Thermalization and isotropization of heavy quarks in a non-Markovian medium in high-energy nuclear collisions

We study the isotropization and thermalization of heavy quarks in a non-Markovian medium high-energy nuclear collisions. In particular, we analyze case nonstationary with noise whose time correlator decays as power law (heavy-tailed noise). assume correlations decay an exponent $\ensuremath{\beta}\ensuremath{-}1$, $0\ensuremath{\le}\ensuremath{\beta}<1$; treat $\ensuremath{\beta}$ free parameter. effect memory on via generalized Langevin equation. general, find that slows down dynamics quarks; moreover, happen same timescale once realistic initialization is considered. also that, while charm can be relevant, beauty are hardly affected by quark-gluon plasma phase. Finally, comment estimate ${D}_{s}$ beauty.