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Title: Measurement of flow harmonics with multi-particle cumulants in Pb+Pb collisions at √s NN = 2.76  TeV with the ATLAS detector

ATLAS measurements of the azimuthal anisotropy in lead–lead collisions at √s NN = 2.76 TeV are shown using a dataset of approximately 7 μb –1 collected at the LHC in 2010. The measurements are performed for charged particles with transverse momenta 0.5 < p T < 20 GeV and in the pseudorapidity range |η| < 2.5. The anisotropy is characterized by the Fourier coefficients, v n, of the charged-particle azimuthal angle distribution for n = 2–4. The Fourier coefficients are evaluated using multi-particle cumulants calculated with the generating function method. Results on the transverse momentum, pseudorapidity and centrality dependence of the v n coefficients are presented. The elliptic flow, v 2, is obtained from the two-, four-, six- and eight-particle cumulants while higher-order coefficients, v 3 and v 4, are determined with two- and four-particle cumulants. Flow harmonics v n measured with four-particle cumulants are significantly reduced compared to the measurement involving two-particle cumulants. A comparison to vn measurements obtained using different analysis methods and previously reported by the LHC experiments is also shown. Results of measurements of flow fluctuations evaluated with multi-particle cumulants are shown as a function of transverse momentum and the collision centrality. As a result, modelsmore » of the initial spatial geometry and its fluctuations fail to describe the flow fluctuations measurements.« less
Authors:
 [1]
  1. Aix-Marseille Univ. and CNRS/IN2P3, Marseille (France). et al.
Publication Date:
Grant/Contract Number:
AC02-06CH11357; AC02-05CH11231; SC0012704; AC03-76SF00515
Type:
Accepted Manuscript
Journal Name:
European Physical Journal. C, Particles and Fields
Additional Journal Information:
Journal Volume: 74; Journal Issue: 11; Journal ID: ISSN 1434-6044
Publisher:
Springer
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Contributing Orgs:
ATLAS Collaboration
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS
OSTI Identifier:
1407260
Alternate Identifier(s):
OSTI ID: 1225373; OSTI ID: 1225711