Installation

Download

A tar archive of the HEJ 2 source code can be downloaded and decompressed with the command:

curl https://hej.hepforge.org/downloads?f=HEJ_2.0.tar.gz | tar -xz

To obtain the latest stable HEJ version, HEJ_2.0.tar.gz should be replaced by HEJ.tar.gz.

Alternatively, the HEJ source code can be obtained by installing the git version control system. and running:

git clone https://phab.hepforge.org/source/hej.git

We also provide a Docker image containing a HEJ 2 installation on. This image can be pulled with:

docker pull hejdock/hej

When using the Docker image the remaining installation steps can be skipped.

Prerequisites

Before installing HEJ 2, you need the following programs and libraries:

If you want to include finite top mass corrections in Higgs boson + jets production, you additionally need version 2 of the QCDLoop library. HEJ 2 supports versions 2 and 3 of HepMC if it is installed, but does not require it. Additional HEJ 2 can be interfaced to rivet, which requires HepMC version 2.

Compilation

To compile and install HEJ 2 run:

cmake source/directory -DCMAKE_INSTALL_PREFIX=target/directory
make install

source/directory is the directory containing the file CMakeLists.txt. If you omit -DCMAKE_INSTALL_PREFIX=target/directory HEJ 2 will be installed to some default location.

In case some of the aforementioned prerequisites are not found by cmake you can give a hint by adding an additional argument -Dlibname_ROOT_DIR=/directory/with/library, where libname should be replaced by the name of the library in question.

To not include specific packages one can add -DEXCLUDE_packagename=TRUE to cmake, e.g. by setting -DEXCLUDE_rivet=TRUE HEJ 2 will not be interfaced to rivet even if rivet is available on the system.

Testing

To test your installation, download the NNPDF 2.3 PDF set with:

lhapdf install NNPDF23_nlo_as_0119

and run:

make test