  Production, elliptic flow and the nuclear modification factor of charm and
bottom quarks are studied in central and non-central heavy-ion collisions at
RHIC and LHC using the partonic transport model Boltzmann Approach of
MultiParton Scatterings (BAMPS). Employing an initial heavy quark yield
obtained with PYTHIA the full space-time evolution of charm and bottom quarks
in the quark-gluon plasma (QGP) is carried out with BAMPS, taking also
secondary production in the QGP into account. Only elastic collisions of heavy
quarks with particles from the medium cannot describe the experimentally
observed elliptic flow and nuclear modification factor. However, using an
improved Debye screening and the running coupling yields a result which is much
closer to data.
