Simulation Project Organization update & review of recommendations Gabriele Cosmo, CERN/PH-SFT Application Area Internal Review March 31 st, 2005

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 2 Simulation Project  Simulation framework  Interface to multiple simulation engines (Geant4, Fluka) and geometry models exchange  Geant4 team participating  Aligned with and responding to needs from LHC experiments, physics validation, simulation framework  Fluka team participating  Framework integration, physics validation  Garfield team participating  Garfield package integration and support in LCG - SPI  Simulation physics validation  Assess adequacy of simulation and physics environment for LHC and provide the feedback to drive needed improvements  Generator services  Generator libraries; common event files; validation/test suite; development when needed (HepMC, etc.) Witold Pokorski John Apostolakis Alfredo Ferrari Alberto Ribon Paolo Bartalini Rob Veenhof

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 3 Project Organization Simulation Project Leader Framework WP Geant4 WP Fluka WP Physics Validation WP Generator Services WP Subprojects Work packages Geant4 Project Fluka Project Experiment Validation MC4LHC Garfield WP

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 4 Recommendations 2003 review – generator services  “The review recommends to set up a test-bed for the comparison of event generators. This requires a common environment. The data structure must be adequate to support MC-Truth/data comparison. The recommended common format (in memory) is HepMC. Concerning the data format: two implementations should be considered: one for low volume statistics (text based, XML-like or even simpler); one for high volume statistics (Pool/Root based). Both outputs should be easily adaptable to the analysis/visualization/reconstruction system “  The review recommends setting up a test-bed for the comparison of event generators. As the reviewers point out this requires a common environment, and while work is in progress (GENSER, standard event formats) it has to progress further before a common validation framework and test-bed can be established  The project had established a milestone in 2004 to have a proposal for an event generator validation framework  HepMC has been agreed as the file format for the production of common generator particle-level event files  For parton-level generator formats, the XML-based metadata format XMHEP is promoted by the project  For high-volume statistics Pool/Root will be used as persistent generator event storage

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 5 Recommendations 2003 review – physics validation  “ The review encourages the experiments to increase their contribution to the validation activity. It is a unique opportunity for young physicists to contribute to a physics project while being also involved in a hardware development “  The contributions of the experiments to the physics validation activity have been significantly increased in the last 18 months. This effort has produced important feedback for the simulation developers  It is expected that this collaboration will continue in the future

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 6 Recommendations 2003 review – simulation framework  “ The review encourages the development of the VMC with the aim of providing an abstract interface to detector simulation packages and a common interface to the geometry systems used from different simulation engines (Geant4, Fluka, etc). The VMC should also be interfaced to the common solution adopted by GENSER. In the short term, in order to support the physics validation activities one should set up a simulation infrastructure based on Geant4 and Fluka/Flugg. In the medium and long term, the VMC should become the main tool We recommend a discussion with the experiments, Geant4 and Fluka to evaluate their interest in the framework. The priority and manpower should be adjusted according to the outcome of the discussion “  The review noted a lack of strong interest among the experiments in a common simulation framework, while noting that the physics validation project requires the ability to compare multiple simulation engines with the same detector configuration. The project was therefore re-scoped to focus on applying existing tools to meet the specific, immediate needs of the physics validation project – in particular to set up an infrastructure based in Flugg for test beam simulations, and to exchange persistent geometry descriptions through GDML  The review encourages the further development of the existing VMC as a generic simulation framework. This work is continuing outside the scope of the applications area as it has been up to now

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 7 Recommendations 2003 review – Fluka  “ The reviewers were disappointed by the absence of presentation by the Fluka team “  The review came shortly after a Fluka workshop the preceding week and the pressures of priority work following the workshop prevented the planned Fluka talk from taking place  The Fluka team apologizes that this situation prevented them from participating in the review as originally planned

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 8 Simulation Project Milestones :  2003/12: Geant4 release 6.0  2003/12: Simulation physics requirements revisited  2003/12: Simulation framework prototype supporting G4 and FLUKA via FLUGG  2003/12: Proposal for MCDB deployment in the LCG environment  2004/2: LHAPDF generator included in generator library  2004/2: First cycle of hadronic physics validation complete  2004/2: SPI-G4 collaborative infrastructure pilot  2004/3: Agreement on formats for event generator common samples  2004/3: Detector description (GDML) proposal to PEB  2004/03: Geant4 6.1 release - production improvements  2004/4: COMPHEP, ALPGEN and EVTGEN generators included in GENSER  2004/5: Review/prioritization of simple benchmarks for simulation physics validation  2004/6: Proposal for generator event production environment  2004/6: Geant4 6.2 release - resource usage refinements  2004/7: Beta version of MCDB in production in the LCG environment  2004/7: Proposal for an event generator validation framework  2004/9: Agreement on parton-level event generator file format  2004/9: Comparison of LHC calorimeters for EM shower development  2004/10: Geant4 geometry volume registration customization  2004/10:First consolidated G4 acceptance suite for LHC applications  2004/12: Generator production framework, beta  2004/12: Geant4 physics model prototype concluded  2004/12: Second iteration of hadronic physics validation complete  2004/12: Simulation test and benchmark suite available  2004/12: Geant4 7.0 release - physics models and geometry  2004/12: Geant4 validation in LHC production  2005/06: Final physics validation document complete

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Mar 2005 Slide 9 Simulation Project Major Milestones : 2004  2004/2: First cycle of hadronic physics validation complete  2004/2: SPI-G4 collaborative infrastructure pilot  2004/3: Agreement on formats for event generator common samples  2004/5: Review/prioritization of simple benchmarks for simulation physics validation  2004/6: Geant4 6.2 release - resource usage refinements  2004/7: Beta version of MCDB in production in the LCG environment  2004/9: Agreement on parton-level event generator file format  2004/9: Comparison of LHC calorimeters for EM shower development  2004/10:First consolidated G4 acceptance suite for LHC applications  2004/12: Generator production framework, beta release  2004/12: Second iteration of hadronic physics validation complete  2004/12: Simulation test and benchmark suite available  2004/12: Geant4 7.0 release - physics models and geometry  2004/12: Geant4 validation in LHC production  2005/06: Final physics validation document complete