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This page provides a very brief overview of the GlueX-specific software used between recording data and publishing results. In time, it should become populated with links to more detailed documentation.

Raw and reconstructed data – halld_recon

  • Raw data is saved in the EVIO file format and processed using programs in halld_recon. (Mark)
  • There are two main databases:
    • Run conditions (e.g. beam current, radiator) are stored in RCDB (web interface)
    • Calibrations and other parameters used in reconstruction/analysis are stored in CCDB (web interface).
    • Hall-D Online Skim System records data for individual raw data files HOSS (e.g. number of events per file, number of each trigger type, ... n.b. only for 2020 and later Run Periods)
  • hd_root is used to analyse EVIO and REST data with plugins for monitoring, Calibrations, and event reconstruction (Mark)
  • REST files are an HDDM format which stores reconstructed physics objects (no detector hit information) (Richard)

Simulated data - halld_sim

  • Simulated data are in HDDM format. (Richard)
  • Event generators generate simulated physics data (particle, momentum, track angle) (Simon & Malte)
  • hdgeant4 models the measurements (detector hits) produced by those tracks (Richard)
  • mcsmear models the detector resolution which makes the measurements less exact. (Richard)
  • MCWrapper runs the above on demand. (Sean)

Reaction channel analysis

  • ReactionFilter plugin is used to find the events corresponding to a particular reaction to make Analysis Trees. The basic ideas and steps are outlined here(Beni)
  • Requests for analysis trees are collected via a webpage, and launched bundled together on the JLab farm. Lists for already existing trees are kept here.

Analysis Tree analysis

  • DSelectors are used to analyze "Analysis Trees" (see reaction filter above) to generate histograms of invariant mass etc. and generate highly reduced output trees for further analysis. Analyze an Analysis Tree(Beni)
  • FSRoot is an alternative to DSelectors that uses flat trees.
  • AmpTools (GitHub, User Guide) is used for partial wave analysis. GlueX specifics are documented here (PRIVATE) (Malte)