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Title: Neutral pion production in Au+Au collisions at {radical}{ovr s}{sub NN} = 200 GeV.

Journal Article · · Phys. Rev. C

The results of midrapidity (0 < y < 0.8) neutral pion spectra over an extended transverse momentum range (1 < p{sub T} < 12 GeV/c) in {radical}{ovr s}{sub 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 or by the Time Projection Chamber via tracking of conversion electron-positron pairs. Our measurements are compared to previously published {pi}{sup {+-}} and {pi}{sup 0} results. The nuclear modification factors R{sub CP} and R{sub AA} of {pi}{sup 0} are also presented as a function of p{sub T}. In the most central Au+Au collisions, the binary collision scaled {pi}{sup 0} yield at high p{sub 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 the Relativistic Heavy Ion Collider.

Research Organization:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC); National Science Foundation (NSF); Sloan Foundation; EPSRC United Kingdom
DOE Contract Number:
DE-AC02-06CH11357
OSTI ID:
988140
Report Number(s):
ANL-HEP-PR-10-28; TRN: US1006616
Journal Information:
Phys. Rev. C, Vol. 80, Issue Oct. 2009
Country of Publication:
United States
Language:
ENGLISH