Neutral pion production inAu+Aucollisions atsNN=200GeV

B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, B. D. Anderson, D. Arkhipkin, G. S. Averichev, J. Balewski, O. Barannikova, L. S. Barnby, J. Baudot, S. Baumgart (+370 others)
2009 Physical Review C  
The results of mid-rapidity (0 < y < 0.8) neutral pion spectra over an extended transverse momentum range (1 < p_T < 12 GeV/c) in √(s_NN) = 200 GeV Au+Au collisions, measured by the STAR experiment, are presented. The neutral pions are reconstructed from photons measured either by the STAR Barrel Electro-Magnetic Calorimeter (BEMC) or by the Time Projection Chamber (TPC) via tracking of conversion electron-positron pairs. Our measurements are compared to previously published π^± and π^0
more » ... The nuclear modification factors R_CP and R_AA of π^0 are also presented as a function of p_T . In the most central Au+Au collisions, the binary collision scaled π^0 yield at high p_T is suppressed by a factor of about 5 compared to the expectation from the yield of p+p collisions. Such a large suppression is in agreement with previous observations for light quark mesons and is consistent with the scenario that partons suffer considerable energy loss in the dense medium formed in central nucleus-nucleus collisions at RHIC.
doi:10.1103/physrevc.80.044905 fatcat:zth2qwwonvc6hieatnimz422rm