geant4/examples/extended/analysis/A01/.README

//$Id$

///\file "analysis/A01/.README"
///\brief Example A01 README page

/*! \page ExampleA01 Example A01

  Example A01 implements a double-arm spectrometer with wire chambers, 
  hodoscopes and calorimeters.  Event simulation and collection are 
  enabled, as well as event display and analysis.


\section A01_s1 GEOMETRY

   The spectrometer consists of two detector arms.  One arm provides 
   position and timing information of the incident particle while the 
   other collects position, timing and energy information of the particle
   after it has been deflected by a magnetic field centered at the 
   spectrometer pivot point.
 
     - First arm:  box filled with air, also containing:
         - 1 hodoscope (15 vertical strips of plastic scintillator)
         - 1 drift chamber (5 horizontal argon gas layers with a 
                          "virtual wire" at the center of each layer)

     - Magnetic field region: air-filled cylinder which contains
                              the field

     - Second arm:  box filled with air, also containing:
         - 1 hodoscope (25 vertical strips of plastic scintillator)
         - 1 drift chamber (5 horizontal argon gas layers with a 
                          "virtual wire" at the center of each layer)
         - 1 electromagnetic calorimeter: 
               a box sub-divided along x,y and z
               axes into cells of CsI 
         - 1 hadronic calorimeter: 
               a box sub-divided along x,y, and z axes
               into cells of lead, with a layer of 
               plastic scintillator placed at the center 
               of each cell


\section A01_s2 PHYSICS

   This example uses the following physics processes:
     - electromagnetic:
         - photo-electric effect
         - Compton scattering
         - pair production
         - bremsstrahlung
         - ionization
         - multiple scattering
         - annihilation
     - decay
     - transportation in a field

   and defines the following particles:
    -  geantino, charged geantino, gamma, all leptons, 
       pions, charged kaons

   Note that even though hadrons are defined, no hadronic processes 
   are invoked in this example.


\section A01_s3 EVENT

   An event consists of the generation of a single particle which is 
   transported through the first spectrometer arm.  Here, a scintillator 
   hodoscope records the reference time of the particle before it passes
   through a drift chamber where the particle position is measured. 
   Momentum analysis is performed as the particle passes through a magnetic
   field at the spectrometer pivot and then into the second spectrometer 
   arm.  In the second arm, the particle passes through another hodoscope
   and drift chamber before interacting in the electromagnetic calorimeter.
   Here it is likely that particles will induce electromagnetic showers.  
   The shower energy is recorded in a three-dimensional array of CsI 
   crystals.  Secondary particles from the shower, as well as primary 
   particles which do not interact in the CsI crystals, pass into the 
   hadronic calorimeter.  Here, the remaining energy is collected in a 
   three-dimensional array of scintillator-lead sandwiches.

   Several aspects of the event may be changed interactively by the user:
     - initial particle type
     - initial momentum and angle
     - momentum and angle spreads
     - type of initial particle may be randomized
     - strength of magnetic field
     - angle of the second spectrometer arm


\section A01_s4 DETECTOR RESPONSE

  All the information required to simulate and analyze an event is 
  recorded in HITS.  This information is recorded in the following 
  sensitive detectors:

    - hodoscope: 
        - particle time
        - particle position
        - strip ID

    - drift chamber: 
        - particle time
        - particle position
        - layer ID
 
    - electromagnetic calorimeter: 
        - particle position 
        - energy deposited in cell
        - cell ID
  
    - hadronic calorimeter:   
        - particle position 
        - energy deposited in cell
        - cell ID


\section A01_s5 VISUALIZATION
  
   Simulated events can be displayed on top of a representation of the spectrometer.

   vis.mac outputs HepRep version 1 files suitable for viewing in HepRApp or WIRED4.
   Change the /vis/open line from HepRepFile to DAWNFILE to instead
   make .prim files suitable for viewing in DAWN.

   heprep2-000-gz.mac outputs a series of gzipped HepRep version 2 files
   each containing a single event, suitable for viewing in HepRApp or WIRED4

   heprep2zip.mac outputs a single zip file that unzips to a series of
   HepRep version 2 files, each each containing a single event (unzip
   the single file by hand, then view the resulting individial HepRep files).

   heprep2-000-zip.mac outputs a series of zipped HepRep version 2 files
   each containing a single event (not yet viewable unless you
   explicitly unzip them before viewing).

   heprep2.mac outputs a HepRep version 2 file with multiple events
   appended to a single file in an experimental manner

   heprep2gz.mac outputs a HepRep version 2 file with multiple events
   appended to a single file in an experimental manner

   Any of the heprep mac files above with the name bheprep (for instance
   bheprep2zip.mac) will write a Binary HepRep version 2 file, readable only
   by WIRED4 (not by HepRApp).


\section A01_s6 ANALYSIS

   This example implements an AIDA-compliant analysis system which
   creates histograms, ntuples and plotters.  If you have built Geant4 with
   the option to use analysis (answering yes to the appropriate question in
   ./Configure -build), then at the completion of a simulation run,
   a file A01.aida is produced which contains these data structures.
   This file can be used as an input to the Java Analysis Studio (JAS) which allows
   the histograms and ntuples to examined, manipulated, saved and printed.

   For further details, see also \link ExampleA01AIDA README.AIDA \endlink.
*/