Large Observed $v_2$ as a Signature for Deconfinement

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, $\Delta pt \hat{n}$, one can account for the centrality dependence of the observed Au+Au elliptic quench pattern. We also present predictions for Cu+Cu reactions.