CERN Accelerating science

ATLAS Slides
Report number ATL-PHYS-SLIDE-2018-261
Title Measurement of
 the azimuthal anisotropy of charged particles 
in 5.02 TeV Pb+Pb and 5.44 TeV Xe+Xe collisions 
with ATLAS
Author(s) Bold, Tomasz (AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Krakow)
Corporate author(s) The ATLAS collaboration
Collaboration ATLAS Collaboration
Submitted to The 27th International Conference on Ultrarelativistic Nucleus-Nucleus Collisions, Venice, Italy, 13 - 19 May 2018
Submitted by tomasz.bold@gmail.com on 21 May 2018
Subject category Particle Physics - Experiment
Accelerator/Facility, Experiment CERN LHC ; ATLAS
Free keywords flow ; flow correlations ; Xe+Xe collisions ; HEAVYIONS
Abstract The experimental data collected by the ATLAS experiment during the 2015 Pb+Pb and 2017 Xe+Xe LHC runs offer new opportunities to study charged particle azimuthal anisotropy. The high-statistics Pb+Pb sample allows for a detailed study of the azimuthal anisotropy of produced particles. This should improve the understanding of initial conditions of nuclear collisions, hydrodynamical behavior of quark-gluon plasma and parton energy loss. New ATLAS measurements of differential and global Fourier harmonics of charged particles (vn) in 5.02 TeV Pb+Pb and 5.44 TeV Xe+Xe collisions in a wide range of transverse momenta, pseudorapidity (|η|<2.5) and collision centrality are presented. The higher order harmonics, sensitive to fluctuations in the initial state, are measured up to n=7 using the two-particle correlation, cumulant and scalar product methods. The dynamic properties of QGP are studied using a recently-proposed modified Pearson's correlation coefficient, ρ(v2n,pT), between the eventwise mean transverse momentum and the magnitude of the flow vector in 5.02 TeV Pb+Pb and p+Pb collisions. Several important observations are made. The elliptic and triangular flow harmonics show an interesting universal pT-scaling. A linear correlation between the v2 and v3 coefficients at low and high pT ranges is observed and quantified. The Pearson's correlation coefficient ρ(v22) is found to be negative in peripheral and positive in central Pb+Pb collisions. The value of ρ(v23) is found to be much smaller than ρ(v22) and to have similar centrality behavior as ρ(v22).



 Record created 2018-05-21, last modified 2018-05-21


  • Send to ScienceWise.info