Open charm production and asymmetry in p Ne collisions at s NN = 68.5 Ge V

Abstract

A measurement of D0 meson production by the LHCb experiment in its fixed-target configuration is presented. The production of D0 mesons is studied with a beam of 2.5 TeV protons colliding on a gaseous neon target at rest, corresponding to a nucleon–nucleon centre-of-mass energy of sNN=68.5GeV. The sum of the D0 and D¯0 production cross-section in pNe collisions in the centre-of-mass rapidity range y⋆∈[-2.29, 0] is found to be σD0y⋆∈[-2.29, 0]=48.2±0.3±4.5μb/nucleon where the first uncertainty is statistical and the second is systematic. The D0-D¯0 production asymmetry is also evaluated and suggests a trend towards negative values at large negative y⋆. The considered models do not account precisely for all the features observed in the LHCb data, but theoretical predictions including 1% intrinsic charm and 10% recombination contributions better describe the data than the other models considered.