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Thermalization of Heavy Quarks in the Quark-Gluon Plasma

H. van Hees·R. Rapp
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Abstract

Charm- and bottom-quark rescattering in a Quark-Gluon Plasma (QGP) is investigated with the objective of assessing the approach towards thermalization. Employing a Fokker-Planck equation to approximate the collision integral of the Boltzmann equation we augment earlier studies based on perturbative parton cross sections by introducing resonant heavy-light quark interactions. The latter are motivated by recent QCD lattice calculations which indicate the presence of "hadronic" states in the QGP. We model these states by colorless (pseudo-) scalar and (axial-) vector D- and B-mesons within a heavy-quark effective theory framework. We find that the presence of these states at moderate QGP temperatures substantially accelerates the kinetic equilibration of c-quarks as compared to using perturbative interactions. We also comment on consequences for $D$-meson observables in ultra-relativistic heavy-ion collisions.

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H. van Hees, R. Rapp. 2005-03-10. Thermalization of Heavy Quarks in the Quark-Gluon Plasma. https://doi.org/10.1103/physrevc.71.034907

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