Simulation Project Organization update & review of recommendations Gabriele Cosmo, CERN/PH-SFT Application Area Internal Review September 19 th, 2006

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 2 Simulation Project  Simulation framework  Interface to multiple simulation engines (Geant4, Fluka) and geometry models exchange (GDML), MC truth handling, Python interfaces  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; validation/test suite; development when needed (HepMC, etc.); common event files Witold Pokorski John Apostolakis Alfredo Ferrari Alberto Ribon Witold Pokorski as of 15-Sep-06 Rob Veenhof

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 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, Sep 2006 Slide 4 Recommendations 2005 review – generator services  “ The size of the complete GENSER package is becoming too big to be handled efficiently. Therefore the review recommends introducing more granular packaging options for distribution”  A modular way for downloading also individual MC packages has been introduced since release of GENSER. A Python script allows for the selection and automatic download from the Web  “The situation with HepMC is still unclear and needs to be re- evaluated once the new release is used in production by all experiments”  HepMC has been agreed as the file format for the production of common generator particle-level event files. It is also adopted for later stages in simulation and reconstruction  Since January 2006 the HepMC package is released and maintained among the external packages in the LCG AFS area, now released and distributed independently. Lynn Garren (FNAL) has joined the effort undertaking the support for HepMC. HepMC is now organised in the context of LCG and a dedicated Savannah portal is set  From the future version of HepMC (2.X), the package will become a standalone product with no external dependencies  Agreement among experiments to consider the standalone HepMC as the reference version

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 5 Recommendations 2005 review – physics validation - 1  “A continuing common effort together with the experiments to validate the packages against test beam data and simple benchmark processes ”  Results from test-beam setups of 2004 have been obtained and presented (ATLAS, CMS) others are expected soon (ATLAS)  New releases of Geant4 are promptly validated against test-beam data (ATLAS-HEC); such process has been established since 2005  “Continuation of the Fluka validation, especially of the hadronic physics”  Milestones for simple benchmarks and test-beam setups are defined and in advanced state. Fluka and Geant4 are the MC engines being verified  “To install a central repository for the validation results”  The code repository for the simple benchmarks is in place and populated. For the test-beam setups, work is in progress for correcting the data from instrumental effects and allow their use for standalone validation

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 6 Recommendations 2005 review – physics validation - 2  “To revisit together with the experiments the effect on systematic uncertainties for future measurements, due to the present simulation uncertainties, as observed by the ongoing validation studies”  These evaluations are undergoing in the experiments. Considerable effort has been put and is still ongoing for understanding, improving and verifying the hadronic shower shapes  Concern: “The reduction in manpower of 2.3 to 0.8 FTE in the physics validation of Geant4 is very worrying. If Geant4 can argue that this is essentially a CERN responsibility we recommend that the LCG tries to improve the manpower situation”  The average manpower in the last 12 months has been of 2.3 FTE, which corresponds to the current figure  Manpower projection for the next 6 months: 1.9 FTE

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 7 Concerns 2005 review – simulation framework  “ Concern that the subproject is carried by less than one FTE. In the long run this may be insufficient ”  The project has been reinvigorated with new manpower during 2006 reaching an average of 1.3 FTE in the past 12 months and currently at 1.8 FTE  Helped to successfully achieve most of the milestones assigned to the Project  Manpower projection for the next 9 months: 1.4 FTE

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 8 Recommendations 2005 review – Fluka  “FLUKA installation together with source code should be made available very soon”  “Distribution of FLUKA should make use of the SPI tools, like other AA related software products”  The source code of Fluka is available to CERN and INFN researchers since July The source of the most recent release (fluka2006.3) will be open to all scientific Institutions  AFS space has been setup for the installation of the Fluka package in the LCG area  The most recent version of Fluka (2006.3) will be soon installed

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 9 Recommendations 2005 review – Geant4  “Any concerns on the validity of the physics results should be brought forward in the validation subproject ”  Feedback for validation studies done in the experiments is reported in the Physics Validation meetings monthly organised by the Physics Validation subproject in coordination with the physics validation responsibles in the experiments

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 10 Simulation Project major Milestones :  2005/02: VD502 - Review/prioritization os simple benchmarks for physics validation  2005/05: VD508 - First results of background radiation studies in Geant4  2005/06: VD512 - New validation results on longitudinal shower shapes in Geant4  2005/06: SF515 - GDML schema extension to support divisions and reflections  2005/06: SF516 - Feasibility study of Pool/Root-based geometry persistency in Geant4  2005/06: SF517 - Python implementation of GDML writers for Geant4 and Root  2005/06: G Geant4 7.1 public release  2005/07: G Tutorial on Geant4 at CERN and move of Geant4 code repository to IT service  2005/09: VD rd simple benchmark completed  2005/09: VD524 - Validation of Fluka against ATLAS TileCal test-beam  2005/09: GS527 - Procedure for light GENSER releases  2005/09: SF530 - Flugg application to ATLAS TileCal test-beam simulation  2005/10: G Improved Geant4 regression suite for release validation and testing infrastructure  2005/10: VD532 - First results of ATLAS combined and 2004 test-beams data comparisons  2005/12: GS535 - Generator level production framework: production quality release  2005/12: GS536 - Evaluation of possible migration of HepMC to LCG  2005/12: SF537 - Introduction of modularization of GDML files  2005/12: SF538 - Proposal for universal handling of Monte Carlo truth  2005/12: GF540 - Interface in Garfield with new version of Magboltz  2005/12: GF541 - Interface in Garfield with new version of Heed  2005/12: G Geant4 8.0 public release  2006/03: GS602 - Introduction of MCDB GRID certificates and management of large files  2006/05: G Developments for Geant4 8.1 public release  2006/06: SF608 - Refinements to GDML schema to support user extensions of elements  2006/06: VD617 - Investigation of corrections to test-beam data for validation of stand-alone simulation engines  2006/12: G Report on the main physics effects responsible for hadronic shower development in Geant4  2007/06: VD703 - Application of corrections to test-beam data to the LHC calorimeter test-beam simulations  2007/06: GS701 - Generator level validation framework production version  2007/09: GS702 - Pythia 8 production release

Gabriele Cosmo, CERN/PH-SFT AA Internal Review, Sep 2006 Slide 11 Current LCG simulation manpower Simulation framework1.80 (1.40) Geant47.20 (7.70) Infrastructure, performance, management (approx)2.05 EM / Hadronic physics effort (approx)3.90 Tracking, biasing, geometry (approx)1.25 CERN staff (3.80), CERN fell./assoc. (3.40) Physics validation2.30 (1.90) Validation specific to experiments 1.50 Generator services3.30 (3.50) management, documentation/release (LCG CERN, Florida U.) 1.20 GENSER dev., Validation, MCDB (LCG Russia, Italy) 1.85 Production Framework (LCG Spain) 0.25 Fluka0.00 Garfield1.00 (0.80) Management0.25 Total As of Sep 15