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arXiv · 1801.01277

A remark on the sign change of the four-particle azimuthal cumulant in small systems

Adam Bzdak·Guo-Liang Ma
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Abstract

The azimuthal cumulants, $c_2\{2\}$ and $c_2\{4\}$, originating from the global conservation of transverse momentum in the presence of hydro-like elliptic flow are calculated. We observe the sign change of $c_2\{4\}$ for small number of produced particles. This is in a qualitative agreement with the recent ATLAS measurement of multi-particle azimuthal correlations with the subevent cumulant method.

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Adam Bzdak, Guo-Liang Ma. 2018-01-04. A remark on the sign change of the four-particle azimuthal cumulant in small systems. https://doi.org/10.1016/j.physletb.2018.03.068

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