Skip to content

Latest commit

 

History

History
64 lines (42 loc) · 1.98 KB

README.md

File metadata and controls

64 lines (42 loc) · 1.98 KB
Raw

PYTHIA 8 in Geant4 example

  1. Installation
    mkdir build
    cd build

    source /afs/cern.ch/sw/lcg/contrib/gcc/4.9/x86_64-slc6-gcc49-opt/setup.sh
    source /afs/cern.ch/sw/lcg/external/geant4/10.1/x86_64-slc6-gcc49-opt/CMake-setup.sh
    source /afs/cern.ch/sw/lcg/app/releases/ROOT/5.34.25/x86_64-slc6-gcc48-opt/root/bin/thisroot.sh
    export PYTHIA8DATA=/afs/cern.ch/sw/lcg/external/MCGenerators_lcgcmt67b/pythia8/186/x86_64-slc6-gcc47-opt/xmldoc
    export ROOTSYS=/afs/cern.ch/sw/lcg/app/releases/ROOT/5.34.25/x86_64-slc6-gcc48-opt/root/

    cmake -DHEPMC_ROOT_DIR='/afs/cern.ch/sw/lcg/external/HepMC/2.06.08/x86_64-slc6-gcc47-opt/' \
      -DPYTHIA8='/afs/cern.ch/sw/lcg/external/MCGenerators_lcgcmt67b/pythia8/186/x86_64-slc6-gcc47-opt/'  \
      -DCMAKE_CXX_COMPILER='/afs/cern.ch/sw/lcg/contrib/gcc/4.9/x86_64-slc6-gcc49-opt/bin/g++' \
      -DCMAKE_INSTALL_PREFIX=. ..

    make
  1. Choosing the primary generator

2.1. Pythia 8 called for each event

Detail of Pythia processes and beam/target, energy need to be specified in Geant macro. Examples:

   hepmc_pythia8.in :

    /generator/select pythia8
    /generator/pythia8/read "HardQCD:all = on"
    /generator/pythia8/read "PhaseSpace:pTHatMin = 20."
    /generator/pythia8/init 2212 2212 14000.
    /run/beamOn 1

2.2. Pythia8 event saved in HepMC format to ASCII file, read by Geant4:

   hepmc_ascii.in:

     /generator/select hepmcAscii
     /generator/hepmcAscii/open ../tools/pythia8ToAscii/example_MyPythia8.dat
     /run/beamOn 1

2.3. Pythia8 event saved in HepMC format to ROOT file, read by Geant4:

   hepmc_root.in:

     /generator/select hepmcRoot
     /generator/hepmcRoot/open ../data/pythia8ToRoot/PythiaInHepMC_140GeV.root
     /run/beamOn 1
  1. Running an example

4.1 Without GUI

    ./HepMCEx03 hepmc_pythia8.in

4.2 With GUI

    ./HepMCEx03