The LHCb Simulation Application, Gauss: Design, Evolution and Experience

The LHCb simulation application, Gauss, is based on the Gaudi framework ; on experiment basic components such as the Event Model ; Detector Description. Gauss also depends on external libraries for the generation of the primary events (PYTHIA 6, EvtGen, etc.) ; on GEANT4 for particle transport in the experimental setup. The application supports the production of different types of events from minimum bias to B physics signals ; particle guns. It is used for purely generator-level studies as well as full simulations. Gauss is used both directly by users ; in massive central productions on the grid. The design ; implementation of the application ; its evolution due to evolving requirements will be described as…