Elliptic azimuthal anisotropy of charged hadrons and neutral pions in PbPb collisions at 2.76 TeV with CMS

Eric Appelt

doi:10.1016/j.nuclphysa.2013.02.059

Abstract

Abstract The elliptic flow anisotropies of charged particles and neutral pions ( π 0 s ) have been measured by the CMS collaboration for PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV. The second Fourier components of the anisotropic azimuthal distribution are obtained using an event-plane technique for π 0 s and four different analysis techniques for charged particles: event plane, two- and four-particle cumulants, and Lee-Yang Zeros. These techniques have different sensitivities to non-flow and flow fluctuation effects and their comparison helps disentangle hydrodynamic flow, initial state fluctuations and non-flow correlations. A comparison of the CMS measurements of v 2 ( p T ) from π 0 mesons and inclusive charged particles indicates a particle-species dependence in the azimuthal anisotropy at the LHC.

Highlights

The elliptic flow anisotropies of charged particles and neutral pions (π0s) have been measured by the CMS collaboration for PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV
The azimuthal anisotropy of charged hadrons and identified particles produced in PbPb collisions are typically characterized by the coefficients of Fourier harmonics in an azimuthal distribution (φ) of the charged particle yield, dN/dφ ∝ 1 +
The results presented particles produced in PbPb here include collisions at d√estaNNile=d measurements 2.76 TeV in a broad kinematic range of |η| < 2.4, and 0.3 < pT < 20, in the centrality range of 0-80% of the total inelastic PbPb cross-section

Summary

Introduction

Elliptic azimuthal anisotropy of charged hadrons and neutral pions in PbPb collisions at 2.76 TeV with CMS The elliptic flow anisotropies of charged particles and neutral pions (π0s) have been measured by the CMS collaboration for PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV.

Results

Conclusion