GLAST Geant4 Simulation
Transcript
GLAST Geant4 Simulation
GLAST Italian Software Roma, 4 maggio 2001 GLAST Geant4 Simulation F.Longo D. Favretto R.Giannitrapani 1 GLAST Italian Software Roma, 4 maggio 2001 Introduction • Simulation effort • GammaRayTel advanced example in the Geant4 3.0 release • XML - Geant4 visitor • Hit class 2 GLAST Italian Software Roma, 4 maggio 2001 Simulation Effort • Design and optimise the detector • Develop and test the reconstruction and analysis programs • Interpret the experimental data 3 GLAST Italian Software Roma, 4 maggio 2001 Why Geant4? • Toolkit for the simulation of the passage of particles through matter. Various application areas • Complete set of tools for all the domains of detector simulation • Set of Physics Processes across a wide energy range • Advanced Software Engineering techniques and Object Oriented technology • Transparency of the physics implementation with the possibility of validating the physics results. 4 GLAST Italian Software Roma, 4 maggio 2001 GammaRayTel example • • • • • • • Geometry Hits Classes Physics Digitizer Module Trigger Evaluator Astrophysics Persistency Analysis tools 5 GLAST Italian Software Roma, 4 maggio 2001 Present Situation • Single “GLAST ”Tower • Silicon Tracker, Plastic Scintillator Anticoincidence, CsI Calorimeter • Standard Electromagnetic Processes • Hits Persistency (ASCII format) • Hits Analysis on-line with AIDA-Lizard • Setup Visualization with OpenGL, PostScript and VRML http://www.ge.infn.it/geant4/lowE/examples/gammaray_telescope/index.html 6 GLAST Italian Software Roma, 4 maggio 2001 VRML visualization • Simple example of VRML file 7 GLAST Italian Software Roma, 4 maggio 2001 Hits & SD classes • • • • Tracker, ACD and Calorimeter volumes as sensitive detectors ACD information (side and energy release) CAL information (plane, bar, position, energy release) TKR information (plane, strip, position, energy release) 8 GLAST Italian Software Roma, 4 maggio 2001 Particle Generation • • • • Simple Generator with Messenger Isotropic or point source Spectral Options Integration with GSPM 9 GLAST Italian Software Roma, 4 maggio 2001 Analysis Tools • • • • • • Released version with Lizard using AIDA 1d and 2d histograms More than one histogram (with some difficulties) Single or multiple views Run-based or event-based Messenger to choose modality 10 GLAST Italian Software Roma, 4 maggio 2001 Analysis Tools 11 GLAST Italian Software Roma, 4 maggio 2001 Projects • Digitizer Module • FITS persistency • ESA space modules 12 GLAST Italian Software Roma, 4 maggio 2001 Digits • • • • ReadOut Geometry utilization for the Tracker Digitizer module for TKR and CAL Example of Trigger function of EventAction class Example of “Digitization” inside G4 13 GLAST Italian Software Roma, 4 maggio 2001 FITS persistency • Astrophysical Standard Type for DATA format • Great Utility for real users (possibility to use standard external analysis tools) • Link with NASA FITSIO libraries 14 GLAST Italian Software Roma, 4 maggio 2001 XML client • XML as the description format of the geometry • G4GDD XML visitor inside DetectorConstruction class • Logical Volumes, Physical positioning and volume hierarchy represented • With the use of a GEANT4 messenger it is possible to change runtime both the XML file that contains the geometric representation and the mother volume to simulate – This permits to simulate, without any need to exit from the simulation, any part of the detector independently 15 GLAST Italian Software Roma, 4 maggio 2001 XML client 16 GLAST Italian Software Roma, 4 maggio 2001 XML client 17 GLAST Italian Software Roma, 4 maggio 2001 XML client 18 GLAST Italian Software Roma, 4 maggio 2001 Hit Class • • • • • Sensitive Volumes (from XML) Pre and Post Step Point Step length Energy deposition along the step Volume identifier (from XML) 19 GLAST Italian Software Roma, 4 maggio 2001 Conclusions • Ready for Validation • Gaudi Integration • Event Generator Interface 20