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Measurement of D* Mesons in Jets from p+p Collisions at sqrt{s} = 200 GeV

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 نشر من قبل Xin Dong
 تاريخ النشر 2009
  مجال البحث
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We report the measurement of charged $D^*$ mesons in inclusive jets produced in proton-proton collisions at a center of mass energy $sqrt{s}$ = 200 GeV with the STAR experiment at RHIC. For $D^{*}$ mesons with fractional momenta $0.2 < z < 0.5$ in inclusive jets with 11.5 GeV mean transverse energy, the production rate is found to be $N(D^{*+}+D^{*-})/N(mathrm{jet}) = 0.015 pm 0.008 (mathrm{stat}) pm 0.007 (mathrm{sys})$. This rate is consistent with perturbative QCD evaluation of gluon splitting into a pair of charm quarks and subsequent hadronization.

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