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arXiv · 1502.05572

Anisotropic parton escape is the dominant source of azimuthal anisotropy in transport models

Liang He·Terrence Edmonds·Zi-Wei Lin·Feng Liu·Denes Molnar·Fuqiang Wang
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Abstract

We trace the development of elliptic anisotropy ($v_2$) via parton-parton collision history in two transport models. The parton $v_2$ is studied as a function of the number of collisions of each parton in Au+Au and $d$+Au collisions at $\sqrt{s_{_{\rm NN}}}=200$ GeV. It is found that the majority of $v_2$ comes from the anisotropic escape probability of partons, with no fundamental difference at low and high transverse momenta. The contribution to $v_2$ from hydrodynamic-type collective flow is found to be small. Only when the parton-parton cross-section is set unrealistically large does this contribution start to take over. Our findings challenge the current paradigm emerged from hydrodynamic comparisons to anisotropy data.

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Liang He, Terrence Edmonds, Zi-Wei Lin, Feng Liu, Denes Molnar, Fuqiang Wang. 2015-02-19. Anisotropic parton escape is the dominant source of azimuthal anisotropy in transport models. https://doi.org/10.1016/j.physletb.2015.12.051

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