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arXiv · 1511.03896

Linear and cubic response to the initial eccentricity in heavy-ion collisions

Jacquelyn Noronha-Hostler·Li Yan·Fernando G. Gardim·Jean-Yves Ollitrault
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Abstract

We study the relation between elliptic flow, $v_2$ and the initial eccentricity, $\varepsilon_2$, in heavy-ion collisions, using hydrodynamic simulations. Significant deviations from linear eccentricity scaling are seen in more peripheral collisions. We identify the mechanism responsible for these deviations as a cubic response, which we argue is a generic property of the hydrodynamic response to the initial density profile. The cubic response increases elliptic flow fluctuations, thereby improving agreement of initial condition models with experimental data.

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Jacquelyn Noronha-Hostler, Li Yan, Fernando G. Gardim, Jean-Yves Ollitrault. 2016-01-19. Linear and cubic response to the initial eccentricity in heavy-ion collisions. https://doi.org/10.1103/physrevc.93.014909

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