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    =========================================================
    Geant4 - an Object-Oriented Toolkit for Simulation in HEP
    =========================================================

                              rdecay02
                              --------

  Rdecay02 is created to show how to use the G4RadioactiveDecay process to 
  simulate the decays of radioactive isotopes as well as the induced
  radioactivity resulted from nuclear interactions. 

  In this example a simple geometry consists of a cylindric target placed 
  in the centre of a tube detector. Various primary event generation and 
  tallying options are available.

  1. GEOMETRY

    The world is filled with "Air" and there are two components in it:	     
 
    - Target:  A cylinder placed at the origin along the z-axis. The default 
      size of the cylinder is 0.5 cm radius and 1 cm length, and its default 
      material is "CsI".
		  
    - Detector: A tube centered at the origin along the z-axis, with inner 
      radius matching the radius of the target. The default thickness of the 
      tube is 2 cm and it is 5 cm long. The default material is "Germanium".

    The user can change the target/detector size and material, using the 
    commands in the directory  /rdecay02/det

  2. PHYSICS

    The following physics processes are included by default:

     - Standard electromagnetic
     - Decay
     - Radioactive Decay
         By default radioactive decay is applied through out the geometry.
	 The user can limit it to just the target by commands :
	        /grdm/noVolumes
	        /grdm/selectVolume Target

     - Hadronic processes

  3. AN EVENT: THE PRIMARY GENERATOR
  
    The primary kinematic is a single particle or ion shooted at the 
    centre of the target. The type of the particle and its energy are set in 
    PrimaryGeneratorAction, and can be changed via the G4 build-in commands of
    ParticleGun class (see the macros provided with this example).
    Default is Ne24, at rest.

  4. DETECTOR RESPONSE

    The relevant informations are collected in TrackingAction or 
    SteppingAction. These include:

    - Emission particles in the RadioactiveDecay process: 
        particle PDGcode,
        particle kinetic energy,
	particle creation time,
        particle weight.

	Note: the residual nuclei is not considered as an emitted particle.

    - Radio-Isotopes. All the radioactive isotopes produced in the simulation: 
        isotope  PDGcode,
        isotope  creation time,
        isotope  weight.
 
    - Energy depositions in the target and detector by prodicts of the 
      RadioactiveDecay process: 
        energy depostion (positive value for target and negative for detector), 
        time,
        weight.
  

  5. HISTOGRAMS

   The test contains 7 built-in 1D histograms, which are managed by
   G4AnalysisManager and its Messenger. The histos can be individually 
   activated with the command :
   /analysis/h1/set id nbBins  valMin valMax unit 
   where unit is the desired unit for the histo (MeV or keV, etc..)
   (see the macros xxxx.mac).
 
	histogram 0: The Pulse Height Spectrum (PHS) of the target.
	histogram 1: The PHS of the detector.
	histogram 2: The combined PHS of the target and detector.
	histogram 3: The anti-coincidece PHS of the target.
	histogram 4: The anti-coincidece PHS of the detector.
	histogram 5: The coincidece PHS between the target and detector.
	histogram 6: The emitted particle energy spectrum.
	
   It is assumed the detector and target pulses both have an integration time 
   of 1 microsecond, and the gate is 2 microsecond for the coincidence spectrum.
   The target and detctor have a threshold of 10 keV in the anti-/coincidence 
   modes.

   Initially, all histograms but histogram 6 are inactive.  They can all be turned on 
   with the command

      /analysis/h1/setActivationToAll true

   or specific histograms can be turned on with the command

      /analysis/h1/setActivation i true 

   where i is the histogram index (0,... n).  
   To turn off, set the final argument to false

   
   HistoManager includes also 4 ntuples whose contents are described in the above paragraphe
  (detector response) 
  The ntuples can be activated with the command /analysis/ntuple/setActivation
           
   One can control the name of the analysis file with the command:
   /analysis/setFileName  name  (default rdecay02)
   
   It is possible to choose the format of the histogram file : root (default),
   xml, csv, by using namespace in HistoManager.hh
       
   It is also possible to print selected histograms on an ascii file:
   /analysis/h1/setAscii id
   All selected histos will be written on a file name.ascii (default rdecay02)
   
 6. VISUALIZATION
 
   The Visualization Manager is set in the main().
   The initialisation of the drawing is done via the commands
   /vis/... in the macro vis.mac. To get visualisation:
   > /control/execute vis.mac
 	
   The tracks are drawn at the end of event, and erased at the end of run.
      
   gamma green   
   neutron yellow
   negative particles (e-, ...) red
   positive particles (e+, ions, ...) blue
 	
 7. HOW TO START ?
 
   Execute rdecay02 in 'batch' mode from macro files :
 	% rdecay02   run1.mac
 		
   Execute rdecay02 in 'interactive mode' with visualization :
 	% rdecay02
	Idle> control/execute vis.mac
 	....
 	Idle> type your commands
 	....
 	Idle> exit
	
 8. FURTHER EXAMPLES

   There are a number of g4mac files in the ./macros subdirectory, to show 
   the features of the G4RadioactiveDecay process. Most of them will lead to 
   the creation of an root file in the same name of the macro file.

   u238c.mac: shows the decays of the U238 chain in analogue MC mode.

   th234c-b.mac: shows the decays of Th234 in variance reduction MC mode. 
      All its secondaies in along the decay chains are generated. The default 
      source profile and decay biasing schemes are used to determine the decay 
      times and weights of the secondaries.

   proton.mac: simulation of 1 GeV protons incident on a lead target. 
      The decays of the radio-siotopes created in the proton-lead interactions 
      are simulated with RadioactiveDecay in analogue MC mode.   

   proton-beam.mac: same as proton.mac, but the decays of the radio-siotopes 
      created in the proton-lead interactions are simulated with 
      RadioactiveDecay in variance reduction MC mode. The isotopes and those 
      along the decay chains are forced to decay in the time windows specified 
      by the user in file measures.data, and the weights of the decay products 
      are determined by the beam profile as defined in the beam.data file and 
      their decay times. 

   neutron.mac: macrofile to show the incident of low energy neutrons on an 
      user specified NaI target and the decays of the induced radio-isotopes.

   ne24.mac: this shows the decays of Ne-24 to Na-24 in variance reduction MC 
      mode. Further decays of Na-24 are not simulated by applying the 
      nucleuslimits in RadioactiveDecay. Two runs are carried out.
		  One with the bracjing ratio biasing applied and one without. 

   isotopes.mac: to show the decays of a number of different isotopes in a 
      single macro file.

   f24.mac: to show the different treatments one can apply to the decays of F24.
      i)   the complete decay chain from F24 to Mg24, in analogue mode; 
      ii)  the complete chain, but in variance reduction mode; 
      iii) restrict to the decay of F24 only in analogue mode; iv) restrict to 
           the decay of F24 only but in variance reduction mode.

   as74.mac: The decays of As74 which has a rather complicated decay scheme. 
      i)  in analogue MC mode; 
      ii) in variance reduction MC mode.
    
   UserRadDataPb210Test.mac: show how the user can define its own radioactive 
      decay datafile
    
   UserEvapDataBiTest.mac: show how the user can define its own 
      photo-evaporation datafile 
	
   No252.mac: show how to simulate Radoactive decay for nuclei with Z>100 
      based on user datafile

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