Higher Harmonic Anisotropic Flow Measurements of Charged Particles in Pb-Pb Collisions at √sNN = 2.76 TeV

ALICE Collaboration

Midori J.

Obayashi H.

Sakaguchi H.

Shigaki Kenta

Sugitate Toru

Torii H.

Physical Review Letters

We report on the first measurement of the triangular v3, quadrangular v4, and pentagonal v5 charged particle flow in Pb-Pb collisions at √sNN = 2.76 TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow v2 and v3 have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.

Physics [ 420 ]

eng

American Physical Society

Copyright (c) 2011 CERN, for the ALICE Collaboration

This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

[ISSN] 0031-9007

[NCID] AA00773679

[DOI] 10.1103/PhysRevLett.107.032301