EventDisplays

This page details past and present event displays and a geometry display. Sophie Middleton is co-ordinating the current Event Display effort, there are several forms of Event Display currently usable, each is described below:

Geometry Browser

Example of Geometry Viewer.

This system displays the geometry built as part of the geant model of the detector. It does not display events. It has options for cutaways, as seen in the example. It also has the option to make some volumes transparent.

TEveEventDisplay

Example of TEveEventDisplay along with GUI.

Example of PS and TS in TEveEventDisplay along with MCTrajectory (red).

A detailed TEve based display specialized for Mu2e is available, details are found here: [1]. Development began in 2020 and the display is now at an advanced stage, for more information, or to contribute, contact Sophie Middleton who is coordinating the current Event Display effort.

Eve-7 Event Display

Eve-7 is an upgrade to the well-known TEve ROOT-based Event Display. An Eve-7 based Event Display specifically for Mu2e is available, details are found here: [2]. Development began in 2021, for more information, or to contribute, contact Sophie Middleton who is coordinating the current Event Display effort.

EventDisplay

Example of the EventDisplay display.

A display system from Ralf Ehrlich. Run from a module:

mu2e -c EventDisplay/fcl/EventDisplay.fcl -s ..

Controls are in the display and quite intuitive. See also doc-7905 and doc-2371

Stntuple 2-D

Example of the Stntuple 2-D display.

The Stntuple ntuple package includes also a module named MuHitDisplay that provides an interactive 2D event display. By default, the module pops up a canvas with the Tracker X-Y and calorimeter views where are displayed:

• the reconstructed straw hits: black crosses
• the calorimeter clusters: red/magenta circles (red for those on the disk closer to the tracker) where the size is proportional to the reconstructed energy
• reconstructed tracks: blu line

In addition to that, the module prints put the information of the reconstructed tracks.

An additional controller canvas allows to exploit additional views of the detectors:

• Tracker: XY transverse and R-Z longitudinal
• Calorimeter XY
• Cosmic Ray Veto

The calorimeter and the tracker views allow the user to select a specific "Time Cluster" that was reconstructed in the event to seed the track search.

Tracker XY and RZ views

Example of tracker XY view.

Example of tracker RZ view.

The two sets of event projection for the tracker (X-Y and R-Z) provide a complete representation of the reconstructed tracks within a given event. Both canvas allow to zoom specific region inside the canvas. The RZ view include also

Calorimeter XY view

Example of calorimeter XY view.

The calorimeter XY view includes both disks. Each crystal is colored with a red-yellow proportional to the energy reconstructed. The right button of the cursor allows to inspect the crystal-hit information and have them printed in the Terminal.

Navigate inside the event

Example of printout.

This event display allows to inspect all the collection of reconstructed objects given in the Event. MuHitDisplay is run in interpreted mode within ROOT. To print all the informations we need we use the Class Stntuple/mod/TAnaDump.cc . An example of working flow follows:

• d=TAnaDump::Instance(): this command instantiate a pointer to a TAnaDump object
• d->print...: now the user is ready to print out all the collection he wants! The only arguments necessary to use the print... functions are the name of the module instances.

Stntuple 2-D

To run this event display the user needs to add the instance of the MuHitDisplay in the fcl file in the physics.filters block and execute it in the end of the trigger_path. On the Stntuple/fcl/prolog.fcl an example of MuHitDisplay instance block is available.

This package is maintained by P. Murat and G. Pezzullo. From Pasha Murat and Giani Pezzullo as part of the Stntuple ntuple package. Good for detailed examination of tracks and hits. See also doc-13916.

Old TEve Displays

Example of an TEve display.

Pasha Murat has a working geometry display based on gdml and the Stntuple package. Stntuple directions

Pasha Murat is also working on a display for art file based on TEve package (2017).

geant4 qt Event Display

Example of a geant4 qt display.

Best document is a Krzysztof Genser's talk here: doc 3680.

This rather powerful tool is setup to mainly show the details of geometry and possibly tracks of one event, but not any reconstructed quantities.

You must a build a personal version of Offline, and use the g4vis=qt g4mt=off trigger=off buildopts settings:
./buildopts --g4vis=qt --g4mt=off --trigger=off