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Large Observed $v_2$ as a Signature for Deconfinement

W. A. Horowitz
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Abstract

We present a new plot for representing RAA data that emphasizes the strong correlation between high-pt suppression and its elliptic anisotropy. We demonstrate that existing models cannot reproduce the centrality dependence of this correlation. Modification of a geometric energy loss model to include thermal absorption and stimulated emission can match the trend of the data, but requires dN/dy values inconsistent with the observed multiplicity. By including a small, outward-normal directed surface impulse opposing energy loss, $Δpt \hat{n}$, one can account for the centrality dependence of the observed Au+Au elliptic quench pattern. We also present predictions for Cu+Cu reactions.

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W. A. Horowitz. 2006-02-01. Large Observed $v_2$ as a Signature for Deconfinement. https://doi.org/10.1556/aph.27.2006.2-3.10

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