Heavy-Flavor Probes of Hot QCD Matter

The heavy charm and bottom quarks, and their bound states, are versatile probes of the hot medium created in high-energy heavy-ion collisions. At low momentum, open heavy-flavor particles serve as "Brownian Markers" which allow to extract a fundamental transport parameter of the medium, the heavy-flavor diffusion coefficient. At intermediate momenta, heavy quarks give unique insights into the transition regime from elastic to radiative interactions, as well as into the nature of hadronization. Furthermore, the in-medium spectroscopy of heavy quarkonia, as inferred from transport theoretical approaches, allows to constrain the in-medium QCD force. We emphasize the need for a common theoretical framework to simultaneously treat the open and hidden heavy-flavor sectors, and discuss how such a framework can unravel microscopic mechanisms that drive the properties of the strongly coupled quark-gluon plasma and its hadronization.