Charmonium, Open Charm and Beauty Production at HERA-B Original Research Article

The HERA-B experiment has collected data on proton-induced collisions with three fixed nuclear targets at 41.6 GeV centre-of-mass energy. Preliminary results of an ongoing, detailed study of charmonium production include the determination of the nuclear dependence of the J/ψ production kinematics (extending for the first time into the negative-xF region) and precise measurements of the feeddown components due to χc, ψ′ and b-hadron decays. A new analysis of the J/ψ decay angular distribution finds significant polarization effects in the low-momentum region, marginally touched by previous experiments. Measurements of the D-meson cross sections are consistent with the absence of nuclear suppression in open charm production.