We calculate the lowest-order charm and beauty parton distribution functions in and fragmentation functions into $D$ and $B$ mesons using the operator definitions of factorized perturbative quantum chromodynamics (QCD). In the vacuum, we find the leading corrections that arise from the structure of the final-state hadrons. Quark-antiquark potentials extracted from the lattice are employed to demonstrate the existence of open heavy flavor bound-state solutions in the quark-gluon plasma in the vicinity of the critical temperature. We provide first results for the in-medium modification of the heavy-quark distribution and decay probabilities in a comoving plasma. In an improved perturbative QCD description of heavy-flavor dynamics in the thermal medium, we combine $D$- and $B$-meson formation and dissociation with parton-level charm and beauty quark quenching to obtain predictions for the heavy-meson and nonphotonic-electron suppression in $\mathrm{Cu}+\mathrm{Cu}$ and $\mathrm{Pb}+\mathrm{Pb}$ collisions at the Relativistic Heavy Ion Collider and the Large Hadron Collider, respectively.

• Received 7 July 2009

DOI:https://doi.org/10.1103/PhysRevC.80.054902