Heavy flavour kinetic equilibration in the confined phase

Understand

By making use of a non-perturbative definition of a momentum diffusion coefficient as well as Heavy Meson Chiral Perturbation Theory, we investigate the Brownian motion and kinetic equilibration of heavy quark flavours deep in the confined phase.

• It appears that the momentum diffusion coefficient can be expressed in terms of known low-energy constants; it increases rapidly at temperatures above 50 MeV, behaving as ~ T^7/F_pi^4 for m_pi / pi << T << F_pi, where m_pi and F_pi are the pion mass and decay constant, respectively.
• The early increase may suggest a broad peak in kappa/T^3 around the QCD crossover.
• For a more detailed understanding the computation could be generalized in a number of ways.