Physics validation : kick-off meeting

1. Physics validation : kick-off meeting Introduction (F. Gianotti ) 15’ Status of simulation validation in the experiments 4 x 20’ + available/to-be-collected test beam data (Speakers from experiments) Plans for “simple benchmarks” validation (J. Beringer) 5’ News from FLUKA (A. Ferrari) 15’ News from G4 (J. Apostolakis) 15’ Organisational matters (F. Gianotti) 15’

2. From T. Wenaus Project Organization Geant4 Project FLUKA Project Experiment Validation MC4LHC Simulation Project Leader Subprojects Framework Geant4 FLUKA integration Physics Validation Shower Param Generator Services WP WP WP WP WP WP Work packages WP WP WP WP WP WP WP WP WP

3. What do we need to validate ? • EM physics (should be ~ok) • HAD physics (calorimetry, tracking, radiation background) • Adequacy and usability of simulation environment: MCTruth, • shower parametrisation, infrastructure (e.g. CPU, memory, interactivity), etc. • Note : -- a lot of work already done in the experiments and by G4 and FLUKA teams • -- continue/finalise this work. In particular, test coherence of results across • experiments and sub-detector technologies. G4, FLUKA Work plan for the Physics validation sub-project circulated and discussed “individually” with you • Validation will be based on : • experiment work : test-beam data, LHC-detector simulations • relevant “simple benchmarks” (e.g. thin targets) : compare G4/FLUKA/data • (J. Beringer from EP-SFT) • collection of most LHC-relevant results from outside LHC (e.g. BaBar, Belle, HARP …) • interactions with G4, FLUKA, framework experts

4. Validation project LHC physics simulation Does this meet LHC physics requirements (e.g. for compositeness) ? Check with (fast ?) simulations that this is good enough Suppose that e.g. for e/ :  (G4-test-beam data)~10% If not : What do we mean by “ validation” ? Needs input/help from the experiment physics groups

5. High-level (somewhat ambitious …) milestones • first cycle of EM physics validation by Summer 2003 • first cycle of HAD physics validation by end 2003 • further iterations in 2004 : ATLAS combined test-beams; framework; etc. • write final document end 2004 ? • What will be the output of the project ? • assess that simulation packages and framework are ok for LHC physics • weaknesses and strengths of the packages (complementarity) ? • uncertainties and inadequacies of the simulation packages •  contribution to systematic errors of measurements when data will be available • define optimised and recommended physics lists, balancing technical performance • against physics • simulation benchmark suite with relevant plots and tests for automatic • (or semi-automatic) validation of future releases • a document (likely with ancillary notes) summarising all the work Note : participation of the 4 experiments to the various WPGs is not uniform (and is time-dependent), but strength of LHC-wide effort is that it allows for some “compensation”

6. Organisational matters • WEB page : Jurg has accepeted to set it up an maintain (thanks !): • http://lcgapp.cern.ch/project/simu/validation • -- links to experiment’s validation pages (if any) and to G4, FLUKA pages • -- minutes of meetings, slides of presentations • -- for each WPG each experiment should post the existing information • (I volunteer to start with the ATLAS part …) • -- collect our (digested) results : plots + few lines of explanation • -- etc. • Mailing list : experiments, G4 team, FLUKA team, Simulation PLs, etc. •  please provide names to Jurg and Fabiola by April 25th • Meeting frequency : • -- one per month (+ coffee-type discussions whenever needed ..) ? • -- proposal : tentatively first Wednesday of the month in the afternoon • -- first meeting : May 14th (or May 7th morning …) ?