- 02 Charm Production in Charged Current Interactions and Charm & Beauty Production in Neutral Current Interactions

The charm and beauty production cross sections in ep neutral current processes and the charm production cross section in ep charged current processes at high Q are measured at HERA. Their determination relies on an inclusive method, where secondary decay vertices are explicitly reconstructed using the H1 vertex detector. The charm and beauty cross sections in neutral current interactions are measured in the kinematic region Q > 150 GeV 2 and 0.1 < y < 0.7 and the results are σ(ep → e′+cc̄X) = 476± 60± 76 pb σ(ep → e′+bb̄X) = 38± 6± 8 pb. The results for the neutral current process are found to be compatible with the prediction of perturbative quantum chromodynamics. In the charged current data an excess over the Standard Model prediction is seen and has been verified by different methods. The excess of events with secondary decay vertices is found in events with transverse momentum of the hadronic system above 40 GeV . At lower values the measurement is in agreement with predictions. If the excess is interpreted as charm contribution, then the measurement of the charm cross section in charged current interactions yields in the kinematic region Q > 150 GeV 2 and 0.1 < y < 0.7 σ(ep → ν̄e c X) = 17.7± 5.5± 2.3 pb. Within the large statistical and systematic errors the measured results are compatible with the predictions.