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Particle Number Fluctuations in High Energy Nucleus-Nucleus Collisions from Microscopic Transport Approaches

V. P. Konchakovski·S. Haussler·M. I. Gorenstein·E. L. Bratkovskaya·M. Bleicher·H. Stoecker
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Abstract

Event-by-event multiplicity fluctuations in nucleus-nucleus collisions are studied within the HSD and UrQMD transport models. The scaled variances of negative, positive, and all charged hadrons in Pb+Pb at 158 AGeV are analyzed in comparison to the data from the NA49 Collaboration. We find a dominant role of the fluctuations in the nucleon participant number for the final hadron multiplicity fluctuations. This fact can be used to check different scenarios of nucleus-nucleus collisions by measuring the final multiplicity fluctuations as a function of collision centrality. The analysis reveals surprising effects in the recent NA49 data which indicate a rather strong mixing of the projectile and target hadron production sources even in peripheral collisions.

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V. P. Konchakovski, S. Haussler, M. I. Gorenstein, E. L. Bratkovskaya, M. Bleicher, H. Stoecker. 2006-02-06. Particle Number Fluctuations in High Energy Nucleus-Nucleus Collisions from Microscopic Transport Approaches. https://doi.org/10.1103/physrevc.73.034902

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