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Quasi-Particle Model (QPM) has been developed to study charm quark dynamics in ultra-relativistic heavy-ion collisions with good description of D mesons RAA(pT) and v2,3(pT) and leading to the evaluation of the spatial diffusion coefficient Ds(T). With an event-by-event full Boltzmann transport approach followed by a hybrid hadronization via coalescence plus fragmentation, we show RAA(pT), v2(pT) down to pT → 0 for D and B mesons. We find that QPM approach is able to correctly predict first available data on RAA(pT) and v2(pT) of single-electron from B mesons decays measured by ALICE. A significant breaking of the expected scaling of the thermalization time τth with MQ/T is found. Charm quark Ds(T) is about 50% larger than the asymptotic value for MQ → ∞, while the bottom Ds(T) is only 20% higher. In the infinite mass limit the Ds(T) is consistent with recent lQCD calculations with dynamical quarks.

The propagation of heavy quarks (HQs) in the quark-gluon plasma (QGP) is described by means of a full Boltzmann transport approach. The nonperturbative dynamics and the interaction between HQs and the bulk is taken into account by means of a Quasi-Particle Model. Including the intense electromagnetic and vortical fields, we discuss their impact on the directed flow of neutral D mesons at RHIC energy, clarifying the role of this observable in giving information on QGP transport properties. We also show a novel study of the correlations between different flow coefficients of D mesons and soft hadrons at LHC energy within a coalescence plus fragmentation hadronization scheme and including event-by-event initial state fluctuations. This investigations can put further constraints on HQ transport coefficients towards a solid determination in comparison to the lattice QCD calculations.

One of the present challenge for the theoretical understanding of heavy-quark hadronization is represented by the description of the measurements of heavy hadron production in pp, pA and AA collisions from RHIC to top LHC energies. The Λc/D0 ratio observed in AA collisions has a value of the order of the unity, and experimental measurements in pp collisions at both √S = 5.02 TeVs=5.02 TeV and √S = 13 TeVs=13 TeV have shown ratios for charm baryons Λc,Ξc0Λc, Ξc0 and Ωc0Ωc0 respect to D0 meson larger than that measured and expected in e+e−, ep collisions. We present an hadronization mechanism based on the coalescence and fragmentation processes, and the results obtained in AA collisions for D0 and Λc. related baryon to meson ratios at RHIC and LHC. We present moreover results obtained for the charmed hadron production in pp collisions at LHC energies assuming the formation of an hot QCD matter at finite temperature.We calculate the heavy baryon/meson ratio and the pT spectra of charmed hadrons D0. Λc0Λc+ and the recently measured Ξc baryon, finding an enhancement in comparison with the ratio observed for e+e−, ep collisions; with this approach we also predict a significant production of Qc.

We describe the propagation of heavy quarks (HQs), charm and bottom, in the quark-gluon plasma (QGP) by means of a full Boltzmann transport approach including event-by-event fluctuations within a coalescence plus fragmentation hadronization. The non-perturbative dynamics of the interaction between HQs and plasma particles have been taken into account through a Quasi-Particle Model (QPM). We show that the resulting charm in-medium evolution is able to correctly predict simultaneously not only the experimental data for the average D-mesons RAA(pT) and v2,3(pT) at LHC energies but also the extension of the analysis to the event-shape engineeering tecnique that classify events according to magnitude of the second-order harmonic reduced flow vector q2. In the same scheme we show predictions for RAA(pT) of electrons from semi-leptonic B-mesons decays at top LHC energies. Our results entail a determination of Ds which is consistent with the lattice QCD calculations.

In a coalescence plus fragmentation approach we study the pT spectra of charmed hadrons D0, Ds up to about 10 GeV and the Λ+c /D0 ratio from RHIC to LHC energies. In this study we have included the contribution from decays of heavy hadron resonances and also that due to fragmentation of heavy quarks that are left in the system after coalescence. The pT dependence of the heavy baryon/meson ratios is found to be sensitive to the heavy quark mass. In particular we found that the Λc/D0 is much flatter than the one for light baryon/meson ratio like p/π and Λ/K.

We describe the propagation of Heavy quarks (HQs) in the quark-gluon plasma (QGP) within a relativistic Boltzmann transport (RBT) approach. The interaction between heavy quarks and light quarks is described within quasi-particle approach which is able to catch the main features of non-perturbative interaction as the increasing of the interaction in the region of low temperature near TC. In our calculations the hadronization of charm quarks in D mesons is described by mean of an hybrid model of coalescence plus fragmentation. We show that the coalescence play a key role to get a good description of the experimental data for the nuclear suppression factor RAA and the elliptic flow υ2(pT) at both RHIC and LHC energies. Moreover, we show some recent results on the direct flow υ1 and triangular flow υ3 of D meson.

An hadronization model that includes coalescence and fragmentation is used in this work to obtain predictions at both RHIC and LHC energy for light and strange hadrons transverse momentum spectra (π, p, k, Λ) and baryon to meson ratios (p/π, Λ/k) in a wide range of pT. This is accomplished without changing coalescence parameters. The ratios p/π and Λ/K shows the right behaviour except for some lack of baryon yield in a limited pT range around 6 GeV. This would indicate that the AKK fragmentation functions is too flat at pT < 8 GeV.