Charm quark fugacity in hot QCD

We study the fugacity of charm quarks in hot QCD from the quasiparticle perspective. The system is described in terms of dynamical quarks and gluons dressed by the effective temperature-dependent masses which link the thermodynamics of the model to the lattice QCD data for Nf = 2 + 1. We insert the charm quarks „by hand” and investigate how their scatterings with the quasiparticles affect the charm quark fugacity in a viscous medium expanding in all spatial dimensions and in the perfect fluid propagating longitudinally. We find that the charm quark fugacity strongly depends on the evolution of the deconfined matter at early stages while behaving universally close to the QCD crossover.