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The second (v 2) and third (v 3) flow harmonic coefficients of J/ψ mesons are measured at forward rapidity (2.5 < y < 4.0) in Pb-Pb collisions at √ s NN = 5.02 TeV with the ALICE detector at the LHC. Results are obtained with the scalar product method and reported as a function of transverse momentum, p T , for various collision centralities. A positive value of J/ψ v 3 is observed with 3.7σ significance. The measurements, compared to those of prompt D 0 mesons and charged particles at mid-rapidity, indicate an ordering with v n (J/ψ) < v n (D 0) < v n (h ±) (n = 2, 3) at low and intermediate p T up to 6 GeV/c and a convergence with v 2 (J/ψ) ≈ v 2 (D 0) ≈ v 2 (h ±) at high p T above 6-8 GeV/c. In semicentral collisions (5-40% and 10-50% centrality intervals) at intermediate p T between 2 and 6 GeV/c, the ratio v 3 /v 2 of J/ψ mesons is found to be significantly lower (4.6σ) with respect to that of charged particles. In addition, the comparison to the prompt D 0-meson ratio in the same p T interval suggests an ordering similar to that of the v 2 and v 3 coefficients. The J/ψ v 2 coefficient is further studied using the Event Shape Engineering technique. The obtained results are found to be compatible with the expected variations of the eccentricity of the initial-state geometry.

The production yield of prompt D mesons and their elliptic flow coefficient v 2 were measured with the Event-Shape Engineering (ESE) technique applied to mid-central (10-30% and 30-50% centrality classes) Pb-Pb collisions at the centre-of-mass energy per nucleon pair √ s NN = 5.02 TeV, with the ALICE detector at the LHC. The ESE technique allows the classification of events, belonging to the same centrality, according to the azimuthal anisotropy of soft particle production in the collision. The reported measurements give the opportunity to investigate the dynamics of charm quarks in the Quark-Gluon Plasma and provide information on their participation in the collective expansion of the medium. D mesons were reconstructed via their hadronic decays at mid-rapidity, |η| < 0.8, in the transverse momentum interval 1 < p T < 24 GeV/c. The v 2 coefficient is found to be sensitive to the event-shape selection confirming a correlation between the D-meson azimuthal anisotropy and the collective expansion of the bulk matter, while the per-event D-meson yields do not show any significant modification within the current uncertainties.

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