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arXiv · nucl-ex/0310029

Azimuthal anisotropy at RHIC: the first and fourth harmonics

STAR collaboration·J. Adams
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Abstract

We report the first observations of the first harmonic (directed flow, v_1), and the fourth harmonic (v_4), in the azimuthal distribution of particles with respect to the reaction plane in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). Both measurements were done taking advantage of the large elliptic flow (v_2) generated at RHIC. From the correlation of v_2 with v_1 it is determined that v_2 is positive, or {\it in-plane}. The integrated v_4 is about a factor of 10 smaller than v_2. For the sixth (v_6) and eighth (v_8) harmonics upper limits on the magnitudes are reported.

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STAR collaboration, J. Adams. 2004-01-22. Azimuthal anisotropy at RHIC: the first and fourth harmonics. https://doi.org/10.1103/physrevlett.92.062301

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