Analysis and Visualization Tools

Juraj Smieško (CERN)

CERN

25 March 2026

FCC PED PS&C Groups

Group definitions during the Reference Design Phase of the FCC project

Organizational structure during the Reference Design Phase of the FCC project

E-groups based mailing lists
- FCC-PED-SoftwareAndComputing-Analysis (also for Visualization)
- FCC-PED-SoftwareAndComputing-MCProduction
- FCC-PED-PhysicsGroup-MCGenerators
- FCC-PED-SoftwareAndComputing-Generators (includes FCC-PED-PhysicsGroup-MCGenerators)
- FCC-PED-SoftwareAndComputing-Resource
FCC Software Forum
- Fit for majority of questions, excellent for posterity
fccsw Mattermost channel
- For quick questions when stuck, a temporary bug report, resource availability, …

Lead the maintenance and development of the FCC analysis software ecosystem by exploring, validating, and integrating new technologies to enhance efficiency, functionality and user-friendliness
- This includes, but is not limited to, utilities for machine learning, statistical combination, kinematic fitting, vertex fitting, ...
Develop mechanisms integrated in Key4hep to produce samples independent of the data model and easy to analyze
- In close contact with other parties (Physics Performance, Detector Concept, MC Production ...), define the content of these samples for the various FCC applications
- Support or perform the implementation of the producers and ensure they are included in the central workflows
Ensure that benchmark analyses (to be defined with the Physics work package) are centrally maintained and ready to run with various detector configurations
Provide user support regarding analysis and visualization tools
Write a comprehensive documentation for all processes, tasks, and systems under their responsibility

FCCAnalyses is a primary tool for the analysis at FCC
podio allows writing an analysis in C++ and Python
RDataFrame in C++ w/wo analyzers from FCCAnalyses
Coffea — awkward-arrays based columnar analysis framework
Julia: high-level, general-purpose dynamic programming language
- Reading of the EDM4hep handled by the EDM4hep.jl package
FLARE — Workflow manager based on b2luigi
FCC Physics Events — dataset metadata catalogue
FCC{ee,hh}PhysicsPerformance — analysis catalogues
CMS Combine (in a container)

Focus on the flagship analyses important for the benchmarking of the detector designs
- Revive FCC{ee,hh}PhysicsPerformance repositories to also host benchmark analyses
  - FCCeePhysicsPerformance → FCCeePhysicsStudies
Expand distributed computing options
- Allow running on GRID, Slurm or other distributed platforms
- Either from within FCCAnalyses or from outside FCCAnalyses (FLARE, law, …)
Better ML support
- Streamline current implementation
- Investigate/adopt ROOT solutions e.g. TMVA SOFIE
- Join the developments in Key4hep
Work on overcoming software ecosystem silos
- Key4hep, PyHEP, DiracOS, Rucio, …
- Streamline NTuple production mechanism
- Improve the performance of the podio::DataSource
- Invest time in tooling/approaches which can bridge the gap

Make FCCAnalyses more robust and capable
- Overhaul the analyzers to support EDM4Hep objects (normal and decayed), ROOT vectors, std::vectors
- Merge staged and histmaker styles together
- Bring Combine to the Key4hep stack
- Revive the plotting capabilities
- Support web based execution environments, e.g. SWAN
Keep up with the improvements in ROOT
- Support processing of RNTuple files
- ROOT's "R" classes
Utilize GPU resources through a specialized analyzers
Develop robust APIs for dataset metadata retrieval
Investigate and benchmark running of FCCAnalyses on non-CERN based computing resources
- Datasets available locally or using Xrootd
Improve handling of metadata between analysis stages, support multiple event weights
Clean up the authorship and referencing

Ensure that adequate visualization tools covering the needs of different purposes are available
- The different purposes include: development and debugging of geometries and simulations, development and debugging of reconstruction algorithms, outreach
Provide user support regarding analysis and visualization tools
Write a comprehensive documentation for all processes, tasks, and systems under their responsibility

Phoenix@FCC
- Developed under HSF, several detectors participating
- Primarily targeted towards outreach, even has VR/AR capabilities
- Web based, convoluted development / packaging
eedE
- Event data explorer
- Web based, Pixi.js as a rendering engine
Pandora Monitoring
- Traditional ROOT based application
- Heavily tied to Pandora
k4CEDViewer
- Fresh port of CED Viewer form iLCSoft
- Traditional application

JSROOT
- Part of the ROOT project
- Primarily visualizes histograms
- Can also visualize detector geometries
- Web based
Geant4 Qt visualization
- Well established tool for Geant4
- Traditional Qt based application
Other specialized tools …
- calodisplay — ALLEGRO event display
- FCCAnalyses — analysis graph generation

No single tool for debugging and development of simulation, reconstruction (and analysis)
- Support the usage and develop / contribute to development of existing tools
- Avoid implementing specialized tools targeting specific sub-detector or use cases
Join the geometry converter efforts in Sim/Reco
- ROOT to glTF conversion rudimentary
- pyg4ometry seems promising
HSF Visualization not active anymore
Investigate where the interoperability of the OS graphics stacks can be improved
- Wayland replacing Xorg
- Xorg/OpenGL windows on MacOS