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arXiv · 0810.5414

Centrality dependence of v2 in Au + Au at sqrt{s_NN} = 200 GeV

Hiroshi Masui
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Abstract

One of the most striking results is the large elliptic flow ($v_2$) at RHIC. Detailed mass and transverse momentum dependence of elliptic flow are well described by ideal hydrodynamic calculations for $p_{\mathrm{T}} < $ 1 GeV/c, and by parton coalescence/recombination picture for $p_{\mathrm{T}} = 2 - 6$ GeV/c. The systematic error on $v_2$ is dominated by so-called "non-flow effects", which is the correlation not originated from reaction plane. It is crucial to understand and reduce the systematic error from non-flow effects in order to understand the underlying collision dynamics. In this paper, we present the centrality dependence of $v_2$ with respect to the first harmonic event plane at ZDC-SMD ($v_2$\{ZDC-SMD\}) in Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. Large rapidity gap ($|Δη| > 6$) between midrapidity and the ZDC could enable us to minimize possible non-flow contributions. We compare the results of $v_2$\{ZDC-SMD\} with $v_2$\{BBC\}, which is measured by event plane determined at $|η| = 3.1 - 3.9$. Possible non-flow contributions in those results will be discussed.

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Hiroshi Masui. 2008-10-30. Centrality dependence of v2 in Au + Au at sqrt{s_NN} = 200 GeV. https://doi.org/10.1140/epjc%2Fs10052-009-1019-x

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