Measurement of heavy flavor production and azimuthal anisotropy in small and large systems with ATLAS

Heavy flavor production and correlation in A+A collisions provide insight into the energy loss mechanism and transport properties of heavy quarks in the QGP. The same measurements in $p$+A collisions could serve as baseline for understanding the observations in A+A collisions. Further more, detailed studies of heavy flavor azimuthal anisotropy in $p$+A may help answering the question whether the observed long-range ``ridge'' correlation arises from hard or semi-hard processes, or if it is the result of mechanisms unrelated to the initial hardness scale. This proceeding summaries ATLAS measurements of heavy flavor production, via their semi-leptonic decay to muons in 2.76 TeV Pb+Pb and $pp$ collisions, and via prompt $D^{0}$ mesons in 8.16 TeV $p$+Pb collisions. The heavy flavor azimuthal anisotropy is studied using their decayed muons in 2.76 TeV Pb+Pb and 8.16 TeV $p$+Pb collisions. Strong heavy flavor production suppression and azimuthal anisotropy are observed in the Pb+Pb collisions, while significant azimuthal anisotropy of heavy-flavor muon is observed without evident production modification in the $p$+Pb collisions.