Low Energy Electromagnetic Physics

1. Low Energy Electromagnetic Physics Maria Grazia Pia INFN Genova on behalf of the Low Energy Electromagnetic WG Geant4 Workshop Genova, 2-6 July 2001 http://www.ge.infn.it/geant4/lowE/

2. A growing Working Group • 2 collaborators working on LowE e.m. physics in January 1999 • 9 members at the time of the creation of the WG • 3 of the initial members lost • including holder of full time ESA contract • >50 members now • Contacts in progress with new people interested to join 2000 2001

3. How we operate Goal-directed project management Rigorous approach to software engineering High dynamism and creativity Characterized by • Regular Working Group meetings • Emphasis on training of all group members • Promotion of cross-WG activities • Close relationship with user communities • Active strategy of talks and publications • for promotion of Geant4 and our own products • as an incentive and reward for group members Physics Applications Wide spectrum of development: Team Collaboration Outreach

4. Objectives and Projects 2000 • Documented in public planning document every year • Achievements documented to the Geant4 Collaboration 2001

5. Physics developments • Before the creation of the WG • First implementation of e/photon models based on LLNL libraries (250 eV - 100 GeV)) • First implementation of models for hadrons and ions • Since the creation of the WG • New model for positive charged hadrons (Ziegler 1985) • Improvements on straggling (hadrons and ions) • Dynamic dependence on effective charge in the range calculation • Improvements in the validity range of d ray production • New models for ion energy loss fluctuations • New model for negative charged hadrons (Barkas effect) • New model for polarised Compton • Other physics extensions in progress • Future • Other polarised processes • New model for Compton, Photoelectric • Positrons • Penelope-like models Compton Photoelelctric Rayleigh GammaConversion eIonisation Bremsstrahlung hIonisation PolarisedCompton To learn more: http://www.ge.infn.it/geant4/lowE

6. Huge effort invested into SPI started from level 1 (CMM) chaotic, left to heroic improvisation Current status public URD full traceability through UR/OOD/implementation/test in CVS repository testing suite and testing process public documentation of procedures … A sample of the improvements: establishment (1999) and management of User Requirements Document establishment and documentation of procedures design before coding designs and testing under configuration management separation of examples from tests identification of tasks and responsibilities traceability process ...too long to list all of them Software Process A rigorous approach to software engineering

7. Suite of unit tests 3 system tests Suite of physics tests (in progress with publications) Regression testing Physics validation Testing requirements Testing procedures Testing integrated with development Testing Posted on the WG web site Validation Comparison with experimental data At various levels: details of physics models and global features

8. Results This is small sample of comparisons with experimental data Based on EPDL97, EEDL and EADL evaluated data libraries e, down to 250 eV (EGS4, ITS to 1 keV, Geant3 to 10 keV) Barkas effect: models for antiprotons Low energy hadrons and ions models based on Ziegler and ICRU data and parameterisations

9. Collaboration with user groups in testing Pixel ionisation chamber Relative dose in water •  Independent validation of physics models and implementation Some examples INFN Torino Photon attenuation coefficient in water LIP & Portuguese Oncological Institute Italian National Institute for Cancer Research

10. UR Design Implementation Unit test System test 1.1 LowE.mdl e/photon G4LowEnergyBremsstrahlung G4LowEnergyIonisation G4LowEnergyCompton G4LowEnergyPhotoelectric G4LowEnergyRayleigh G4LowEnergyGammaConversion G4LowEnergyGammaConversionTest G4BremsstrahlungTest G4IonisationTest G4ComptonTest G4Photoelectric G4RayleighTest Test14 1.2 Future Future Future Future 1.3 Future Future Future Future 1.4 Future Future Future Future A.1 LowE.mdl e/photon See 1.1 See 1.1 Test14 A.2 LowE.mdl e/photon See 1.1 See 1.1 Test14 A.3 LowE.mdl e/photon See 1.1 Not available yet Test14 A.4 LowE.mdl e/photon Future Future Future Example of traceability map

11. Documentation User Documentation • Included LowE documentation in Application Developer Guide • Expanded LowE documentation in Physics Reference Manual • Added LowE documentation in Toolkit Developer Guide • Full coverage of all LowE classes in Software Reference Manual Web site http://www.ge.infn.it/geant4/lowE/ • Internal documentation • procedures • URD • design documents • tests • traceability map All regularly updated

13. Advanced examples • Three advanced examples developed by the LowE WG • X-ray telescope • g-ray telescope • brachytherapy • released in December 2000 (first Geant4 advanced examples) • Full scale applications showing physics setting guidelines and advanced interactive facilities in real-life set-ups • More in progress • X-ray fluorescence and PIXE • underground physics and radiation environment • IORT?

14. The user community A user a day keeps the doctor away • The WG promotes close contacts with its users • Large user community, in expansion • excellent relationships with our users • users often contact us directly • the promotion through conferences, seminars, and web pages plays a fundamental role in the contacts with user communities • URD created, maintained and regularly updated • Fruitful collaboration with users on testing

15. Technology transfer • Hospitals • Italian National Institute for Cancer Research • AIRCC • Hospital of Savona • University Hospital of Montreal • Massachussets General Hospital • Coimbra Delegation of Portuguese Oncology Institute • Frederic Joliot Hospital • ... • Companies • From General Electric to RXTEC... Asked the CB for guidelines twice (email to CB chairman + formal memo) No response Strategically important for political and financial implications

16. Presentations 2000-2001 2000 • CHEP 2000 (2) Padova, February • ESA-CERN Workshop on Fundamental Physics CERN, April • PTCOG WorkshopUppsala, April • ICCR Heidelberg, May • Workshop on Space Radiation Research Arona, May • ESTRO CongressIstanbul, September • Calor 2000 Annecy, October • MC 2000 (3) Lisbon, October • AIRO Pisa, October • Spacecraft Charging Technology Conference ESTEC, May • ESTRO Congress Stresa, June • AIFM Congress Brescia, June • Round Table on Monte Carlo methods for space applications (7) ESTEC, June • CHEP 2001 (4 accepted) Bejing, September Seminars (Bologna, DESY, Frascati, Genova, Roma, Stockholm, Udine…) 2001 + several general Geant4 & applications talks by WG members

17. Activities in progress • Completion of the validation of existing implementations • Started with the creation of the WG • Series of polarised LowE processes • Alternative models (Compton, Photoelectric?) • Extension of fluorescence to hadron processes Plan for next release to be discussed in parallel session tomorrow • Design iteration in energy loss domain • Meant to be general • In collaboration with standard EM • Other design iterations foreseen • Data access • Fluorescence • Fine grained models • Will keep us busy for several months • Design iteration + re-implementation + testing

18. Our most time-consuming activities • Getting funds for the group • Lack of commitment from funding parties • Daily struggle to get support even for key activities and developers • Several bright, enthusiastic young collaborators: what future for them? • Dealing with “conservative attitudes” • Non-HEP applications • High dynamism of the WG • Rigorous software engineering • Split of EM groups • … • Management • Necessary service to the group to keep a high quality level of the activity • Significant workload (WG + user communities)

19. Sources of concern • 12 page long URD • Still growing • Approximately 50% of current URD still to be implemented • Human resources • Several “nominal collaborators” • Lack of dedicate people in e/photon domain • Subtraction of key developers by collaborating experiments • Contribution to management from a key party in the WG decreased substantially since last Fall • Typical pattern as in other parties: contribution to Geant4 core development/maintenance is perceived as 2nd priority • Degradation of the software process in the WG • Difficult to get resources for assessment, problem investigation, testing etc. • People more attracted to “fancy” activities (design iteration, new models…) • Education to take milestones seriously

20. A way to improve? • Adequate funds • Perspectives for young collaborators • Focus on concrete achievements of the WG • Support dynamic Working Groups • rather than frustrating them… • Take Geant4 as a high priority commitment

21. Summary • New physics domain in Geant4 • A wealth of new physics models • New fields of application • Wide interest in the user community • A rigorous approach to software engineering • Many results of application A highly dynamic Working Group