Measurement of Prompt D-0 Meson Azimuthal Anisotropy in Pb-Pb Collisions at root S-NN=5.02 TeV

Abstract

The prompt D 0 meson azimuthal anisotropy coefficients, v 2 and v 3 , are measured at midrapidity ( | y | < 1.0 ) in Pb-Pb collisions at a center-of-mass energy √ s N N = 5.02 TeV per nucleon pair with data collected by the CMS experiment. The measurement is performed in the transverse momentum ( p T ) range of 1 to 40 GeV / c , for central and midcentral collisions. The v 2 coefficient is found to be positive throughout the p T range studied. The first measurement of the prompt D 0 meson v 3 coefficient is performed, and values up to 0.07 are observed for p T around 4 GeV / c . Compared to measurements of charged particles, a similar p T dependence, but smaller magnitude for p T < 6 GeV / c , is found for prompt D 0 meson v 2 and v 3 coefficients. The results are consistent with the presence of collective motion of charm quarks at low p T and a path length dependence of charm quark energy loss at high p T , thereby providing new constraints on the theoretical description of the interactions between charm quarks and the quark-gluon plasma.