CORSIKA 8 Framework for Particle Cascades in Astroparticle Physics

The purpose of CORSIKA is to simulate any particle cascades in astroparticle physics or astrophysical context. A lot of emphasis is put on modularity, flexibility, completeness, validation and correctness. To boost computational efficiency different techniques are provided, like thinning or cascade equations. The aim is that CORSIKA remains the most comprehensive framework for simulating particle cascades with stochastic and continuous processes.

The software makes extensive use of static design patterns and compiler optimization. Thus, the most fundamental configuration decision of the user must be performed at compile time. At run time model parameters can still be changed.

CORSIKA 8 is by default released under the GPLv3 license. See license file which is part of every release and the source code.

If you use, or want to refer to, CORSIKA 8 please cite "Towards a Next Generation of CORSIKA: A Framework for the Simulation of Particle Cascades in Astroparticle Physics", Comput.Softw.Big Sci. 3 (2019) 2. We kindly ask (and require) any relevant improvement or addition to be offered or contributed to the main CORSIKA 8 repository for the benefit of the whole community.

When you plan to contribute to CORSIKA 8 check the guidelines outlined here: coding guidelines. Code that fails the review by the CORSIKA author group must be improved before it can be merged in the official code base. After your code has been accepted and merged, you become a contributor of the CORSIKA 8 project (code author).

IMPORTANT: Before you contribute, you need to read and agree to the collaboration agreement. The agreement can be discussed, and eventually improved.

We also want to point you to the MCnet guidelines, which are very useful also for us.

Get in contact

• Connect to https://gitlab.iap.kit.edu register yourself and join the "Air Shower Physics" group. Write to one of the steering comittee members (https://gitlab.iap.kit.edu/AirShowerPhysics/corsika/-/wikis/Steering-Committee) in case there are problems with that.

• Connect to corsika-devel@lists.kit.edu (self-register at https://www.lists.kit.edu/sympa/subscribe/corsika-devel) to get in touch with the project.

• Register on the corsika slack channel.

Installation

CORSIKA 8 is tested regularly at least on gcc11.0.0 and clang-14.0.0.

Prerequisites

You will also need:

• Python 3 (supported versions are Python >= 3.6), with pip
• conan (via pip)
• cmake
• git
• g++, gfortran, binutils, make
• optional: FLUKA (see below)

On a bare Ubuntu 20.04, just add:

sudo apt-get install python3 python3-pip cmake g++ gfortran git doxygen graphviz

On a bare CentOS 7 install python3, pip3 (pip from python3) and cmake3. Any of the devtools 7, 8, 9 should work (at least). Also initialize devtools, before building CORSIKA 8:

source /opt/rh/devtoolset-9/enable

CORSIKA 8 uses the conan package manager to manage our dependencies. Currently, version 1.55.0 or higher is required. If you do not have Conan installed, it can be installed with:

pip install --user conan~=1.57.0

Compiling

Once Conan is installed, follow these steps to download and install CORSIKA 8:

git clone --recursive git@gitlab.iap.kit.edu:AirShowerPhysics/corsika.git
mkdir corsika-build
cd corsika-build
../corsika/conan-install.sh
cmake ../corsika -DCMAKE_BUILD_TYPE="RelWithDebInfo" -DCMAKE_INSTALL_PREFIX=../corsika-install
make -j8
make install

FLUKA support

For legal reasons we do not distribute/bundle FLUKA together with CORSIKA 8. If you want to use FLUKA as low-energy hadronic interaction model, you have to download it separately from (http://www.fluka.org/), which requires registering there as FLUKA user. You need to download binaries suitable for your system (check compiler and glibc versions) and unpack the binaries into a directory of your choice. You also need the data archive (fluka20xy.z-data.tar.gz) unpacked in the same directory. To compile CORSIKA 8 with FLUKA, you need to specify the path of libflukahp.a when invoking cmake with the option -DC8_FLUKALIB=<path>. CMake will print a status message indicating whether FLUKA support is enabled or disabled when the library is (not) found.

Installation (using docker containers)

There are docker containers prepared that bring all the environment and packages you need to run CORSIKA. See docker hub for a complete overview.

Prerequisites

You only need docker, e.g. on Ubunut: sudo apt-get install docker and of course root access.

Compiling

Follow these steps to download and install CORSIKA 8, master development version

git clone --recursive https://gitlab.iap.kit.edu/AirShowerPhysics/corsika.git
sudo docker run -v $PWD:/corsika -it corsika/devel:clang-8 /bin/bash
mkdir build
cd build
../corsika/conan-install.sh
cmake ../corsika -DCMAKE_INSTALL_PREFIX=../corsika-install
make -j8
make install

Runing Unit Tests

To run the Unit Tests, just type ctest in your build area.

Running examples

To see how a relatively simple hadron cascade develops, see examples/cascade_example.cpp for a starting point.

To run the cascade_example, or any other CORSIKA 8 application, you must first compile it wrt. to the CORSIKA 8 header-only framework. This can be done best by copying e.g. corsika-install/share/corsika/examples/ to your working place (e.g. corsika-work).

cd corsika-work

Next, you need to define the environment variable corsika_DIR to point to, either, your build, or your install area. Thus, e.g.

export corsika_DIR=<dir where you installed CORSIKA 8 to, or where you build it>

You also need to define the environment variable CORSIKA_DATA to point to your modules/data folder where you cloned the corsika repository. Thus, e.g.

export CORSIKA_DATA=<modules/data dir where you cloned CORSIKA 8 to>

Then compile your example/application with

cmake .
make
bin/cascade_example 

Generating doxygen documentation

To generate the documentation, you need doxygen and graphviz. If you work with the docker corsika/devel containers this is already included. Otherwise, e.g. on Ubuntu 18.04, do:

sudo apt-get install doxygen graphviz

Switch to the corsika build directory and do

make docs
make install

open with firefox:

firefox ../corsika-install/share/corsika/doc/html/index.html