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Title: Identified hadron transverse momentum spectra in Au + Au collisions at {radical}{ovr S} {sub NN} = 62.4 GeV.

Journal Article · · Phys. Rev. C

Transverse momentum spectra of pions, kaons, protons, and antiprotons from Au+Au collisions at {radical}S{sub NN} = 62.4 GeV have been measured by the PHOBOS experiment at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The identification of particles relies on three different methods: low momentum particles stopping in the first detector layers; the specific energy loss (dE/dx) in the silicon spectrometer, and time-of-flight measurement. These methods cover the transverse momentum ranges 0.03-0.2, 0.2-1.0, and 0.5-3.0 GeV/c, respectively. Baryons are found to have substantially harder transverse momentum spectra than mesons. The p{sub T} region in which the proton to pion ratio reaches unity in central Au+Au collisions at {radical}S{sub NN} = 62.4 GeV fits into a smooth trend as a function of collision energy. At low transverse mass, the spectra of various species exhibit a significant deviation from transverse mass scaling. The observed particle yields at very low p{sub T} are comparable to extrapolations from higher p{sub T} for kaons, protons and antiprotons. By comparing our results to Au+Au collisions at {radical}S{sub NN} = 200 GeV, we conclude that the net proton yield at midrapidity is proportional to the number of participant nucleons in the collision.

Research Organization:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
DOE Contract Number:
DE-AC02-06CH11357
OSTI ID:
940694
Report Number(s):
ANL/PHY/JA-57744; PRVCAN; TRN: US0807186
Journal Information:
Phys. Rev. C, Vol. 75, Issue 2007; ISSN 0556-2813
Country of Publication:
United States
Language:
ENGLISH