Identified Baryon and Meson Distributions at Large Transverse Momenta from Au Plus Au Collisions at Root(S)(Nn)=200 Gev10/13/2006
Transverse momentum spectra of pi(+/-), p, and (p) over bar p up to 12 GeV/c at midrapidity in centrality selected Au + Au collisions at root s(NN) = 200 GeV are presented. In central Au + Au collisions, both pi(+/-) and p((p) over bar) show significant suppression with respect to binary scaling at p(T) greater than or similar to 4 GeV/c. Protons and antiprotons are less suppressed than pi(+/-), in the range 1.5 less than or similar to p(T) less than or similar to 6 GeV/c. The pi(-)/pi(+) and (p) over bar /p ratios show at most a weak pT dependence and no significant centrality dependence. The p/pi ratios in central Au + Au collisions approach the values in p + p and d + Au collisions at p(T) greater than or similar to 5 GeV/c. The results at high p(T) indicate that the partonic sources of pi(+/-), p, and (p) over bar have similar energy loss when traversing the nuclear medium.