اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurements of $D^{0}$ and $D^{*}$ Production in $p$ + $p$ Collisions at $sqrt{s}$ = 200 GeV
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We report measurements of charmed-hadron ($D^{0}$, $D^{*}$) production cross sections at mid-rapidity in $p$ + $p$ collisions at a center-of-mass energy of 200 GeV by the STAR experiment. Charmed hadrons were reconstructed via the hadronic decays $D^{0}rightarrow K^{-}pi^{+}$, $D^{*+}rightarrow D^{0}pi^{+}rightarrow K^{-}pi^{+}pi^{+}$ and their charge conjugates, covering the $p_T$ range of 0.6$-$2.0 GeV/$c$ and 2.0$-$6.0 GeV/$c$ for $D^{0}$ and $D^{*+}$, respectively. From this analysis, the charm-pair production cross section at mid-rapidity is $dsigma/dy|_{y=0}^{cbar{c}}$ = 170 $pm$ 45 (stat.) $^{+38}_{-59}$ (sys.) $mu$b. The extracted charm-pair cross section is compared to perturbative QCD calculations. The transverse momentum differential cross section is found to be consistent with the upper bound of a Fixed-Order Next-to-Leading Logarithm calculation.
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