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arXiv · 0812.3967

Forward-backward correlations in nucleus-nucleus collisions: baseline contributions from geometrical fluctuations

V. P. Konchakovski·M. Hauer·G Torrieri·M. I. Gorenstein·E. L. Bratkovskaya
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Abstract

We discuss the effects of initial collision geometry and centrality bin definition on correlation and fluctuation observables in nucleus-nucleus collisions. We focus on the forward-backward correlation coefficient recently measured by the STAR Collaboration in Au+Au collisions at RHIC. Our study is carried out within two models: the Glauber Monte Carlo code with a `toy' wounded nucleon model and the hadron-string dynamics (HSD) transport approach. We show that strong correlations can arise due to averaging over events in one centrality bin. We, furthermore, argue that a study of the dependence of correlations on the centrality bin definition as well as the bin size may distinguish between these `trivial' correlations and correlations arising from `new physics'.

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V. P. Konchakovski, M. Hauer, G Torrieri, M. I. Gorenstein, E. L. Bratkovskaya. 2008-12-25. Forward-backward correlations in nucleus-nucleus collisions: baseline contributions from geometrical fluctuations. https://doi.org/10.1103/physrevc.79.034910

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