Gabriele Cosmo\page ExampleHadr00 Example Hadr00
\author V.Ivanchenko \n CERN, Geneva, Switzerland
This example demonstrates a usage of G4PhysListFactory to build Physics List and G4HadronicProcessStore to access cross sections.
GEOMETRY
The Target volume is a cylinder placed inside the World volume. Following UI commands are available to modify the geometry:
/testhadr/TargetMat G4_Pb
/testhadr/WorldMat G4_AIR
/testhadr/TargetRadius 10 mm
/testhadr/TargetLength 20 cm
By default beam direction coincides with the target axis and is Z axis in the global coordinate system. The beam starts in the middle of the target. G4ParticleGun is used as a primary generator. The energy and the type of the beam can be defined via standard UI commands
/gun/energy 15 GeV
/gun/particle proton
PHYSICS
Physics List is defined by its name given in the 3d argument of the of the run command.
./Hadr00 my.macro QGSP_BERT
If 3d argument is not set then by the PHYSLIST environment variable. By default FTFP_BERT Physics List will be instantiated.
CROSS SECTION
At the end of any run the set of cross sections is built and can be printed out for a given projectile particle and a target element, which can be defined via UI commands:
/testhadr/particle pi+
/testhadr/targetElm Pb
/testhadr/verbose 1
The level verbosity above zero provides printout of the cross section table. The energy/momentum limits and number of bins can be set via UI commands:
/testhadr/nBinsE 900
/testhadr/nBinsP 700
/testhadr/minEnergy 1 keV
/testhadr/maxEnergy 1 TeV
/testhadr/minMomentum 1 MeV
/testhadr/maxMOmentum 10 TeV
VISUALIZATION
The vis.mac file can be used as an example of visualization.
HISTOGRAMS
All histograms are provided in decimal logarithmic scale (log10(E/MeV) and log10(p/GeV)) for one projectile particle and one target element. The element is taken from the Geant4 NIST database, natural isotope composition is assumed.
Only ROOT histograms are available.