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arXiv · 1405.6595

Eccentricity distributions in nucleus-nucleus collisions

Li Yan·Jean-Yves Ollitrault·Arthur M. Poskanzer
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Abstract

We propose a new parametrization of the distribution of the initial eccentricity in a nucleus-nucleus collision at a fixed centrality, which we name the Elliptic Power distribution. It is a two-parameter distribution, where one of the parameters corresponds to the intrinsic eccentricity, while the other parameter controls the magnitude of eccentricity fluctuations. Unlike the previously used Bessel- Gaussian distribution, which becomes worse for more peripheral collisions, the new Elliptic Power distribution fits several Monte Carlo models of the initial state for all centralities.

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Li Yan, Jean-Yves Ollitrault, Arthur M. Poskanzer. 2014-09-03. Eccentricity distributions in nucleus-nucleus collisions. https://doi.org/10.1103/physrevc.90.024903

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