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Title: Data-driven extraction of heavy quark diffusion in quark-gluon plasma
Abstract Heavy quark production provides a unique probe of the quark-gluon plasma transport properties in heavy ion collisions. Experimental observables like the nuclear modification factor $$R_\mathrm{AA}$$ R AA and elliptic anisotropy $$v_\mathrm{2}$$ v 2 of heavy flavor mesons are sensitive to the heavy quark diffusion coefficient. There now exist an extensive set of such measurements, which allow a data-driven extraction of this coefficient. In this work, we make such an attempt within our recently developed heavy quark transport modeling framework (Langevin-transport with Gluon Radiation, LGR). A question of particular interest is the temperature dependence of the diffusion coefficient, for which we test a wide range of possibility and draw constraints by comparing relevant charm meson data with model results. We find that a relatively strong increase of diffusion coefficient from crossover temperature $$T_c$$ T c toward high temperature is preferred by data. We also make predictions for Bottom meson observables for further experimental tests.  more » « less
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The European Physical Journal C
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National Science Foundation
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