The Modification of high-$p_{T}$ hadro-chemistry in Au+Au collisions relative to p+p

Abstract

We present high transverse momentum, $p_{T}$, pion ($\pi$), proton ($p$), kaon ($K$), and rho ($\rho$) spectra measured with the STAR experiment from p+p and Au+Au collisions with \sNN{200}. We find the $K/\pi$ ratio to be enhanced in Au+Au \sNN{200} collisions relative to p+p \sNN{200} collisions at $p_{T} > 5$ GeV/c. The enhancement persists until $p_{T} \sim 12$ GeV/c for central Au+Au 200 GeV collisions. We also show the nuclear modification factor, $R_{AA}$, measured at the same center of mass energy, and find $R_{AA}(K)$ and $R_{AA}(p)$ to be higher than $R_{AA}(\pi)$ at $p_T > 5$ GeV/c. Implications for medium induced modifications of jet chemistry is discussed.