Statistical properties of non-flow correlations in pp and heavy-ion collisions at RHIC energies

Abstract

In this work, we have studied the two-particle cumulant in pp, d-Au, and Au-Au collisions. The two-particle cumulant was treated as an event-by-event distribution, and its skewness and kurtosis were analyzed. The non-flow correlations, like jets and decays, constantly produced a skewed distribution, regardless of the model used. On the contrary, HYDJET++ produced a smooth Gaussian distribution at higher $η$ windows in fixed impact parameter collisions. The skewness increased consistently for higher $η$ windows in all non-QGP models like PYTHIA, PHOJET, QGSJET, and DPMJET. The kurtosis of the distribution also increased with $η$ windows in non-QGP models. The skewness and kurtosis of the distributions produced by HYDJET++ decreased with $Δη$ and eventually reached zero at higher $Δη$.

Figures (7)

• Figure 1: The two-particle cumulant $c_2$ distribution of charged hadrons with different models in pp collisions at 200 GeV.
• Figure 2: The two-particle cumulant $c_2$ distribution of charged hadrons in d-Au collisions and pp collisions with a $\eta$-gap.
• Figure 3: The two-particle cumulant $c_2$ distribution of charged hadrons in Au-Au collisions at 200 GeV with different configurations of HYDJET++.
• Figure 4: The two-particle cumulant $c_2$ of charged hadrons in minimum bias Au-Au collisions at 200 GeV using HYDJET++ (jets only) and Angantyr.
• Figure 5: The average two-particle cumulant $<c_2>$ of charged hadrons and the skewness of $c_2$ distribution as a function of impact parameter in Au-Au collisions using PYTHIA8/Angantyr.