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arXiv · 0905.4368

Is the quark gluon plasma produced in RHIC collisions strongly coupled?

Roy A. Lacey·Arkadij Taranenko·Rui Wei
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Abstract

Recent hexadecapole (v4) and elliptic (v2) flow measurements are used to constrain estimates for the degree of local equilibrium, mean free path $λ$, and the viscosity to entropy density ratio (eta/s) of the plasma produced in Au+Au collisions at RootS = 200 GeV. The eccentricity-scaled flow coefficients v2/e2 and v4/e4 indicate that the plasma achieves a degree of local equilibrium within 5 - 10% of the value expected for a fluid with eta/s equal to the conjectured lower bound of 1/4pi. Estimates for $λ$ and eta/s as a function of collision centrality and particle transverse momentum pT, points to transverse expansion dynamics compatible with a strongly coupled low viscosity plasma.

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Roy A. Lacey, Arkadij Taranenko, Rui Wei. 2009-05-29. Is the quark gluon plasma produced in RHIC collisions strongly coupled?. https://arxiv.org/abs/0905.4368

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