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arXiv · 1711.07789

Event-by-event fluctuations in p+p and central A+A collisions within relativistic transport models

Anton Motornenko·Katarzyna Grebieszkow·Elena Bratkovskaya·Mark I. Gorenstein·Marcus Bleicher·Klaus Werner
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Abstract

Event-by-event multiplicity fluctuations in nucleus-nucleus collisions are studied within the relativistic transport models: EPOS, PHSD, and UrQMD. As measures of particle number fluctuations we consider the scaled variances $ω[X]$ for positive, negative, and all charged hadrons, and the strongly intensive quantities $Δ[K^+,π^+],$ $Σ[K^+,π^+]$ for $K^+$ and $π^+$ yields. At the SPS energy range the fluctuation measures are calculated for proton-proton, Ar+Sc, and Pb+Pb collisions. Comparison with recent NA61/SHINE and older NA49 measurements of the multiplicity fluctuations is done. A validity of the model of independent sources, a role of the experimental acceptance, and the centrality selection procedure are studied.Event-by-event multiplicity fluctuations in nucleus-nucleus collisions are studied within the relativistic transport models: EPOS, PHSD, and UrQMD. As measures of particle number fluctuations we consider the scaled variances $ω[X]$ for positive, negative, and all charged hadrons, and the strongly intensive quantities $Δ[K^+,π^+],$ $Σ[K^+,π^+]$ for $K^+$ and $π^+$ yields. At the SPS energy range the fluctuation measures are calculated for proton-proton, Ar+Sc, and Pb+Pb collisions. Comparison with recent NA61/SHINE and older NA49 measurements of the multiplicity fluctuations is done. A validity of the model of independent sources, a role of the experimental acceptance, and the centrality selection procedure are studied.

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Anton Motornenko, Katarzyna Grebieszkow, Elena Bratkovskaya, Mark I. Gorenstein, Marcus Bleicher, Klaus Werner. 2018-10-02. Event-by-event fluctuations in p+p and central A+A collisions within relativistic transport models. https://doi.org/10.1088/1361-6471%2Faae149

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