Neutrino Monte Carlo Simulator with Apptainer

Welcome! This repository will help to install ROOT and neutrino Monte Carlo simulation (GENIE) software inside an independent Apptainer:

Requirements

• Installed Apptainer in your system
• Approx 10 GB free space

---

Apptainer Installation Guide

• I would highly recommend to follow official apptainer installtion instructions at Installing Apptainer. However some basic commands are given below. If you already have apptainer installed, skip this section.
  • In Ubuntu

  sudo apt update
  sudo apt install -y software-properties-common

  sudo add-apt-repository -y ppa:apptainer/ppa
  sudo apt update
  sudo apt install -y apptainer

  • In Fedora

  sudo dnf install -y apptainer

  • In AlmaLinux/CentOS

  sudo dnf install -y epel-release
  sudo dnf install -y apptainer

  • In Mac/Windows, install apptainer via virtual machine (VM) or WSL2 (for Windows). For Mac follow: Installation in Mac, for Windows follow: Installtion in Windows
  • To check installtion, run

  apptainer --version

  It should show your apptainer version. For me it was apptainer version 1.4.2

---

Setup Instructions

Step 1: Building apptainer sandbox

Apptainer sandbox can be built in two different ways: Option A and Option B. Option A is more simpler and easier way.

Option A: Using prebuild sif image

Step I: Download sif image

Create a directory IIFC_GENIE and download genie.sif from Google Drive and put it inside IIFC_GENIE directory

Step II: Make sandbox using genie.sif

apptainer build --sandbox genie_sandbox/ genie.sif

Step III: Enter the apptainer shell

apptainer shell --writable genie_sandbox/

Step IV: Set environment for GENIE

cd /opt/mywork/
source do_end_genie.sh

Step V: Check genie

genie

You should see Version 3.04.00 on your screen

Step VI: Clone git repository

git clone https://github.com/amitpal96/MC_tutorial.git
cd MC_tutorial

Step VII: For further use of GENIE

Enter the apptainer shell with

apptainer shell --writable genie_sandbox/

Click here to view Option B steps

Option B: Build apptainer sandbox from scratch

This is more complicated and time taking process. I would recommend to go with Option A

Step I: Download tar files

Download tarballs of all required package from: Google Drive and place all of them inside **MC_tutorial** directory

Step II: Build the first apptainer

Use the provided setup_container1.def file to build a sandbox environment called sandbox_container1:

apptainer build --sandbox sandbox_container1/ setup_container1.def

Step III: Build the second apptainer using setup_container2.def:

apptainer build --sandbox sandbox_container2/ setup_container2.def

This step will take ~2 hours as it builds ROOT from source file.

Step IV: Enter apptainer and check root version

apptainer shell --writable sandbox_container2

root

This should show Welcome to ROOT 6.30/02

Step V: GENIE installtion inside the apptainer

cd /opt/GENIE
chmod +x do_end_genie.sh
./do_end_genie.sh

This will setup environment for GENIE.

./configure --prefix=/opt/GENIE_build --enable-atmo --enable-lhapdf6 --with-lhapdf6-lib=/opt/lhapdf_install/lib --with-lhapdf6-inc=/opt/lhapdf_install/include --with-log4cpp-inc=/opt/log4cpp_install/include --with-log4cpp-lib=/opt/log4cpp_install/lib --with-pythia6-lib=/opt/pythia/v6_428/lib --with-pythia6-inc=/opt/pythia/v6_428/inc --with-libxml2-lib=/opt/libxml2_install/lib with-libxml2-inc=/opt/libxml2_install/include/libxml2

make -j4

Congratulations! You have finally installed GENIE. If you encounter any error, do once

make clean
make -j4

If it does not resolve, contact amit.pal@niser.ac.in.

Step VI: For further use of GENIE

Once GENIE is installed properly, you just need to do,

apptainer shell --writable sandbox_container2

cd /opt/GENIE
./do_end_genie.sh

This should set up your GENIE. You are good to go.

Step 2: Generate first event using GENIE

cd /opt/mywork/
gevgen -r 3 -n 100 -p 14 -t 1000010020 -e 1.0 --cross-sections gxspl-NUsmall.xml

This will create 100 neutrino events. If you do ls, you can see two new files have been created: genie-mcjob-3.status and gntp.3.ghep.root.