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arXiv · 1903.06366

Relating eccentricity fluctuations to density fluctuations in heavy-ion collisions

Rajeev S. Bhalerao·Giuliano Giacalone·Pablo Guerrero-Rodríguez·Matthew Luzum·Cyrille Marquet·Jean-Yves Ollitrault
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Abstract

The magnitude of anisotropic flow in a nucleus-nucleus collision is determined by the energy density field, $\rho(x,y,z)$, created right after the collision occurs. Specifically, elliptic flow, $v_2$, and triangular flow, $v_3$, are proportional to the anisotropy coefficients $\varepsilon_2$ and $\varepsilon_3$, which are functionals of $\rho$. We express the mean and the variance of $\varepsilon_2$ and $\varepsilon_3$ as a function of the 1- and 2-point functions of $\rho$. These results generalize results obtained previously, that were valid only for central collisions, or only for identical point-like sources. We apply them to the color glass condensate effective theory, using the recently derived expression of the 2-point function.

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Rajeev S. Bhalerao, Giuliano Giacalone, Pablo Guerrero-Rodríguez, Matthew Luzum, Cyrille Marquet, Jean-Yves Ollitrault. 2019-03-15. Relating eccentricity fluctuations to density fluctuations in heavy-ion collisions. https://doi.org/10.5506/aphyspolb.50.1165

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