megasim

Pythia to HepMC to Delphes HEP-simulation chain

m.mieskolainen@imperial.ac.uk, 2023

Preliminaries

Conda environment

(If you like)

wget https://repo.anaconda.com/archive/Anaconda3-2023.03-Linux-x86_64.sh

Then execute the installer with bash filename.sh.

conda create -y --name megasim python==3.10.10
conda activate megasim

conda install -c anaconda cmake
conda install -c conda-forge gxx_linux-64==11.1.0
conda install -c conda-forge gcc_linux-64==11.1.0

Override system default compiler

ln -s $CONDA_PREFIX/bin/x86_64-conda-linux-gnu-gcc ~/.local/bin/gcc
ln -s $CONDA_PREFIX/bin/x86_64-conda-linux-gnu-g++ ~/.local/bin/g++
export PATH=$HOME/.local/bin:$PATH

Set the system library path (important for GLIBC)

export LD_LIBRARY_PATH="$CONDA_PREFIX/lib:$LD_LIBRARY_PATH"

CVMFS environment at lxplus / lx

(We need C++14 compatible g++, the environment below is tested to work at lx02 centos7)

source /cvmfs/sft.cern.ch/lcg/views/setupViews.sh LCG_102 x86_64-centos7-gcc11-opt

Installation

ROOT

(If not already)

cd $HOME/local

# Pick suitable pre-compiled ROOT (Ubuntu, Centos etc.)
wget https://root.cern/download/root_v6.28.02.Linux-ubuntu22-x86_64-gcc11.3.tar.gz
tar -xzvf root_v6.28.02.Linux-ubuntu22-x86_64-gcc11.3.tar.gz

# Setup environment
source $HOME/local/root/bin/thisroot.sh

HepMC2

tar -xvf hepmc2.06.11.tgz
cd HepMC-2.06.11

export HEPMC2=$HOME/local/HEPMC2
./configure --with-momentum=GEV --with-length=MM --prefix=$HEPMC2/HepMC-2.06.11/build
make -j8 && make install
cd ..

Rivet

(RESERVATION -- not needed)
https://gitlab.com/hepcedar/rivet/-/blob/release-3-1-x/doc/tutorials/installation.md

mkdir -p scratch/rivet
cd scratch/rivet
wget https://gitlab.com/hepcedar/rivetbootstrap/raw/3.1.7/rivet-bootstrap
chmod +x rivet-bootstrap

export RIVET=$HOME/local/RIVET
INSTALL_PREFIX=$RIVET MAKE="make -j8" ./rivet-bootstrap
cd ../..

Pythia 8

wget https://pythia.org/download/pythia83/pythia8309.tgz

tar -xzvf pythia8309.tgz
cd

export PYTHIA8=$HOME/local/PYTHIA8
./configure --with-hepmc2=$HEPMC2/HepMC-2.06.11/build --prefix=$PYTHIA8/Pythia-8.3.09/build
make -j8 && make install
cd ..

Delphes 3

wget http://cp3.irmp.ucl.ac.be/downloads/Delphes-3.5.0.tar.gz

tar -zxf Delphes-3.5.0.tar.gz
cd Delphes-3.5.0

make -j8
cd ..

Simulation

A. Event generation

source run_pythia.sh

B. Delphes detector simulation

source run_delphes.sh

Links and others

https://pythia.org/latest-manual/Welcome.html
https://cp3.irmp.ucl.ac.be/projects/delphes
http://cp3.irmp.ucl.ac.be/downloads/RootTreeDescription.html
https://github.com/scikit-hep/pyhepmc
https://gitlab.cern.ch/hepmc/HepMC3

See Delphes analysis ROOT-macro examples under Delphes-3.5.0/examples