-------------------------------------------------------------------

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

                            dmparticle  
                            ----------

                       V. Grichine (25.03.2017)

    Geant4 application for testing of dark matter particles and processes 
                      (based on TestEm8 and monopole examples)

This is very preliminary and simplified Geant4 example for light dark matter (LDM) particles. 
It consists of LDM bremsstrahlung process (in G4LDMPhysics constructor) 
for protons creating G4LDMPhotons. 
The latter decays creating G4LDMHi and G4LDMHiBar LDM scalar particles. They 
can scatter on nucleons and electrons. 

The first version has electromagnetic processes only. Hadron constructors can be added similarly 
to HadrN examples.

More LDM processes will be added according to experiment requirements



 1- GEOMETRY DEFINITION

     The geometry consists of a single block of a homogenous material,
     placed in a world.

     Parameters define the geometry :
 	- the material of the box 
	- the thickness of the box 
	- the tranverse dimension of the box 

     The default is 130 cm of tungsten.
     Equivalent UI commands are following:
        /testex/det/setMat G4_W
        /testex/det/sizeX  130 cm
        /testex/det/sizeYZ  30 cm

     The default geometry is constructed in DetectorConstruction class,
     but all of the above parameters can be changed interactively via
     the commands defined in the DetectorMessenger class. 

 2- PHYSICS LIST

    Physics Lists include EM standard physics and decay physics, additional 
    dark matter particle physics imlemented inside PhysicsList method. By
    default DMLPhoton is defined with the mass 0.5 GeV.
    To define different mass of this photon or enable DMLHi, DMLHiBar
    command line commands should be applied.

 3- AN EVENT : THE PRIMARY GENERATOR

     The primary kinematic consists of a single particle which hits the
     block perpendicular to the input face. The type of the particle
     and its energy are set in the PrimaryGeneratorAction class, and can
     changed via the G4 build-in commands of ParticleGun class (see
     the macros provided with this example).
     The default is proton 100 GeV

 4- HOW TO START ?

     - execute Test  in 'batch' mode from macro files
 	% dmparticle dmparticle.in
 	% dmparticle dmparticle.in 0.2 0.4

     two extra numbers are masses in GeV of DMLPhoton and DMLHi

 5- HISTOGRAMS

     The result is five histograms:
				- energy deposition along the target

     The histogram is saved in Root file.

