Minutes of 23 March 2020 Meeting of Geant4 Technical Forum Editor: A. Morsch, 23 March 2020 - Starting at 16:00 Introduction ============ + see slides for detail - Geant4 version 10.6 patch01 released February 14h - Next release early December 2020 - Beta release end of June - Feedback on workplan is welcome ! Patch release 10.6-p01 and 2020 work plan - non-physics part ============================================================ + see slides for details Patch release 10.6-p01 and 2020 work plan - EM physics part =========================================================== + see slides for details Patch release 10.6-p01 and 2020 work plan - Hadronic physics part ================================================================= + see slides for details - Clarification S3: G4HadronInelasticDataSet : fixed wrong Gheisha cross section - Does not affect the main reference physics lists - true for 10.6, but could effect 10.5 and earlier, to be investigated Open requirements ================= + see slides for details - Commnent NA62 Geant4 offers a biasing method for forcing collisions (see example GB02). However, after a discussion with Marc, we found out that this only works for neutral particles. Since NA62 uses a K+ beam, a biasing with forced collisions for charged particles would allow for generating samples of useful statistics within a reasonable time to study the rare inelastic interactions in thin material in more detail. **** New Requirements from Experiments ATLAS ===== + see slides for details - In 10.6 tests ATLAS spotted an issue with G4MagInt_Driver having a slightly different implementation than G4IntegrationDriver (already present in 10.4) CMS === + see slides for details - Comparisons of predictions from Geant4 versions 10.4.p03 and 10.6.p01 with test-beam and collision data show agreement within statistical uncertainty Constraining the anti-deuteron nuclear inelastic cross-section with ALICE ========================================================================= + see slides for details - Constraints on sigma_inel(anti d) point at steeper rise at low momentum than implemented by Geant4 - Request: proper treatment of hypertriton in the propagation - Currently treated as a normal nucleus, but from its structure is more like a halo-nucleus - If available, similar study as presented today will be possible for hypertriton in the future