Production of simulated events for the BaBar experiment by using LCG

We implemented a system, based on the LHC Computing Grid (LCG) tools, to submit full-scale Monte Carlo simulation jobs in the new computing framework of the BaBar experiment. More specifically, the resources of the LCG implementation in Italy, INFN-grid, are used as computing elements (CE) and Worker Nodes (WN). A Resource Broker (RB) specific for the BaBar computing needs was installed. Other BaBar requirements, such as the installation and usage of an object-oriented (Objectivity) database to read detector conditions and calibration constants, were accommodated by using non-gridified hardware in a subset of INFN-grid sites. The BaBar simulation software was packed and installation on grid elements was centrally managed with grid tools. Sites were geographically mapped to Objectivity databases, and conditions were read by the WN either locally or remotely. An LCG user interface (UI) has been used to submit simulation tests by using standard JDL commands. The ROOT I/O output files were retrieved from the WN and stored in the closest Storage Element (SE). Standard BaBar simulation production tools were then installed on the UI and configured such that the resulting simulated events can be merged and shipped to SLAC, like in the standard BaBar simulation production setup. Final validation of the system is being completed.