//$Id$

///\file "electromagnetic/TestEm5/.README.txt"
///\brief Example TestEm5 README page

/*! \page ExampleTestEm5 Example TestEm5

 How to study the transmission, absorption and reflection of particles through
 a single, thin or thick, layer of material.
 In particular, the effects of the multiple scattering can be plotted.  
	
\section TestEm5_s1 GEOMETRY DEFINITION
 
 The "absorber" is a box made of a given material.                
 	
 Three parameters define the absorber :
 - the material of the absorber,
 - the thickness of an absorber,
 - the transverse size of the absorber (the input face is a square). 
    
 A volume "World" contains the "absorber". 

 In addition a transverse uniform magnetic field can be applied.
 	
 The default geometry is constructed in DetectorConstruction class, but all the
 parameters can be changed via commands defined in the DetectorMessenger class.
 The parameters of the "World" can be changed, too. However, if World material
 is not set to vacuum, the plots 10->43 below may be not pertinent.
 
\section TestEm5_s2 PHYSICS LIST

 Physics lists are based on modular design. Several modules are instantiated:
 1. Transportation
 2. EM physics
 3. Decays
 4. StepMax - for step limitation

 EM physics builders can be local (eg. in this example) or from G4 kernel
 physics_lists subdirectory.
     
 Local physics builders:	 
 - "local"   standard EM physics with current 'best' options setting
                 these options are explicited in PhysListEmStandard
 - "standardSSM" standard EM physics with alternative single Coulomb
                 scattering model instead of multiple scattering.

 From geant4/source/physics_lists/builders:
 - "emstandard_opt0" recommended standard EM physics for LHC
 - "emstandard_opt1" best CPU performance standard physics for LHC
 - "emstandard_opt2" similar fast simulation
 - "emstandard_opt3" best standard EM options - analog to "local" above
 - "emstandard_opt4" best current advanced EM options standard + lowenergy
 - "emstandardWVI" standard EM physics and WentzelVI multiple scattering
 - "emstandardSS"  standard EM physics and single scattering model
 - "emlivermore"  low-energy EM physics using Livermore data
 - "empenelope"   low-energy EM physics implementing Penelope models
 - "emlowenergy"  low-energy EM physics implementing experimental
                  low-energy models
           
 Physics lists and options can be (re)set with UI commands
    
 Please, notice that options set through G4EmProcessOptions are global, eg
 for all particle types. In G4 builders, it is shown how to set options per
 particle type.

\section TestEm5_s3 AN EVENT : THE PRIMARY GENERATOR
 
 The primary kinematic consists of a single particle which hits the absorber 
 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 G4ParticleGun class (see the macros provided with this example).
	
 In addition one can choose randomly the impact point of the incident particle.
 The interactive command is built in PrimaryGeneratorMessenger class.
 
\section TestEm5_s4 VISUALIZATION
 
 The Visualization Manager is set in the main () (see TestEm5.cc).
 The initialisation of the drawing is done via the commands in vis.mac
 In interactive session:
\verbatim
 PreInit or Idle > /control/execute vis.mac
\endverbatim
 	
 The example has a default view which is a longitudinal view of the detector.
 	
 The tracks are drawn at the end of event, and erased at the end of run.
 Optionally one can choose to draw all particles, only the charged, or none.
 This command is defined in EventActionMessenger class.
 
\section TestEm5_s5 TRACKING
 
 During the tracking, one can keep or not the secondaries : see StackingAction
 class and its Messenger (StackingMessenger).
 One can also limit 'by hand' the step lenght of the particle. As an example,
 this limitation is implemented as a 'full' process : see StepMax class and its
 Messenger. The 'StepMax process' is registered in the Physics List. 
  	
\section TestEm5_s6 DETECTOR RESPONSE
  	
 At the end of a run, from the histogram(s), one can study different
 physics quantities such as :
 - energy deposit in the absorber,
 - energy spectrum of secondaries at creation, 
 - energy spectrum and angle distribution of particles at exit,
 - transmission and backscattering coefficients,
 -  ...
 
\section TestEm5_s7 List of the built-in histograms
        
 The test contains more than 20 built-in 1D histograms, which are managed by
 G4AnalysisManager class and its Messenger. The histos can be individually activated
 with the command :
\verbatim
/analysis/h1/set id nbBins  valMin valMax unit 
\endverbatim
 where unit is the desired unit for the histo (MeV or keV, deg or mrad, etc..)
 (see the macros xxxx.mac).
 
 - 1 :  "energy deposit in absorber"
 - 2 :  "energy of charged secondaries at creation"
 - 3 :  "energy of neutral secondaries at creation"
 - 4 :  "energy of charged at creation (log10(Ekin))"
 - 5 :  "energy of neutral at creation (log10(Ekin))"
 - 6 :  "x_vertex of charged secondaries (all)"
 - 7 :  "x_vertex of charged secondaries (not absorbed)"
 - 10 :  "(transmit, charged) : kinetic energy at exit of world"
 - 11 :  "(transmit, charged) : ener fluence: dE(MeV)/dOmega"      
 - 12 :  "(transmit, charged) : space angle dN/dOmega"
 - 13 :  "(transmit, charged) : projected angle at exit of world"
 - 14 :  "(transmit, charged) : projected position at exit of world"
 - 15 :  "(transmit, charged) : radius at exit of world"   
 - 20 :  "(transmit, neutral) : kinetic energy at exit of world"
 - 21 :  "(transmit, neutral) : ener fluence: dE(MeV)/dOmega"      
 - 22 :  "(transmit, neutral) : space angle dN/dOmega"
 - 23 :  "(transmit, neutral) : projected angle at exit of world"
 - 30 :  "(reflect , charged) : kinetic energy at exit of world"
 - 31 :  "(reflect , charged) : ener fluence: dE(MeV)/dOmega"      
 - 32 :  "(reflect , charged) : space angle dN/dOmega"
 - 33 :  "(reflect , charged) : projected angle at exit of world"
 - 40 :  "(reflect , neutral) : kinetic energy at exit of world"
 - 41 :  "(reflect , neutral) : ener fluence: dE(MeV)/dOmega"      
 - 42 :  "(reflect , neutral) : space angle dN/dOmega"
 - 43 :  "(reflect , neutral) : projected angle at exit of world"

 The histograms can be viewed using ROOT or PAW.
 
 One can control the name of the histograms file with the command:
\verbatim
/analysis/setFileName  name  (default testem5)
\endverbatim
    
 It is possible to choose the format of the histogram file : root (default),
 hbook, xml, csv, by using namespace in HistoManager.hh
     
 It is also possible to print selected histograms on an ascii file:
\verbatim
/analysis/h1/setAscii id
\endverbatim
 All selected histos will be written on a file name.ascii  (default testem5) 
    
\subsection TestEm5_subs1 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
 				
\section TestEm5_s8 GEANT4/GEANT3/DATA COMPARISON

 A Geant4/Geant3/exp. data comparison is given here for a few cases.
 These cases can be classified as follow:
 - e-/e+ incident particles versus protons and others. 
 - 3 energy regimes: low: < 1MeV; medium: 1MeV -> few 10MeV; high: > 100MeV
 
 We indicate here the corresponding macros.
<pre> 
 	      |	low energy   |	medium energy	|  high energy
	--------------------------------------------------------
	      | acosta.mac   |                  |
	e-+   |	berger.mac   |	hanson.mac      |
	      |	hunger.mac   |	kulchi.mac      |
	      | tavola.mac   |			|
	--------------------------------------------------------
	others|	bichsel.mac  | 	vincour.mac	|  shen1.mac shen2.mac
	      | 	     |	gottsch.mac	|  tramu.mac
	--------------------------------------------------------
</pre>
 The relevant part of the GEANT3 code is in the subdirectory geant3 together 
 with the xxxx.dat input files.
	
\section TestEm5_s9 HOW TO START ?
 
 - Execute TestEm5 in 'batch' mode from macro files e.g.
\verbatim
% $(G4INSTALL)/bin/$(G4SYSTEM)/TestEm5   myMacro.mac
\endverbatim
		
 - Execute TestEm5 in 'interactive' mode with visualization e.g.
\verbatim
% $(G4INSTALL)/bin/$(G4SYSTEM)/TestEm5
\endverbatim
Then type your commands, for instance :
\verbatim
Idle> control/execute vis.mac
Idle> run/beamOn 5
....
\endverbatim
 
*/
