Users Guide for AliRoot

Content

1. How to run AliRoot
2. AliRoot classes

1. How to run AliRoot

To execute the Alice detector simulation program.

• Type: $ aliroot
  this starts AliRoot in interactive mode by default after few seconds the root prompt apears
  you can now start a AliRoot interactive session by either creating the standard menu
• Type: root[0] .x menu.C
  or directly
• Type: root[1] gAlice->Run()
  or
• Type: root[1] gAlice->RunLego()
  
  to divert the long output generated by the AliRoot initialisation phase to an eg. AliRoot.log file
• Type: root[3] .x menu.C > AliRoot.log
  or
• Type: root[4] gAlice->Run(); > AliRoot.log

The time for the initialisation phase of AliRoot is typicaly 30 seconds.

By default the macro menu.C invokes AliRun::Init with the configuration file Config.C.

When the initialisation is finished the root prompt apears again.
You also get back the Root control bar menu.

You can now select options from the bar menu.

• Run
  to generate an event with the number of tracks and the configuration as specified in Config.C
  
  
• RunLego
  to generate the standard lego plots for radiation and absorption length. By default the granularity is 60 rays in theta and 60 rays in phi.
  To view the results when this command is finished type:
  
  root[0] .x lego.C
  
  to change the parameters if you do not want to run with the default ones type:
  
  root[3] gAlice->RunLego (your list of parameters)
  
  see AliRun::RunLego for details
  
  
• Top, Front, Side view
  to generate the corresponding cut view of Alice detector.
  note that it takes a long time to execute a cut view typicaly of the order of about 30 sec.
  
  
• Menu Trees
  this shows a new menu from which you can draw the geometry tree for most of Alice detectors.
  double-clicking on an Alice detector generates its specifications.
  
  
• Menu Pictures
  this shows a new menu from which you can draw the major Alice detectors in shade mode.
  
  
• Other Options
  allow to switch ON/OFF various drawing modes.

For more details on the functionality see the documentation of AliRun and TGeant3 classes

A global varial gAlice can be used to invoke the AliRun class functions.
A global varial gMC can be used to invoke the TGeant3 class functions.

Note that several TGeant3 functions are also available by clicking with the right button on a canvas while in the AliRoot session.

To quit AliRoot

• Type: root[3] .q