Figure 4

Combined $v_2^{\rm J/\psi}\{{\rm 2,sub}\}$ coefficients in p--Pb and Pb--p collisions compared to the results in central and semi-central Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ $=$ 5.02 TeV and the transport model calculations for semi-central Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ $=$ 5.02 TeV . The solid line corresponds to the contribution from path-length dependent suppression inside the medium. The band shows the resulting $v_2^{\rm J/\psi}$ including also the recombination of thermalized charm quarks and the feed-down from b-hadron decays assuming thermalization of b quarks