1. Advanced Examples Maria Grazia Pia INFN Genova on behalf of the Advanced Examples[not yet]Working Group http://www.ge.infn.it/geant4/examples/

2. Background • Geant4/examples/advanced existing since the first Geant4 release in 1998 • …but empty • First two advanced examples proposed in 2000 • xray_telescope • gammaray_telescope • Now 14 examples released + 1 to be released in 7.0 • Established collaboration between Geant4 and analysis groups • constructive mutual help with AIDA and Anaphe/PI, JAS teams • 23 Geant4 collaborators involved • + 1 former collaborator and various external contributors • Wide network of contacts with users • Often volunteering to contribute new examples

3. Astrophysics / Space Science cosmicray_charging gamma-ray_telescope X-ray_telescope HEP composite_calorimeter lAr_calorimeter RICH underground_physics Next release air_shower Medical Physics brachytherapy hadrontherapy medical_linac purging_magnet Shielding radioprotection Tiara Spectroscopy X-ray_fluorescence Topics

4. http://www.ge.infn.it/geant4/examples

5. Stefano Agostinelli Henrique Araujo Pablo Cirrone Giacomo Cuttone Giuseppe Daquino Maria Catarina Espirito Santo Franca Foppiano Stefania Garelli Patricia Goncalves Susanna Guatelli Alex Howard Francesco Longo Ana Keating Susanne Larsson Alfonso Mantero Lorenzo Moneta Jakub Moscicki Andreas Pfeiffer Maria Grazia Pia Michela Piergentili Alberto Ribon Giovanni Santin Bernardo Tome Patricia Mendez Lorenzo Sajan Easo (not a Geant4 member) Former members and external contributors Advanced Examples“Working Group” Members • Regular WG meetings • WG mailing list • Geant4-advanced-examples@cern.ch • Common software process • Overall coordination • Shared vision and goals

6. Vision • Provide real-life examples to users • Realistic applications of Geant4 “on the field” • Developed together by experts in the experimental domain and in Geant4 • Useful to users to get started in a typical experimental application domain • Provide feedback to Geant4 developers • How well Geant4 fulfills the requirements of a specific experimental domain • identify new requirements, improvements needed etc. • How well Geant4 works in a realistic environment • physics, performance etc. • Educate developers to a healthy software process • Learn the discipline of a full cycle of software development

7. Role • A strategical area of Geant4 • Geant4 shifting more and more from development to application • Understanding experimental needs is crucial • if we want to provide a tool responding to the needs of the scientific community • User support is a significant workload for developers • Examples alleviate the developers’ workload • Facilitate contacts and open communication with the user community • Get in touch with a (new) experimental environment

8. The process of creating an example • Normal procedure • We (developers) propose the creation of a new advanced example, in an area where user support is needed • Goal: offer a broad coverage of experimental domains • “Motivate” a team to work together on a simplified version of a real-life application • A new attitude recently showing up… • Users contact us proposing to contribute to a new advanced example • New examples in preparation announced to the TSB • Directory in cvs agreed with the Release Manager • Development process guided by the team

9. Minimal process artifacts required • Vision • User Requirements Document • Design model • Code • Test plan • with integration in Geant4 system testing • User documentation • README file, web page • Traceability through all the above Improved process documentation in preparation…

10. Peer reviews • Design and code reviews included in the process • We would like to do more… • Limiting factor are time and distance… • Main problem encountered: the reviewers are too nice! • Next reviews will provide a more detailed checklist to guide the reviewers • Spells of fortran++, lack of design, missing or poor documentation, neglection of the software process etc. • Room for improvement in many areas… • …as well as in the rest of Geant4

11. Problems • Since no WG formally exists, some activities escape from any coordination • Some examples “found” in the release without even informing the de facto existing Advanced Examples team • These activities are not subject to the common rigorous software process • Generate problems with software quality, documentation, maintenance, confusion, poor communication • Lack of common vision • Hardly any strategic vision on advanced examples by the Collaboration • A common vision would be beneficial • …not only on advanced examples

12. Maintenance • This is the key problem! • Developing an example is fun • Maintaining an example is NOT fun! • What to do when the original developer(s) quit Geant4? • What to do when the original developers do the maintenance at the last minute, or are “too busy” to do it? • Retire the examples • Somebody else takes over the maintenance • Need a Collaboration/WG policy

13. Interaction with analysis • Simulation goes together with its analysis in real life • Not only common sense, but use cases users submit to us… • Fruitful collaboration with AIDA groups • But there is room for improvement… • Better coordination of releases • Documentation of new features, interface changes etc. in advance • Communication of Geant4 user requirements • Willingness to consider Geant4 requirements

14. In spite of some problems… • …a lot of enthusiasm around advanced examples • A young developers’ team • A wide user community around • A relevant role in Geant4 • Not only user support, but a strategical tool for Geant4 future • A fruitful collaboration across software domains • Simulation, analysis, GRID • Excellent training for many young collaborators to a rigorous software process • The “kernel development” WGs profit of this training exposure

15. Focus for discussion • Maintenance • Relation with analysis • Peer reviews • SPI (integration, process documentation etc.) • New experimental areas to be covered • More detailed introduction by Susanna in the parallel session • Any other topics for discussion? What about recognizing this de facto existing Working Group?