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 (v2) of open-charm hadrons at midrapidity (|η<1|) was studied in p-Pb collisions at sNN=8.16 TeV using a multiphase transport () model including an additional charm quark–antiquark pair production trigger. The model provides a simultaneous description of the measured pT spectrum and v2 of the D0 meson, as well as the v2 of light flavor meson Ks0. We found that the D0 and Ks0 v2 are both significantly affected by different parton scatterings among charm and light quarks. In addition, the predictions for the v2 of other charm hadrons including D+, Ds+, and Λc+ in p-Pb collisions are given for the first time. The v2 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. Published by the American Physical Society 2024