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High $p_{T}$ Inclusive Charged Hadron Spectra from Au+Au Collisions at $sqrt{s_{NN}}$ = 200 GeV

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 نشر من قبل Jennifer L. Klay
 تاريخ النشر 2002
  مجال البحث
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 تأليف Jennifer L. Klay




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The STAR Collaboration presents new measurements of inclusive charged hadron distributions for $p_{T} <$ 12 GeV/c from Au+Au collisions at $sqrt{s_{NN}}$ = 200 GeV. Charged hadron suppression at high $p_{T}$ is similar in shape and magnitude at all centralities to that observed previously at $sqrt{s_{NN}}$ = 130 GeV for $p_{T} <$ 6 GeV/c. The ratio of spectra from central and peripheral Au+Au collisions shows that hadron suppression is approximately constant within 6 $< p_{T} <$ 12 GeV/c. The ratios of charged hadron spectra at the two beam energies show a 15-20% increase in yield at low $p_{T}$. At high $p_{T}$, the ratios show a larger increase that agrees well with pQCD calculations of the $sqrt{s_{NN}}$ dependence of particle production in Au+Au collisions.



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