fiatlux

API for LUXqed methodology in global PDF fits.

Project summary and aim

The aim of libfiatlux is to provide a blackbox tool which computed the photon PDF at a given Q value using the LUX approach by Manohar, Nason, Salam and Zanderighi in arXiv:1607.04266 and arXiv:1708.01256. The output of this repository is a C++ library which can be imported and shared to other programs.

The library implements following features:

• Computes LUX photon by subdividing in elastic, inelastic and msbar components
• Allow variations of parameters to estimate uncertainties
• Generic interface to F2, FL and alpha QED: you can plug APFEL or any other evolution code.

Release and Tag policy

The library is tagged and released when a major and stable status is achieved.

Testing

Manual testes are available in the examples folder.

Installation

Python library

pip install .

C++ library

libfialux depends on the following libraries:

• pkg-config
• yaml-cpp

optinally to build the examples:

• lhapdf
• apfel

please ensure to have the dependencies correctly installed and in your PATH before installing libfiatlux.

Configurations

Possible configurations:

cmake .

or (recommended):

mkdir build
cd build
cmake ..

You can control the optional flags with ccmake or from cmd line, the most relevant flags are:

CMAKE_INSTALL_PREFIX
ENABLE_EXAMPLES

On the command line, options are controlled appending a -D flag. For example:

cmake .. -DENABLE_EXAMPLES=on

Documentation

Code documentation

The code is documented with Doxygen (folder doc/), if you find methods or classes not fully documented open a issue request.

Citation policy

If you decide to use this code please cite the following papers:

• The NNPDF3.1QED paper which is the fundamental motivation for this library arXiv:1712.07053
• The original LUX paper arXiv:1607.04266
• The long/complete version of LUX arXiv:1708.01256
• The GD11-P fit code from: The HERMES Collaboration [A. Airapetian et al.], JHEP 05 (2011) 126.
• The CLAS parametrization used in hep-ph/0301204 (CLAS) and described in hep-ph/9901360.