Temperature dependence of heavy quark diffusion from 2+1 lattice QCD

We present new lattice results for the heavy quark diffusion coefficient in 2+1 flavor QCD in the temperature range from 163 MeV up to 10 GeV. Compared to previous lattice calculations with unphysical light quark masses, we consider near-physical values and a much wider temperature range. Our results for the spatial heavy diffusion coefficient near the crossover temperature are considerably smaller than the estimates obtained by comparing phenomeno-logical models with experimental data and by T-matrix calculations, and are close to the AdS/CFT limit. At high temperatures, however, the spatial heavy diffusion coefficient increases and approaches the NLO weak coupling prediction within the estimated errors. We also find that the dependence of the spatial heavy quark diffusion coefficient on the heavy quark mass MQ on the lattice is weaker compared to the model calculations.