xAOD Samples

Last update: 11 Mar 2024 [History] [Edit]

In this tutorial we are using an example derived xAOD leptoquark signal sample file. For your analysis it is usually necessary that you use a derived xAOD (due to corrections that take place and additional information that is created, such as additional jet collection or other decorations, in going from the primary xAOD to the derived version). In Run 2, a large number of different derivation formats existed, which resulted in significant duplication of data and MC. Moving into Run 3, the majority (estimated to be 80%) of analyses should be using the DAOD_PHYS format. More information about derivations can be found here:

tip At some point, analyses will mostly be requested to move to DAOD_PHYSLITE from DAOD_PHYS. The DAOD_PHYSLITE is designed to reduce the computational requirements for an analysis. Read more about the DAOD_PHYSLITE data format in ATL-SOFT-PROC-2023-029 and the corresponding Physics Briefing.

Tutorial Data

To correctly locate the currently recommended tutorial data, define the environment variable $ALRB_TutorialData which will point to the location of the input data used for the tutorial (this depends on which tutorial and where you are running).

If you are working on lxplus, define it as:

export ALRB_TutorialData=/cvmfs/atlas.cern.ch/repo/tutorials/asg/cern-mar2024

tip If you want to avoid calling this each time you log in for this tutorial, you can put the command in your login script (.bashrc or similar). But be sure to remove it from your login script after the tutorial. It is good practice to avoid setting unneeded environment variables everytime you log in.

This will ensure you are able to locate the data files necessary to complete this tutorial. You either need to run the command directly or, if you added to your .bashrc login script, you should open a new terminal or call:

source $HOME/.bashrc

If you are participating in the ATLAS software tutorial the ALRB_TutorialData variable may be provided to you by the tutorial organizers. However, if you are working from lxplus or on a tier 3 site, the command above will be enough (depending on which shell you are using).

This will ensure you are able to locate the data files necessary to complete this tutorial.