Observation of D-0 Meson Nuclear Modifications in Au plus Au Collisions at root(NN)-N-s=200 GeV

We report the first measurement of charmed-hadron (D-0) production via the hadronic decay channel (D-0 -> K- + pi(+)) in Au + Au collisions at root(NN)-N-s = 200 GeV with the STAR experiment. The charm production cross section per nucleon- nucleon collision at midrapidity scales with the number of binary collisions, N-bin, from p + p to central Au + Au collisions. The D-0 meson yields in central Au + Au collisions are strongly suppressed compared to those in p + p scaled by N-bin, for transverse momenta p(T) > 3 GeV/c, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate p(T) is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.