Alice-O2 framework

Table of contents

• General information
• FemtoUniverse
• Git
• Notes

Genral information

This repository is dedicated to the O2 software.

Here is the link to the O2 Analysis Framework Documentation: https://aliceo2group.github.io/analysis-framework/.

FemtoUniverse

FemtoUniverse is a part of the O2 framework, the code can be found in the O2Physics/PWGCF folder.

It is used and developed for femtoscopy and angular correlations.

Skimmed data with FemtoUniverse producer

The task femtoUniverseProducerTask.cxx, which can be found in the O2Physics/PWGCF/FemtoUniverse/TableProducer, is used to create smaller data files (to create so-called skimmed data). FemtoUniverse producer from the input file AO2D.root creates a file with the selected information, which is saved in the output file called FemtoAO2D.root. In the FemtoUniverse producer we can choose which particles we want to save. We can save tracks (kaons, pions, protons), V0s, phi and charmed mesons. To save the selected particles you need to run the corresponding process, for example, to save charmed mesons and tracks you need to run the processTrackD0mesonData process.

To run the femtoUniverseProducerTask.cxx locally, you need the following files:

• prod.sh,
• prod-Run3.json.

Note: On my github, they are prepared to save charmed mesons and tracks.

If we already have a file with stored particles. Then we can run the task with the analysis we want to perform (in this case, it is the analysis of angular correlations).

Angular correlations of charmed mesons

The task dedicated to this analysis is femtoUniversePairTaskTrackD0.cxx.

To test the code locally, two files are needed:

• run-D0-task.sh,
• task-config.json.

So far, in the task you can find the following process functions:

• processD0mesons (filling basic plots for D0/D0bar mesons),
• processSideBand (creating D0-D0bar pairs and filling histograms to obtain the angular correlations using side-band method)
• processSameEvent (creating the ΔηΔφ plots for same event)
• processSameEventMC (as above, but with Monte Carlo)
• processMixedEvent (creating the ΔηΔφ plots for same event)
• processMixedEventMC (as previous one, but with Monte Carlo)

Git

Git guide: https://github.com/git-guides

Branches

• git checkout -b new-branch-name -> Use to create a new branch.

  Note: When you create a new branch you are automatically switched to it.

• git branch -vvv -> Use to check which branch you are on.

• git checkout branch-name -> Use to switch to an existing branch.

Keep your branch up to date and solve conflicts

• git fetch upstream
• git rebase upstream/master

Other commands

• git status -> Use to display paths/files that are changed from the current HEAD commit

  For more go here: https://github.com/git-guides/git-status

• git add -> Use to add new and/or changed files from your working directory to the Git staging area

  For more go here: https://github.com/git-guides/git-add