geant4

$Id: README,v 1.17 2010-11-08 10:38:44 maire Exp $
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     =========================================================
     Geant4 - an Object-Oriented Toolkit for Simulation in HEP
     =========================================================

                            AnaEx01
                            -------
 This example shows the usage of histogram and tuple manipulations using 
 an AIDA compliant system. All analysis manipulations 
 (attaching an AIDA implementation, histo booking, filling, saving 
 histos in a file, etc...) are located in one class : HistoManager.
 
 The example is an adaptation of examples/novice/N03. It describes a simple 
 sampling calorimeter setup.
	
 1- Detector description
 -----------------------
 
 The calorimeter is a box made of a given number of layers. A layer
 consists of an absorber plate and of a detection gap. The layer is
 replicated.
 	
 Six parameters define the calorimeter :
 	- the material of the absorber,
	- the thickness of an absorber plate,
 	- the material of the detection gap,
 	- the thickness of a  gap,
 	- the number of layers,
 	- the transverse size of the calorimeter (the input face is a square). 
 	
 The default geometry is constructed in DetectorConstruction class,
 but all of the above parameters can be modified interactively via
 the commands defined in the DetectorMessenger class.


	|<----layer 0---------->|<----layer 1---------->|<----layer 2---------->|
	|			|			|			|
	==========================================================================
	||		|	||		|	||		|	||
	||		|	||		|	||		|	||
	||   absorber 	|  gap	||   absorber 	|  gap	||   absorber 	|  gap	||
	||		|	||		|	||		|	||
	||		|	||		|	||		|	||
 beam	||		|	||		|	||		|	||
======>	||		|	||		|	||		|	||
	||		|	||		|	||		|	||
	||		|	||		|	||		|	||
	||		|	||		|	||		|	||
	||		|	||		|	||		|	||
	||    		| 	||    		| 	||    		| 	||
	==========================================================================
	
 	    
 2- An event : PrimaryGeneratorAction
 ------------------------------------
 
 The primary kinematic consists of a single particle which hits the
 calorimeter perpendicular to the input face. The type of the particle
 and its energy are set in the PrimaryGeneratorAction class, and can
 be changed via the G4 build-in commands of ParticleGun class.
 	

 3- Histograms
 ------------- 
 To produce histograms, at least one of the AIDA implementations should be 
 available. See the file InstallAida.txt
    
 AnaEx01 can produce 4 histograms :
  
  histo 1 : total energy deposit in absorber per event
  histo 2 : total energy deposit in gap per event	  
  histo 3 : total track length of charged particles in absorber per event 	
  histo 4 : total track length of charged particles in gap per event 
 
 And 1 Ntuple :
  one raw per event : EnergyAbs EnergyGap TrackLAbs TrackLGap
  
 These histos are booked in HistoManager and filled from EventAction.
 
 One can control the name of the histograms file and its format:
 default name     : AnaEx01
 possible formats : hbook root (default) xml
 
 See HistoManager constructor
    
 Note that, by default, histograms are disabled. To activate them, uncomment
 the flag G4ANALYSIS_USE in GNUmakefile, *before* compilation.
   
 4- OpenScientist
 ----------------

 The file UseOpenScientist.txt gives some indications how to use this system to
 visualize and handle histogram files.