The invariant yields d²N/(2πpTdpTdy) of π^±, K^±, K⁰_S, ρ⁰, p, and pbar from non-singly diffractive p+pcollisions (σ_NSD=30.0±3.5 mb), those of K+p(pbar), K⁰_S, and ρ⁰, in central Au+Au collisions, and NLO calculations with AKK and DSS FFs. The uncertainty of yields due to the scale dependence as evaluated in DSS calculations is about a factor of 2. Bars and boxes (bands) represent statistical and systematic uncertainties, respectively.

Yield ratios π^-/π⁺, pbar/p, K^-/K⁺, p/π⁺, pbar/π^-, and K^±, K⁰_S/π^± versus p_T in p+p collisions, and nominal NLO calculations with AKK and DSS FFs without theoretical uncertainties. The open squares in panels (d) and (e) are the p/π⁺ and pbar/π^- ratios in central Au+Au collisions with updated uncertainties at high p_T, and all other data points are from p+p collisions. Bars and boxes (bands) represent statistical and systematic uncertainties, respectively.

(a) R_AA of K^±+p(pbar), K⁰_S, ρ⁰, and π^± in central Au+Au collisions as a function of p_T. The curves are the calculations for K⁰_S R_AAwith and without jet conversion in medium. Bars and boxes (bands) represent statistical and systematic uncertainties, respectively. The height of the band at unity represents the normalization uncertainty. (b) The ratios of R_AA[K^±+p(pbar), ρ⁰] to R_AA(π^±) and R_AA(K^-+pbar) to R_AA(K⁺+p). The boxes and shaded bands represent the systematic uncertainties for R_AA(ρ⁰)/R_AA(π^±) and R_AA[K^±+p(pbar)]/R_AA(π^±), respectively. The systematic uncertainties for R_AA(K^-+pbar)/R_AA(K⁺+p) are 2--12% and left off for clarity.

We report identified particle pT spectra at mid-rapidity up to 15 GeV/c from p+p and Au+Au collisions at √s_NN = 200 GeV. The NLO pQCD models describe the π^± spectra but fail to reproduce the K and p(pbar) spectra at high p_T. The measured anti-particle to particle ratios are observed to decrease with increasing pT. This reflects differences in scattering contributions to the production of particles and anti-particles at RHIC. At pT≥8 GeV/c, a common suppression pattern is observed for different particle species. Incorporating our p+p data in generating the flavor separated FFs in the same kinematic range will provide new inputs and insights into the mechanisms of jet quenching in heavy ion collisions.