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تسجيل مستخدم جديدGround and excited charmonium state production in p+p collisions at sqrt(s)=200 GeV
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We report on charmonium measurements [J/psi(1S), psi(2S), and chi_c(1P)] in p+p collisions at sqrt(s)=200 GeV. We find that the fraction of J/psi coming from the feed-down decay of psi and chi_c in the midrapidity region ($|eta|<0.35$) is 9.6+/-2.4% and 32+/-9%, respectively. We also report new, higher statistics p_T and rapidity dependencies of the J/psi yield via dielectron decay in the same midrapidity range and at forward rapidity (1.2<|eta|<2.4) via dimuon decay. These results are compared with measurements from other experiments and discussed in the context of current charmonium production models.
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