Speaker
Description
Reanalysis of the relatively old data collected by the CERES/NA45 experiment at the CERN SPS in 0–30% central PbAu collisions at $\sqrt{s_{NN}}$ = 17.3 GeV has been performed. For the first time, the measurement of the $v^{1/3}_{3}/v^{1/2}_{2}$ ratio reveals, independently of the hydrodynamic models, hydrodynamic behavior of the formed system. Recently, the CMS data have revealed long-range correlations within high-multiplicity jets in proton-proton (pp) collisions at $\sqrt{s}$ = 13 TeV, suggesting collective behavior in systems much smaller than those typical of heavy ion collisions. The Q-cumulant analysis, performed using data from a single image of the expanding ultra cold gas, shows a proper cumulant ordering among the $v_{2}$ harmonics $v_{2}\{2k\} \gtrsim v_{2}\{2(k+1)\}$ up to high order $2k$. That splitting enabled calculation of the corresponding hydro probes. Additionally, the Q-cumulant analysis has been performed in a single AuAu collision at $\sqrt{s_{NN}}$ = 200.0~GeV. Cumulant splitting in a single event has been observed for the first time.
