1. Calorimeter Simulation Infrastructure Norman Graf Arlington ‘03

2. 2 Detector Issues Current simulations are good enough for many studies, but room for improvement. Current simulations are good enough for many studies, but room for improvement. Need more detailed/realistic subdetector designs. Need more detailed/realistic subdetector designs. Current detectors are floating cylinders! Current detectors are floating cylinders! Luminosity monitors and masks neglected. Luminosity monitors and masks neglected. Fairly simple absorber/readout sandwich. Fairly simple absorber/readout sandwich. Only projective tower geometry supported. Only projective tower geometry supported. Subdetector integration needs attention. Subdetector integration needs attention.

3. 3 GEANT4 Release 5.0 out in December 2002. Release 5.0 out in December 2002. Default Physics Process Lists are available. Default Physics Process Lists are available. Patches & upgrades to hadronic models. Patches & upgrades to hadronic models. SLAC installation includes GEISHA fixes. SLAC installation includes GEISHA fixes. Working on support for more complicated geometries. Evaluating GDML as replacement for existing XML. Working on support for more complicated geometries. Evaluating GDML as replacement for existing XML. T. Abe working on TGeom interface. T. Abe working on TGeom interface. see talk in simulation session see talk in simulation session

4. 4 GEANT4 cooperation Working with European colleagues to define common elements. Working with European colleagues to define common elements. Active work on a common simulation output format (LCIO talk by T. Johnson). Active work on a common simulation output format (LCIO talk by T. Johnson). Discussing geometry packages. Discussing geometry packages. Looking for best aspects of current implementations Looking for best aspects of current implementations flexibility of LCD system vs detail of Mokka flexibility of LCD system vs detail of Mokka

5. 5 Detector Models Our Calorimeter designs need work! Our Calorimeter designs need work! SD has mistake in gap between EM & HAD. SD has mistake in gap between EM & HAD. replace with strongback followed by readout. replace with strongback followed by readout. LD needs a hadronic calorimeter! LD needs a hadronic calorimeter! First pass T detector to allow some comparisons to TESLA studies. First pass T detector to allow some comparisons to TESLA studies. Decouple algorithm from detector. Decouple algorithm from detector. Need work on far forward region! Need work on far forward region! Luminosity monitors & instrumented masks! Luminosity monitors & instrumented masks! What is effect of beam crossing angle! What is effect of beam crossing angle!

6. 6 BDS Simulation (GEANT3)

7. 7 BDS in GEANT4 Full JLC BDS implemented in G4 by Tokyo group (M. Iwasaki). Full JLC BDS implemented in G4 by Tokyo group (M. Iwasaki). Parses machine decks to create geometries. Parses machine decks to create geometries. Incorporates transport code from G. Blair. Incorporates transport code from G. Blair. Fruitful collaboration with T. Maruyama at ISG at KEK in December. Fruitful collaboration with T. Maruyama at ISG at KEK in December. Look forward to full incorporation to allow detailed studies of far forward calorimetry. Look forward to full incorporation to allow detailed studies of far forward calorimetry.

8. 8 Reconstruction & Analysis Huge increase in the number of analyses since the Chicago meeting. Huge increase in the number of analyses since the Chicago meeting. See all the following talks. See all the following talks. Energy flow framework and object definitions evolving. Energy flow framework and object definitions evolving. e.g. electron and muon ID. e.g. electron and muon ID. Full reconstruction analyses starting. Full reconstruction analyses starting. Cells  Clusters  cluster ID  EFO  analysis Cells  Clusters  cluster ID  EFO  analysis Tracks+Cells  EFO  analysis Tracks+Cells  EFO  analysis Challenge is to accommodate disparate packages into common framework. Challenge is to accommodate disparate packages into common framework.

9. 9 Energy Flow Would still like to see “smoking gun” analysis which clearly demonstrates that EFlow calorimetry is necessary. Would still like to see “smoking gun” analysis which clearly demonstrates that EFlow calorimetry is necessary. Infrastructure to allow ganging of cells at analysis level available. Infrastructure to allow ganging of cells at analysis level available.  systematic segmentation studies  systematic segmentation studies Would like to see dependencies on B and R. Would like to see dependencies on B and R. Developing ~fast simulation package to allow fast prototyping of designs. Developing ~fast simulation package to allow fast prototyping of designs. Crystals anyone? Crystals anyone?

10. 10 Backgrounds Essential that detector design be robust against machine backgrounds. Essential that detector design be robust against machine backgrounds. Crucial to undertake physics studies in the correct context of irreducible physics backgrounds. Crucial to undertake physics studies in the correct context of irreducible physics backgrounds. Can no longer simply float k T to get 2 jets! Can no longer simply float k T to get 2 jets! Correctly simulate and overlay backgrounds on signal, event-by-event. Correctly simulate and overlay backgrounds on signal, event-by-event.

11. 11 Machine backgrounds e+e- pairs from beam-beam interactions (T. Maruyama) e+e- pairs from beam-beam interactions (T. Maruyama) Generated large samples of events, simulated in LD and SD Generated large samples of events, simulated in LD and SD Have added beam train’s worth to some signal events, started analyses. Have added beam train’s worth to some signal events, started analyses. Muons from collimator halo (L. Keller) Muons from collimator halo (L. Keller) Event samples generated Event samples generated Will be simulated and available for overlay soon. Will be simulated and available for overlay soon.

12. 12 Underlying Physics Processes Dominant background due to  hadrons resulting from beam- and brems-strahlung photons. Dominant background due to  hadrons resulting from beam- and brems-strahlung photons. Extensively studied at LEPII, particularly by OPAL. Extensively studied at LEPII, particularly by OPAL. Event generators usually considered: Event generators usually considered: PHOJET PHOJET PYTHIA PYTHIA HERWIG HERWIG

13. 13  Generators Latest version of PYTHIA includes improved support for  processes. Latest version of PYTHIA includes improved support for  processes. Use CIRCE to provide input  spectrum. Use CIRCE to provide input  spectrum. PYTHIA allows event-by-event specification of cms energy. PYTHIA allows event-by-event specification of cms energy. Generate inclusive  processes. Generate inclusive  processes. Large samples of events have been simulated with SD and LD. Large samples of events have been simulated with SD and LD. Good enough for first pass analyses. Good enough for first pass analyses.

14. 14 Testbeam Support Working on GEANT4 package to support generic testbeam setups. Working on GEANT4 package to support generic testbeam setups. Flexible geometry setup, hits, digitization. Flexible geometry setup, hits, digitization. AIDA Interface for analysis. AIDA Interface for analysis. Aid in design of R&D prototypes. Aid in design of R&D prototypes. Depth, lateral extent, etc. Depth, lateral extent, etc. Study thresholds, ADC bits, dead channels, etc. Study thresholds, ADC bits, dead channels, etc. Useful for analysis of TB data. Useful for analysis of TB data.

15. 15 Summary We need to improve the calorimeter designs by making them more realistic. We need to improve the calorimeter designs by making them more realistic. Far-forward calorimetry missing! Far-forward calorimetry missing! Tools are available to study backgrounds. Tools are available to study backgrounds. Many reconstruction & analysis efforts ongoing, challenge is to integrate them into common framework. Many reconstruction & analysis efforts ongoing, challenge is to integrate them into common framework. Many projects ongoing, plenty of places to plug in and contribute! Many projects ongoing, plenty of places to plug in and contribute!