Minutes of the Geant4 Steering Board Meeting 29 September 2005

Submitted by Anonymous (not verified) on 
 
     
Version 1.4
 
 
Present:
 
CERN: John Apostolakis (JA, chairman), Gabriele Cosmo (GC), Michel Maire (MM), Maria Grazia Pia (MGP), Maya Stavrianakou (MS), Hans-Peter Wellisch (HPW), Gunter Folger (GF), JohnHarvey (JH), Florence Ranjard (FR), Sergey Sadilov (SS), Nikolai Starkov (NS), Vladimir Ivantchenko (VI), Andrea Dell' Acqua (ADA)
 
KEK: Katsuya Amako (KA), Takashi Sasaki (TS)
 
SLAC: Makoto Asai (MA), Dennis Wright (DW), Joseph Perl (JP)
 
TRIUMF: Peter Gumplinger (PG)
 
Ecole Polytechnique: Marc Verderi (MV)
 
Excuses:
 
Aatos Heikkinen, 
 
Minutes: F.Ranjard - v1.0 30 September 2005 
 Revisions: J. Apostolakis 
 
Initial items 
 
     
  • Approval of minutes previous TSB
    No remark. Minutes are approved.
     
  • News from other meetings 
       
    • No CB meeting since the last TSB meeting. 
    • The Collaboration Agreement has been sent for signature in July: SLAC has signed it. CERN is ready to sign. 
    • HPW notified participation in two meetings: GC requested notification of talks on behalf of Geant4 at meetings with a mail to TSB.
       
 
Issues from Technical Forum held on 27.9.05
 
     
  • update of shower parametrization in ATLAS presented: request to discuss potential for further performance improvement (is being followed up by JA). 
  • requirement from BaBar to keep system testing running on Solaris (SLAC to assist with 20% of a FTE) 
  • requirement from LHCb to be able to use a different version of HepMC with a release of Geant4 : accepted - proposed solution to move classes using HepMC to an example. 
  • still a requirement from LHCb: limit the amount of printout to the minimum in production.
 
 
 
Development and Next Release
 
     
  • report on planned migrations
     
       
    • sstream: It can be done in parallel (GC), Category Coordinators can commit. No longer need to compile under gcc 2.95, but should compile on WindowsXP, Visual C++ 7.1 .
       
    • Migration to CLHEP 2.0.x 
         
      • agreed to proceed with evaluation of migration to CLHEP 2.0.2.1; 
      • a requirement is that toolkit and user code must work also with CLHEP 1.9.2.1; 
      • migration done in such a way that users are not forced to use namespace.
         
      •  CLHEP now provide a new header file that enables its users to avoid namespaces for units 
           
        •  Choice rests with Geant4 whether to protect the global namespace or to continue to put units in global namespace. ( This issue is most relevant in case of header files with many units. )
          •  
         
      • Accepted options:
        •  
           
        • Preferred solution: allow only source files to have "using" statements, but not include files 
          •  
        • Agreed/accepted solution: allow each unit that is needed in header file to be defined for this file ( using CLHEP::units::mm; using CLHEP::units::GeV; )
          •  
        • Potential interim solution: allow full 'using CLHEP::units' in header file
          •  
         
      • Choice will remain whether to put units in global namespace in case of header files with many units 
        •  
      • Evaluate the work needed for the migration.
        •  
      • Action (Category coordinators): evaluate first report and migration strategy and provide feedback on issues affecting move during the Geant4 8.0 release cycle.
         
        •  
       
 
     
       
    • Visualisation code migration proposal
       some work is required from other categories but users could also be concerned due to the changes in G4Trajectory (draw method) 
 
     
     
  • Progress with expected development 
       
    • Particle table (no longer static particle definition) : Users need some documentation to use it correctly. Physics lists code use data members which prevent any change by users. 
       
    • Run, Event and Detector response: merge of "envelope " and "region" concept 
    • Geometry and Transport: Overlap detection on construction (placement of volumes) , work is ongoing , prototype planned for October reference tag. 
    • EM physics : energy deposit dependence on step size and cuts is significant for particular materials and setups (HEP: LIC, LHCb reports; medical). The origin was traced to the correlation of angular and lateral distributions in multiple scattering and the choice of step limitation in electron multiple scattering. To address this issue a revised implementation will be made available in the October reference tag. 
         
      • the old behavior will still be available. 
      • Users must be made aware of the changes in physics results and CPU time: results will be independent of step size and cuts (for broader ranges of their value) but at a particular size or cut value CPU time will increase (in several cases, but not all). 
        •  
       
    • User Interface: a prototype Python interface is nearly ready, and will be reported at the Bordeaux workshop.
       
    • Documentation 
         
      • Reorganisation of manuals is ongoing 
        •  
       
    • Advanced Examples
       
         
      • new examples on the way.

         
        •  
       
      •  
     
    •  
 
Collaboration web
 
     
  •  Regarding the move to the new Geant4 Web site scheme , Dennis and Gunter will collaborate to implement the change. A first step is to identify how to redirect key old pages to new locations. 
       
    • Action: GF will prepare recommendation whether/how to redirect old pages to new site. 
      •  
     
  •  Once the redirection issue is resolved (but no later than the week after the Bordeaux meeting) 
       
    • Action: DW to announce to the collaboration the move to new web site design, giving a 2 week period for remarks and suggestions. 
      •  
     
  • GF will make the switch of top page and site, once urgent issues, which have been identified, are addressed. 
  • A new policy was agreed that important information should be available on at least one of the Collaboration web sites and not only from any private site(s). 
  • The possibility to providing mirrors of central collaboration site(s), with copies in different continents or geographic regions was raised. 
  • TSB expressed concerns about: 
       
    • private web pages distributing key issues and about geant4.com site which gives the appearance of a commercial site associated with the Geant4 site - while in fact it is not endorsed or approved by the collaboration. 
      •  
     
       
    • category collaborator lists not maintained up to date.
 

 
Regular items
 
     
  • CHEP 2006: proposal of abstracts should be circulated to the TSB. 
 
Collaboration Agreement
 
     
  • signed by SLAC 
  • CERN is preparing to sign. 
As soon as the number provided by the signing parties reaches 15 FTEs, the agreement will come into force.

 
 
AOB
A TSB meeting is indicated before the G4 workshop to address remaining points on the agenda which were not discussed at this meeting.