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arXiv · hep-ph/0202057

Charged particle fluctuations and microscopic models of nuclear collisions

Q. H. Zhang·V. Topor Pop·S. Jeon·C. Gale
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Abstract

We study the event-by-event fluctuations of the charged particles and compare the results of different Monte-Carlo Generators (MCG): VNIb, HIJING, HIJING/B${\bar B}$ and RQMD. We find that the $D$-measure can be used to distinguish between the different gluon populations that are present in the MCG models. On the other hand, the value of the $D$-measure shows high sensitivity to the rescattering effects in VNIb model, but lower sensitivity to the rescattering effects in RQMD model. We also find that the $D$-measures from AA are consistent with the $D$-measures from $pp$ for all generators except VNIb. Therefore, any deviation among the values of $D$-measure for different impact parameters and between $pp$ and $AA$ collisions may indicate that either the rescattering effects play a key role in the interactions or there is new physics in $AA$ collisions.

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Q. H. Zhang, V. Topor Pop, S. Jeon, C. Gale. 2002-05-28. Charged particle fluctuations and microscopic models of nuclear collisions. https://doi.org/10.1103/physrevc.66.014909

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