ATLAS Software & Datasets

Centralized ATLAS Tutorial

The ATLAS Analysis Software Group (ASG) maintains a very detailed tutorial for getting started with ATLAS specific analysis software. If you have to analyze ATLAS analysis-level datasets, so-called DAODs (derived analysis object data), then going through the central tutorial is absolutely necessary. This tutorial can be found here.

Downstream Datasets

The defition of “downstream datasets” is relative to a specific task, but usually in an ATLAS analysis the final steps are performed on so-called “flat ntuple” style datasets. These are datasets which are independent of the complex collaboration specific software stack. The tools described in the later sections of this website are perfect for analyzing flat ntuple datasets. The ATLAS DAOD datasets are far from flat (they have a complex structure that is required to maintain flexibility to be used by many collaborators, while flat ntuples are usually fine tuned for a handful of people in an analysis).

If you need to analyze DAODs, the rest of these docs can still be useful for later steps in your work, but the ASG tutorial is your best friend. If you’re analyzing very downstream datasets that are in a plain ROOT ntuple format, then the rest of these docs should definitely be useful (most analyzers generate plain ROOT ntuples from DAODs).