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arXiv · 0907.0168

Scaling patterns of the suppression of $π^0$ yields in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV: links to the transport properties of the QGP

Roy A. Lacey·N. N. Ajitanand·J. M. Alexander·X. Gong·J. Jia·A. Taranenko·Rui Wei
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Abstract

Suppression measurements for neutral pions ($π^0$) are used to investigate the predicted path length ($L$) and transverse momentum ($p_T$) dependent jet quenching patterns of the hot QCD medium produced in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV. The observed scaling patterns show the predicted trends for jet-medium interactions dominated by radiative energy loss. They also allow simple estimates of the transport coefficient $\hat{q}$ and the ratio of viscosity to entropy density $η/s$. These estimates indicate that the short mean free path ($λ$) in the QCD medium leading to hydrodynamic-like flow with a small value of $η/s$, is also responsible for the strong suppression observed.

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Roy A. Lacey, N. N. Ajitanand, J. M. Alexander, X. Gong, J. Jia, A. Taranenko, Rui Wei. 2009-10-20. Scaling patterns of the suppression of $π^0$ yields in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV: links to the transport properties of the QGP. https://doi.org/10.1103/physrevc.80.051901

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