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Eccentricity fluctuations and elliptic flow at RHIC

Rajeev S. Bhalerao·Jean-Yves Ollitrault
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Abstract

Fluctuations in nucleon positions can affect the spatial eccentricity of the overlap zone in nucleus-nucleus collisions. We show that elliptic flow should be scaled by different eccentricities depending on which method is used for the flow analysis. These eccentricities are estimated semi-analytically. When $v_2$ is analyzed from 4-particle cumulants, or using the event plane from directed flow in a zero-degree calorimeter, the result is shown to be insensitive to eccentricity fluctuations.

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Rajeev S. Bhalerao, Jean-Yves Ollitrault. 2006-08-17. Eccentricity fluctuations and elliptic flow at RHIC. https://doi.org/10.1016/j.physletb.2006.08.055

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