Event generation¶
Our simulation framework supports HepMC3
and stdhep
data formats for the input of signal events from Monte Carlo event generators.
As an example we will use a Whizard
event generator that is included in the software release.
Generating H -> bb sample in Whizard¶
A reference configuration file for generating a HepMC3
sample of mu+ mu- -> H + neutrinos -> bb + neutrinos
process is available at mucoll-benchmarks/generation/signal/whizard/mumu_H_bb_3TeV.sin
.
During the generation process a number of compilation files are created for each subprocess, therefore it is better to run it in a separate folder, like this:
mkdir gen_Hbb && cd gen_Hbb
whizard ../mucoll-benchmarks/generation/signal/whizard/mumu_H_bb_3TeV.sin
This process can be time-consuming, therefore to speed up the process you can copy the pre-generated sample and use it in the next step:
or if you don't have access to CVMFS:
Madgraph¶
Another popular event generator is Madgraph5_aMC@NLO
.
A complete tutorial on how to use it can be found in this presentation.
Particle gun¶
It is sometimes useful for performance studies to simulate events with single particles (muons, pions, electrons etc) with specific parameters.
A dedicated Python script allows to generate an LCIO file with stable particles, represented by LCIO::MCParticle
objects.
For example to generate 100 events with 1 muon/event having p_T = 10 GeV
and polar angle randomly distributed in the range [10deg, 170deg]
:
python ../mucoll-benchmarks/generation/pgun/pgun_lcio.py -e 100 -p 1 --pdg -13 13 --pt 10 --theta 10 170 -- pgun_mu.slcio
NOTE: A complete list of supported PDG IDs is defined in the
PDG_PROPS
dictionary in filemucoll-benchmarks/generation/pgun/pdgs.py
, which follow the Monte Carlo numbering scheme from Particle Data Group.