abstract

Relativistic dissipative fluid dynamics is a common tool to describe the space-time evolution of the strongly interacting matter created in ultrarelativistic heavy-ion collisions. For a proper comparison to experimental data, fluid-dynamical calculations have to be performed on an event-by-event basis. Therefore, fluid dynamics should be able to reproduce, not only the event-averaged momentum anisotropies, $ $, but also their distributions. In this paper, we investigate the event-by-event distributions of the initial-state and momentum anisotropies $\epsilon_n$ and $v_n$, and their correlations. We demonstrate that the event-by-event distributions of relative $v_n$ fluctuations are almost equal to the event-by-event distributions of corresponding $\epsilon_n$ fluctuations, allowing experimental determination of the relative anisotropy fluctuations of the initial state. Furthermore, the correlation $c(v_2,v_4)$ turns out to be sensitive to the viscosity of the fluid providing an additional constraint to the properties of the strongly interacting matter.

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H. Niemi, G. S. Denicol, H. Holopainen, P. Huovinen. 2012-12-05. Event-by-event distributions of azimuthal asymmetries in ultrarelativistic heavy-ion collisions. https://doi.org/10.1103/physrevc.87.054901

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