Heavy flavor production and interactions in hot and cold QCD

Heavy flavor probes are well established probes of the hot system produced in heavy-ion collisions. Open heavy flavor production is better under control in p+p collisions than quarkonium production due to remaining uncertainties in the production mechanism. In heavy-ion collisions, quarkonium suppression and its subsequent regeneration has been described employing a number of approaches including transport models, open quantum systems and statistical hadronization. Many of these approaches employ inputs from lattice QCD on the real and impaginary parts of the quarkonium potential, spectral functions, meson correlators, and dissociation temperatures. Despite different physics inputs, most approaches claim to describe the quarkonium data. Several collaborative efforts have recently been undertaken to clarify the situation with some emphasis on bottomonium production, particularly for the sPHENIX experiment, the last new detector to be deployed at RHIC. These efforts will be discussed and initial comparative results shown. A new DOE topical collaboration to address the subject will also be introduced.