Particle-Type Dependence of Azimuthal Anisotropy and Nuclear Modification of Particle Production in Au + Au Collisions at √S_NN= 200 GeV

We present STAR measurements of the azimuthal anisotropy parameter ν₂ and the binary-collision scaled centrality ratio R_CP for kaons and lambdas (Λ + Λ) at midrapidity in Au + Au collisions at √s_NN = 200 GeV. In combination, the ν₂ and R_CP particle-type dependencies contradict expectations from partonic energy loss followed by standard fragmentation in vacuum We establish p_T ≈ 5 GeV/c as the value where the centrality dependent baryon enhancement ends. The K0 and Λ + Λ¯ ν₂ values are consistent with expectations of constituent-quark-number scaling from models of hadron formation by parton coalescence or recombination.