Tutorial_generators

1. Instructions for installing Madgraph

    tar -xzf MG5_aMC_v2.9.2.tar.gz
   
    cd MG5_aMC_v2_9_2
   
    ./bin/mg5_aMC
   

   (The first time you run Madgraph, you can be asked wether you want to update the software: New Version of MG5 available! Do you want to update your current version?[n, y, on_exit][60s to answer] Answer >n)

   Now you are ready to generate processes

2. Instructions for installing Pythia

    MG5_aMC>install mg5amc_py8_interface
   

3. Generate the process mu mu -> H -> ZZ -> 4mu

   The Higgs boson is produced through WW fusion: mu+ mu- -> H vm vm~ -> Z Z* vm vm~ -> mu+ mu- mu+ mu- vm vm~

   In order to generate this process in Madgraph, we do:

    MG5_aMC>generate mu+ mu- > H vm vm~ , (H > Z mu+ mu- , Z > mu+ mu-)
   

   Save the process in the folder "signal"

    MG5_aMC>output signal
   

4. Feynman diagrams

   We can see the Feynman diagrams of the generated process in the file:

   MG5_aMC_v2_9_2/signal/SubProcesses/P1_ll_hvlvl_h_zll_z_ll/matrix1.ps

   2 diagrams have been generated

5. generate events

   In the folder MG5_aMC_v2_9_2/signal/Cards several cards that define the parameters for the generation are created

   Open and modify the card run_card.dat

   We want to generate 1000 events at a center-of-mass energy of 1500 GeV

   In Madgraph, execute the following command:

    MG5_aMC>launch signal/
   

   In order to activate Pythia:

    >shower=Pythia8
    >done
   

   Then you are asked: Do you want to edit a card (press enter to bypass editing)? press enter

   A html file will be opened in your browser