[ Software Requirements Document ] [ Users Requirements Document ] [ Traceability Matrix ] [ Planned Activities ]

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The Geant4 geometry working group is responsible for the development and maintenance of the geometry modeller in the Geant4 toolkit. The development in the Geant4 geometry modeller spawns within the following areas: geometrical shapes, navigation algorithms, detector modelling techniques (volumes positioning), transportation in field and importance biasing techniques.

The Working Group is currently composed by:

• John Apostolakis, CERN (coordinator - field, navigation)
• Gabriele Cosmo, CERN (deputy-coordinator - management, navigation, volumes)
• Pedro Arce Dubois, CIEMAT (navigation, volumes)
• Makoto Asai, SLAC (biasing, volumes)
• Rodrigo Daniel Castro, Universidad de Buenos Aires (field)
• Andrei Gheata, CERN (navigation)
• Vladimir Grichine, Russian Academy of Sciences (solids)
• Ivana Hrivnacova, IN2P3 Orsay (g3tog4, volumes)
• Guilherme Lima, FNAL (navigation, solids)
• Lucio Santi, Universidad de Buenos Aires (field)
• Raman Sehgal, BARC (solids)
• Evgueni Tcherniaev, Lebedev Institute (solids)
• Sandro Christian Wenzel, CERN (navigation, solids)

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Development

Detector Description

• GDML - Geometry Description Markup Language: specifications
  - G.Cosmo

Solids

• Twisted shapes (PDF), by O.Link
  - Contact: V.Grichine
• Using the Surface-Checker test (PDF), by O.Link
  - Contact: T.Nikitina

Cuts by detector region

• Category class diagrams: Geometry, Processes, Track.
• Use cases through interaction diagrams:
  1. Standard initialisation (Define region, set cuts, build physics table)
  2. Alternative initialisation (Define production cut, add/remove region)
  3. Step computation and tracking (PostStepDoIt, handling of material-cut-couples)

Parallel Navigation

• Design description.
• Category class diagrams: Multiple Navigators, Path Finder.
• Use cases through interaction diagrams:
  1. Standard initialisation
  2. Tracking initialisation
  3. Stepping interaction

Event biasing

• Latest development in importance sampling and scoring: documentation (by M.Dressel)
  - Contact: A.Howard
• Scoring and geometrical importance sampling use cases (by M.Dressel)
  - Contact: A.Howard

Tallies

• User Requirements Document (PDF, v.0.2), by G.Daquino
  - Contact: A.Howard

Code Reviews

• Field propagation, October 2009

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LXR Code Browsing

• Geometry module
• Transportation module

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Talks

• Reference-counted touchables proposal (PPT)
  - R.Chytracek, May 2001
• Importance Sampling (geometrical splitting and Russian Roulette) (PDF)
  - M.Dressel, November 2002

Recent Publications

• Parallel Geometries, IEEE-2008 (May 2008)
• Regular Navigation, IEEE-2008 (May 2008)
• Geometry Modeler Updates, CHEP-2006 (May 2006)
• Geometry Modeler, IEEE-2004 (October 2004)

Geometry Tutorial

• School course (February 2010), based on Geant4 9.3 release
  • Part 1 - Part 2 - Part 3 - Part 4 - Part 5