This code provides a library that can be used to evaluate dipole amplitude computed using light cone perturbation theory, as a function of dipole size r (unit: GeV^(-1)), impact parameter b (unit: GeV^(-1)), and the angle between r and b.

Note that the calculation is only valid in the perturbative small-r and small-b region. Consequently results at non-perturbatively large r and b are not included in the grids.

A. Dumitru, H. Mäntysaari, R. Paatelainen, 2021 arXiv:2103.11682, Phys.Lett.B 820 (2021) 136560, which is based on arXiv:2010.11245, A. Dumitru, R. Paatelainen, Phys.Rev.D 103 (2021) 3, 034026

Questions and comments to [email protected]

The code can be built using cmake (needs GSL)

mkdir build
cd build
cmake ..
make

This generates a static library build/dipole/liblcptdipole.a which can be linked to an another C++ project. The necessary datafiles can be found from the data directory. The filename shows the corresponding Bjorken-x, strong coupling constant as and infrared regulator m (in GeV).

See src/example.cpp as an example on how to use the library. The attached dipole_amplitude.ipynb Jupyter notebook can also be used to study the dipole amplitudes.

The code in the cmake directory is licensed under the Boost Software License, Version 1.0.

Everything else is licensed under the Attribution 4.0 International (CC BY 4.0) license.