Minutes of 29 March 2019 Meeting of Geant4 Technical Forum
Editor: A. Morsch, 30 March 2019
- Starting at 16:00

General introduction and prospects
==================================
+ see slides for details
- Geant4 10.4-patch03 has been released on February 12
- Comments on the 2019 workplan are appreciated 
- Next major release foreseen December 6 2019 (beta release July 28, 2019)

Summary of 2019 work plan - non–physics part
============================================
+ see slides for details
- S04 The Hypernews fora will be moved to Discourse. The fallback solution (only in case migration does not preserve links) is to freeze the Hypernews pages and have 
a fresh start with Discourse.

Summary of 2019 work plan - EM physics part
===========================================
+ see slides for details
- S10 Also some progress on Micro&Nano dosimetry models for Silicon
- S11 Clarification: author names are preserved in history when extracting patches from GitHub and injecting into GitLab.

Summary of 2019 work plan - hadronic physics part
=================================================
+ see slides for details
- S09 Development and validation of the infrastructure for studying sensitivity of the MC predictions to the variations of the
model parameters. Fermilab: The plan is to publish a paper within a few months as a first stage. Many parameters have not yet been exploited. 
- S04 INCL++: work on solution for ALICE to use this model for inner tracker only.
- No experiment feedback on Birk's Quenching proposal (see G4 TF 2019-01) yet.



Status of open requirements
===========================
+ see slides for details
+ New Requirements
- no new requirements
+ Open Requirements
- 4701: More realistic matrix element for decays tau->nu+hadrons: Will contact requester to see if external decayer would be a satisfactory solution (ok for ATLAS).
- 4702: Inclusion of gamma polarisation effects in high-energy EM models. Difficult but requested by ATLAS and CMS. In the workplan, but can take several years.
- 4703: Improved light nucleon production in FTFP_BERT (to provide similar performance to FTFP_INCLXX). In 2019 workplan.
- 4002 Reweightable uncertainties for systematic uncertainty estimation: A note is circulated among the developers, will be made available soon. To be presented at ACAT'19
+ Closed
- No Recently closed requirements.



**** New Requirements from Experiments

ATLAS
=====
+ see slides for details
- S06 Several explanations why exception mainly seen with muons: can reach critical region, smaller stepsize, ...
- S07 Suggestion to split Polycone along z-axis to gain performance. 
- S08 Sharp peak (line) in spectrum caused by photo effect produced by photons from positron annihilation.
- S17 Problem is in Athena not in G4
- S18 Improving the robustness of commands executed via G4UIManager: Makoto will meet with ATLAS experts to go through the list of commands.


CMS
===
+ no slides
- CMS would like to thank the Geant4 team for providing the patch 10.4p03, which is now integrated into CMSSW to be used for legacy MC production for run-2. 
- Production in multi-threading mode is going well. 
- CMS produced >20 B events with Geant4 10.2p02 and >10B events with 10.4