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Getting Help

This tutorial provides an introduction to many aspects of an ATLAS analysis. However, it cannot cover all possible scenarios you may encounter in the course of your analysis work. There are numerous resources that you can use to seek help for any computing difficulties you have.

During the Tutorial

During the tutorial, the tutors are your first point of contact for help. If you are participating in an in-person tutorial, talk to the tutors in the room. If you are doing a remote/asynchronous tutorial, you can ask for help on the Discord server if one is provided; otherwise you can send an email to the tutors at atlas-sw-tutors-organisers@cern.ch. For any questions/issues not directly related to the tutorial material, please keep reading to find the appropriate channel to get help (though you are also welcome to ask some of these in Discord if you wish).

Asking Questions

Don't be shy about asking "beginner" questions, that is the purpose of this tutorial and the various channels provided on this page.

Documentation: ATLAS Twiki Pages

The majority of ATLAS internal information is documented on Twiki pages. Within the Twiki pages, you will find details about technical implementations, analysis and combined performance recommendations, and contact information for conveners and other experts. This tutorial makes references and provides links to many Twiki pages in relevant sections, but a good place to start is the main ATLAS page:

Some of the main pages that might be useful to you are:

Some groups use non-Twiki documentation; these will generally be linked from the Twiki, so the Twiki is almost always a good starting point.

Groups that can offer help

ATLAS has many groups of experts who provide excellent resources and make themselves available to help with any issues you may be facing. Please make use of the group Twiki pages as well as their ATLAS-talk channels and mailing lists. Before asking for help, it can be useful to check the archives on ATLAS-talk.

Analysis Model Group

The Analysis Model Group (AMG) is responsible for developing and overseeing analysis frameworks and tools. This tutorial is under the purview of AMG.

Physics Modeling Group

The Physics Modeling Group (PMG) is responsible for the development and validation of Monte Carlo (MC) simulation of physics processes. The simulation of physics processes that are specific to an analysis are the responsibility of the analyzers or the physics group, but PMG is responsible for giving the final approval for all production requests. Contact information is available on the PMG twiki for experts in all aspects of MC generation and a central mailing list is available for general questions.

Statistics

The Statistics Forum is responsible for all recommendations and support related to statistical analysis. They provide support for numerous commonly used statistical tools and are available to help with any analysis-specific questions you may have.

Trigger Group

The Trigger Group can provide help for all questions related to triggers, especially in the context of analyses.

Distributed Computing

For difficulties with distributed computing (running on the grid, accessing files on the grid, etc), a good first point of contact is the distributed analysis help list:

The Production and Distributed Analysis (PanDA) system is used to process computing jobs on the grid. It is covered in detail in this tutorial.

Rucio is used to transfer data around the grid, and is also covered in this tutorial.

CERN Batch Service

CERN provides access to the HTCondor batch system (replacing the previous LXBatch system). The system's usage will be presented in the tutorial.

Mattermost

Mattermost is a team communication service very similar in functionality to Slack. This is supported at CERN and can be accessed by the Mattermost App or through the CERN Mattermost page. You should have access to the service by default if you have a CERN account.

CERN Mattermost has several "teams" you can join, each of which has multiple channels. A good place for software questions is the atlassoftware team.

CERN Service Portal

The CERN Service Portal is the place to visit for questions and problems with CERN infrastructure and services. These include things like account management, CERNBox, service outages, security, etc. If you're pretty confident that the issue you are facing is not an "ATLAS" issue, but a CERN issue, the service portal is the right place to go:

https://cern.service-now.com/service-portal/

Note that because of the name, Service NOW, you will often hear tickets in this system referred to as SNOW tickets.

What To Include

When contacting the mailing lists please be as detailed as possible. When asking for software help, you will never be accused of providing too much detail.

Include things such as:

  • A minimal example that reproduces the problem
  • Log files
  • Links to grid jobs
  • Exact command(s) used
  • Your source code (via GitLab)
  • Input files

If log files or input files are large, share them via CERNBox.

The CERN Code of Conduct

Please remember, the CERN Code of Conduct applies to all of these communication channels.