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arXiv · 1602.07089

Cumulants of multiplicity distributions in most-central heavy-ion collisions

Hao-jie Xu
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Abstract

I investigate the volume corrections on cumulants of total charge distributions and net proton distributions. The required volume information is generated by an optical Glauber model. I find that the corrected statistical expectations of multiplicity distributions mimic the negative binomial distributions at non-central collisions, and they tend to approach the Poisson ones at most-central collisions due to the "boundary effects," which suppress the volume corrections. However, net proton distributions and reference multiplicity distributions are sensitive to the external volume fluctuations at most-central collisions, which imply that one has to consider the details of volume distributions in event-by-event multiplicity fluctuation studies.

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Hao-jie Xu. 2016-11-08. Cumulants of multiplicity distributions in most-central heavy-ion collisions. https://doi.org/10.1103/physrevc.94.054903

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