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Multiplicity Fluctuations in Proton-Proton and Nucleus-Nucleus Collisions

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

We study the scaled variances of multiplicity fluctuations in nucleus-nucleus collisions at SPS and RHIC energies within the HSD transport model. The HSD results are compared with proton-proton data and with predictions of the hadron-resonance gas statistical model. We find that the HSD scaled variances $ω_i$ for negatively, positively, and all charged hadrons in central nucleus-nucleus collisions remain close to the $ω_i$ values in proton-proton collisions and increase with collision energy as the corresponding multiplicities per participating nucleon. The statistical model predicts very different behavior of $ω_i$. However, a comparison with preliminary NA49 data for the most central Pb+Pb collisions at SPS energies does not permit to distinguish the HSD and statistical model results. New measurements of the multiplicity fluctuations in nucleus-nucleus collisions in a wide energy region with large acceptance are needed to allow for a proper determination of the underlying dynamics.

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V. P. Konchakovski, M. I. Gorenstein, E. L. Bratkovskaya. 2007-05-24. Multiplicity Fluctuations in Proton-Proton and Nucleus-Nucleus Collisions. https://doi.org/10.1016/j.physletb.2007.06.032

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