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arXiv · hep-ph/0605334

Recent PQCD calculations of heavy quark production

Abstract

We summarize the results of a recent study of heavy quark production and attenuation in cold nuclear matter. In p+p collisions, we investigate the relative contribution of partonic sub-processes to $D$ meson production and $D$ meson-triggered inclusive di-hadrons to lowest order in perturbative QCD. While gluon fusion dominates the creation of large angle $D\bar{D}$ pairs, charm on light parton scattering determines the yield of single inclusive $D$ mesons. The distinctly different non-perturbative fragmentation of $c$ quarks into $D$ mesons versus the fragmentation of quarks and gluons into light hadrons results in a strong transverse momentum dependence of anticharm content of the away-side charm-triggered jet. In p+A reactions, we calculate and resum the coherent nuclear-enhanced power corrections from the final-state partonic scattering in the medium. We find that single and double inclusive open charm production can be suppressed as much as the yield of neutral pions from dynamical high-twist shadowing. Effects of energy loss in p+A collisions are also investigated in the incoherent Bertsch-Gunion limit and may lead to significantly weaker transverse momentum dependence of the nuclear attenuation.

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Ivan Vitev. 2006-05-30. Recent PQCD calculations of heavy quark production. https://doi.org/10.1088/0954-3899%2F32%2F12%2Fs39

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