Langevin dynamics of heavy quarks in a soft-hard factorized approach

Abstract

By utilizing a soft-hard factorized model, which combines a thermal perturbative description of soft scatterings and a perturbative QCD-based calculation for hard collisions, we study the energy and temperature dependence of the heavy quark diffusion coefficients in Langevin dynamics. The adjustable parameters are fixed from the comprehensive model-data comparison. We find that a small value of the spatial diffusion coefficient at transition temperature is preferred by data $$2\pi TD_{s}(T_{c}) \simeq 6$$ 2 π T D s ( T c ) ≃ 6 . With the parameter-optimized model, we are able to describe simultaneously the prompt $$D^{0}$$ D 0 $$R_{\mathrm{AA}}$$ R AA and $$v_{\mathrm{2}}$$ v 2 data at $$p_{\mathrm{T}}\le 8$$ p T ≤ 8 GeV in Pb–Pb collisions at $$\sqrt{s_{\mathrm{NN}}}=2.76$$ s NN = 2.76 and $$\sqrt{s_{\mathrm{NN}}}=5.02$$ s NN = 5.02 TeV. We also make predictions for non-prompt $$D^{0}$$ D 0 meson for future experimental tests down to the low momentum region.