3. Analysis at FCC

FCCAnalyses is a high-level analysis framework developed within the FCC software ecosystem. It provides a convenient interface for performing physics analyses on EDM4hep-based data using ROOT RDataFrame as the underlying event-processing engine.

This chapter introduces FCCAnalyses through a series of practical examples, starting from simple analysis workflows and gradually moving toward more realistic use cases. The final section of this chapter provides a more theoretical introduction to the core tools and data model used throughout FCCAnalyses, including EDM4hep and ROOT RDataFrame, which form the backbone of most workflows.

If you have any problems or questions, you can open an issue on the GitHub repository where these lessons are developed.

Contents:

• 3.1. Getting Started: Higgs Mass Analysis with FCCAnalyses
  • 3.1.1. Part I - Recoil Mass: Analysis and Histograms in a Single Step
  • 3.1.2. Part II - Jet Flavor: Producing a flat ntuple tree before creating histograms and plots
• 3.2. Beyond the Basics: Tracking and Vertexing
  • 3.2.1. Getting the FCCAnalyses
  • 3.2.2. Adding analyzers to the FCCAnalyses
    • 3.2.2.1. Exercise
  • 3.2.3. Reconstruction of the primary vertex and of primary tracks
    • 3.2.3.1. Exercise 1
    • 3.2.3.2. Exercise 2
    • 3.2.3.3. Exercise 3
    • 3.2.3.4. Exercise 4
  • 3.2.4. Reconstruction of displaced vertices in an exclusive decay chain
  • 3.2.5. Analysis of \(\tau \rightarrow 3 \mu\)
    • 3.2.5.1. Exercise 1
    • 3.2.5.2. Exercise 2
    • 3.2.5.3. Exercise 3
    • 3.2.5.4. Exercise 4
    • 3.2.5.5. Exercise 5
    • 3.2.5.6. Exercise 6
• 3.3. Some Useful Info on EDM4hep, Analyzers, and More
  • 3.3.1. EDM4hep in FCCAnalyses
    • 3.3.1.1. EDM4hep event model
    • 3.3.1.2. Structure of EDM4hep Files
  • 3.3.2. Overall organisation of analysis code (C++)
  • 3.3.3. Reading objects from EDM4hep
  • 3.3.4. Association between RecoParticles and MonteCarloParticles
  • 3.3.5. Navigation through the history of the MC particles
  • 3.3.6. Writing a new analyzer
    • 3.3.6.1. C++ string
    • 3.3.6.2. Using ROOT gInterpreter
    • 3.3.6.3. Inside an existing FCCAnalyses module
  • 3.3.7. Writing a new struct
  • 3.3.8. Writing a new module
  • 3.3.9. Writing your own analysis using the case-studies generator
    • 3.3.9.1. Analysis package generation
    • 3.3.9.2. Analysis package exposure to RDF