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Metadata

Below, you will find the metadata for all the samples, which includes the following:

  • Dataset ID: Unique identifier assigned to each dataset.
  • Physics short: Short name with information regarding the content of the dataset.
  • CoM Energy (GeV): Center of mass energy.
  • Cross section (pb): A cross section represents the probability of a particular interaction occurring, measured in picobarns (pb). It is a fundamental parameter that helps understanding the likelihood of specific particle interactions under given conditions. The cross section is usually what is returned by the generator - a user needs to multiply by the filter efficiency and k-factor (see below) to get a complete sample weight.
  • Filter efficiency: Measure of the effectiveness of the selection criteria applied to the data. It indicates the fraction of events that pass the filters applied during the data processing stages.
  • K-factor: Multiplicative correction factor used to account for higher-order effects in theoretical calculations. It adjusts the leading-order theoretical predictions to better match the observed data by incorporating next-to-leading order (NLO) or next-to-next-to-leading order (NNLO) corrections.
  • Number of Events: Total count of events in the released HEPMC dataset.
  • Generated events: Total count of generated events available internally. If you require more events and we have them available, please get in touch.
  • Generator used: Specifies the simulation software used to generate the data. Information about the generators can be found in the Simulation Tools section.
  • Generator tune: The parameter settings used in the event generation, in particular for fragmentation and hadronization.
  • PDF: The parton distribution function used for the event generation.
  • Keywords: Terms or phrases associated with the dataset that help to find specific datasets.
  • Process Description: Brief description of the physics process being studied. For instance, "H->γγ\gamma\gamma" denotes the Higgs boson decaying into two photons.
  • Release: Version of the ATLAS software (usually the AthGeneration release version) used to generate the events.
  • Filters: A list of any filters applied during event generation (e.g. requiring at least two leptons.)
  • Job options: Link to the specific code or configuration files used to generate the sample.

API for Metadata Access​

We have developed the atlasopenmagic python package for convenient access to metadata for the available samples. Simply setup your preferred release and you can request all the metadata available in the table below from your python notebook or modules. The package also provides helper functions for file access. Because of the size of the metadata, this package is strongly recommended for the event generation open data.