Ad-hoc : Thursday, March 6, 2025 9:00 am EDT

Participants: Zhongling Ji, Weizhi Xiong, Zhiwen Zhao, Chao Peng

We discussed the plan to implement ACTS tracking for the new SoLID simulation based on DD4Hep

• Milestones:
  • 1) Signal level ACTS tracking (single electron with SIDIS configuration) and comparison with the GEMC results
  • 2) Realistic ACTS tracking (signal + background for SIDIS/PVDIS configuration) and comparison with the GEMC results

• To achieve the first milestone (SIDIS signal level tracking), the expected steps are:
  • i) Verify the geometries for sides tracking
    • dd4hep: https://github.com/JeffersonLab/solid_dd4hep/blob/main/compact/GEM_sidis.xml
    • gemc: https://github.com/JeffersonLab/solid_gemc/blob/master/geometry/gem_moved/solid_SIDIS_gem_geometry.pl
  • ii) Implement the ACTS tracking geometry in the solid_dd4hep repository and run single electron simulations
    • ACTS dd4hep plugin: https://acts.web.cern.ch/ACTS/latest/doc/group__DD4hepPlugins.html
  • iii) Use the existing algorithms in eicrecon for digitization (add resolution smearing and efficiency) and track seeding/finding/fitting
    • ACTS tracking factories in EICRecon: https://github.com/eic/EICrecon/tree/main/src/global/tracking

Contact Shujie Li (shujieli@lbl.gov) for any technical questions regarding steps ii and iii.

• We also discussed the possible ways for the second milestone (background merging and realistic tracking), and they are:
  • a) Use Weizhi's code with necessary modifications as a middleware between simulation and reconstruction
    • This may require significantly less effort and can serve as a short-term solution.
  • b) Use EICRecon and implement the background merging
    • One possible long-term solution but need to explore
  • c) Use DDDigi and implement the background merging
    • The other possible long-term solution and also need to explore