geant4

$Id: README 73919 2013-09-17 07:38:47Z gcosmo $
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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 
 G4Analysis system. All analysis manipulations 
 (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- Action Initialization
 ------------------------------------

   A newly introduced class, ActionInitialization, 
   instantiates and registers to Geant4 kernel all user action classes 
   which are defined thread-local and a run action class
   which is defined both thread-local and global.
   
   The thread-local action classes are defined in 
     ActionInitialization::Build() 
   and  the global run action class is defined in 
     ActionInitialization::BuildForMaster().
   Note that ActionInitialization::Build() is also used to 
   instatiate user action clasess in sequential mode.

 3- 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.
 	

 4- Histograms
 ------------- 

 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 2 Ntuples :
 - ntuple 1:
   - one row per event : EnergyAbs EnergyGap
 - ntuple 1:
   - one row per event : TrackLAbs TrackLGap
  
 These histos and ntuples are booked in HistoManager and filled from 
 EventAction.
 
 One can control the name of the histograms file and its format:
 default name     : AnaEx01   
 The format of the histogram file can be : root (default),
 hbook, xml, csv. Include correct g4nnn.hh in HistoManager.hh 
 
 Using hbook format
 ------------------
 
 Need a special treatement : the Cern Library must be installed and the
 environment variable CERNLIB correctly set. Then, *before* compiling,
 activate G4_USE_HBOOK in GNUmakefile and  g4hbook.hh in HistoManager.hh