Detailed study of high-p{sub T} neutral pion suppression and azimuthal anisotropy in Au+Au collisions at {radical}(s{sub NN})=200 GeV

Measurements of neutral pion ({pi}{sup 0}) production at midrapidity in {radical}(s{sub NN})=200 GeV Au+Au collisions as a function of transverse momentum, p{sub T}, collision centrality, and angle with respect to reaction plane are presented. The data represent the final {pi}{sup 0} results from the PHENIX experiment for the first RHIC Au+Au run at design center-of-mass energy. They include additional data obtained using the PHENIX Level-2 trigger with more than a factor of 3 increase in statistics over previously published results for p{sub T}>6 GeV/c. We evaluate the suppression in the yield of high-p{sub T} {pi}{sup 0}'s relative to pointlike scaling expectations using the nuclear modification factor R{sub AA}. We present the p{sub T} dependence of R{sub AA} for nine bins in collision centrality. We separately integrate R{sub AA} over larger p{sub T} bins to show more precisely the centrality dependence of the high-p{sub T} suppression. We then evaluate the dependence of the high-p{sub T} suppression on the emission angle {delta}{phi} of the pions with respect to event reaction plane for seven bins in collision centrality. We show that the yields of high-p{sub T} {pi}{sup 0}'s vary strongly with {delta}{phi}, consistent with prior measurements 1,2. We show that this variation persists more » in the most peripheral bin accessible in this analysis. For the peripheral bins we observe no suppression for neutral pions produced aligned with the reaction plane, whereas the yield of {pi}{sup 0}'s produced perpendicular to the reaction plane is suppressed by a factor of {approx}2. We analyze the combined centrality and {delta}{phi} dependence of the {pi}{sup 0} suppression in different p{sub T} bins using different possible descriptions of parton energy loss dependence on jet path-length averages to determine whether a single geometric picture can explain the observed suppression pattern. « less