Measurement of long-range two- and multi-particle correlations by ALICE

Abstract

Measurements of long-range particle correlations provide critical insights into the properties of the strongly coupled matter created in heavy-ion collisions and even in small collision systems, such as pp and p–Pb collisions. New results on long-range two-particle correlations for different multiplicity classes and ν2(η) in p–Pb collisions at 5.02 TeV are presented. These measurements utilize the Forward Multiplicity Detector (FMD), which allows for unprecedented Δη ranges to be explored (up to |Δη| ∼ 8) and to extract the pseudo-rapidity dependence of flow with wide pseudo-rapidity range (−3.4 <η < 5). The first measurement of the pseudo-rapidity dependence of two- and multi-particle cumulants in Pb–Pb collisions at 5.02 TeV is also presented. With the future hydrodynamic calculations, the presented results will provide key constraints on the temperature dependence of the shear viscosity over entropy density ratio. In addition, by comparing to AMPT model calculations, the ALICE data provide precise information on the 3D evolution of the hot and dense matter created in heavy-ion collisions and small collision systems.