Third Harmonic Flow of Charged Particles in Au+Au Collisions at sqrtsNN = 200 GeV

TL;DR

This paper measures the third harmonic flow coefficient v_3 of charged particles in gold-gold collisions at 200 GeV, revealing pseudorapidity gap dependence and comparing results with models and other experiments.

Contribution

It provides the first detailed measurement of triangular flow v_3 in Au+Au collisions at 200 GeV using multiple analysis methods and pseudorapidity gap techniques.

Findings

Triangular flow v_3 varies with transverse momentum and centrality.

Pseudorapidity gap significantly affects v_3 measurements.

Results are consistent with some model predictions and differ from others.

Abstract

We report measurements of the third harmonic coefficient of the azimuthal anisotropy, v_3, known as triangular flow. The analysis is for charged particles in Au+Au collisions at sqrtsNN = 200 GeV, based on data from the STAR experiment at the Relativistic Heavy Ion Collider. Two-particle correlations as a function of their pseudorapidity separation are fit with narrow and wide Gaussians. Measurements of triangular flow are extracted from the wide Gaussian, from two-particle cumulants with a pseudorapidity gap, and also from event plane analysis methods with a large pseudorapidity gap between the particles and the event plane. These results are reported as a function of transverse momentum and centrality. A large dependence on the pseudorapidity gap is found. Results are compared with other experiments and model calculations.