Exploiting the Grid to Simulate & Design the LHCb Experiment

1. Exploiting the Grid to Simulate & Design the LHCb Experiment Compute Element Storage Element Calorimeters Muon Detector mss Local disk Yoke Tracker Job Shielding Data globus-url-copy Data Coil register-local-file publish CERN TESTBED Replica Catalog (NIKHEF) RICH-2 REST-OF-GRID Moun replica-get Vertex Job Storage Element RICH-1 Data 10 mm LHCb is a particle physics experiment which will study the subtle differences between matter and antimatter. The design and construction of the experiment is being undertaken by 500 scientists from 48 institutes in 14 countries around the world. The experiment will be located 100m underground at the Large Hadron Collider (27km circumference) which is being built at CERN in Geneva. Over 1000 million short lived particles of matter and antimatter called B and B-bar mesons (which contain the b quark) will be studied at LHCb each year. In order to design the detector and to understand the physics, many millions of simulated events also have to be produced. We are using Grid technology so that we can use computing resources distributed around the world to satisfy our requirements. A prototype system has been built which is based on our existing software. DataGrid middleware is being deployed as it becomes available. In this way, LHCb is able to produce simulated datasets as well as feeding back our experience and ideas into the design of the Grid. Computing centres on the Grid are gradually being added into the LHCb production system as they come online. Currently, these include: CERN, FRANCE - IN2P3(Lyon), ITALY – Bologna, NETHERLANDS – NIKHEF, as well as the EU DataGrid Testbed. In the UK, LHCb computing and software centres are sited at the Universities ofBristol, Cambridge, Edinburgh, Glasgow, Imperial College, Liverpool & Oxford and Rutherford Appleton Laboratory.