NEW RESULTS ON COLLECTIVITY WITH ATLAS

The collective phenomena are observed not only in heavy ion collisions, but also in the proton-nucleus and in high-multiplicity pp collisions. The latest results from this area obtained in ATLAS are presented. In p+Pb collisions the source of particles is measured using the HBT method. The analysis of p+Pb data collected in the end of 2016 provides information on the elliptic flow of charged hadrons and muons. Low multiplicity events from pp, p+Pb and peripheral Pb+Pb collisions are studied with the cumulant methods. A deeper understanding of Pb+Pb collisions is provided by the analysis of longitudinal fluctuations of the collective flow parameters.