Elliptic anisotropy of open-charm hadrons from parton scatterings in p-Pb collisions at energies available at the CERN Large Hadron Collider

The elliptic azimuthal anisotropy coefficient (v(2)) of open-charm hadrons at midrapidity (vertical bar eta < 1 vertical bar) was studied in p-Pb collisions at root s(NN) = 8.16 TeV using a multiphase transport (AMPT) model including an additional charm quark-antiquark pair production trigger. The model provides a simultaneous description of the measured p(T) spectrum and v(2) of the D-0 meson, as well as the v(2) of light flavor meson K-s(0). We found that the D-0 and K-s(0) v(2) are both significantly affected by different parton scatterings among charm and light quarks. In addition, the predictions for the v(2) of other charm hadrons including D+, D-s(+), and Lambda(+)(c) in p-Pb collisions are given for the first time. The v(2) of open-charm hadrons reasonably follows the number-of-constituent-quark (NCQ) scaling up to 2.5 GeV, strongly indicating the importance of partonic degrees of freedom for the collectivity of heavy flavors in high-multiplicity p-Pb collisions. These findings may hint at the formation of deconfined matter in small collision systems, and provide referential value for future measurements of azimuthal anisotropy at energies available at the CERN Large Hadron Collider.