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arXiv · 0906.3566

Elliptic flow of thermal photons at midrapidity in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV

Fu-Ming Liu·Tetsufumi Hirano·Klaus Werner·Yan Zhu
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Abstract

The elliptic flow $v_{2}$ of thermal photons at midrapidity in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV is predicted, based on three-dimensional ideal hydrodynamics. Because of the interplay between the asymmetry and the strength of the transverse flow, the thermal photon $v_{2}$ reaches a maximum at $\pt \sim $ 2GeV/$c$ and the $\pt$-integrated $v_{2}$ reaches a maximum at about 50% centrality. The $\pt$-integrated $v_{2}$ is very sensitive to the lower limit of the integral but not sensitive to the upper limit due to the rapid decrease in the spectrum of the transverse momentum.

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Fu-Ming Liu, Tetsufumi Hirano, Klaus Werner, Yan Zhu. 2009-09-17. Elliptic flow of thermal photons at midrapidity in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV. https://doi.org/10.1016/j.nuclphysa.2009.09.049

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