Displaying the invisible

Events produced at the LHC are complicated, and visualization requires both expertise and some basic knowledge about how particles interact with the detector. Several programs were developed by the ATLAS collaboration, in 2D or 3D, adapted for specific tasks. The one that we are using is called "Virtual Point 1" (VP1), point 1 being the name of the experimental area of ATLAS. On real data one usually displays energy deposits and reconstructed trajectories, plus some of the detector elements to guide the eye. For simulation jobs like yours we have :

"Truth" = the original physics content of the event, that is to say the directions and ideal trajectories of the particles created in the collision. This view is - obviously - not present in real data.

"Hits" = the energy deposited by particles while crossing the detector sensitive elements

The image below is an example. It was made using an event produced by one of the volunteers, merged and stored by the production system on the CERN computing center and picked up by an ATLAS physicist.  One of our goals is to provide these views, it requires technical development [sept 2014, work in progress]. Meanwhile, you can explore the links below. 


Links :


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