Welcome to PHOXTROT (PHOton Xsections for TRanspOrT). This repository contains a collection of cross sections useful to describe the production of photons in a hadronic medium. See for example Phys. Rev. D 99, 114021 (2019) for further details.
PHOXTROT contains cross sections for two types of processes:
- 2 <-> 2 Scatterings: π + π -> ρ + γ and π + ρ -> π + γ
- Bremsstrahlung: π + π -> π + π + γ
The presented cross sections for 2 <-> 2 scatterings rely on a theoretical framework
described by S. Turbide, R. Rapp and C. Gale in
Phys. Rev. C 69, 014903 (2004).
The matrix elements are taken from the
PhD thesis
of Simon Turbide.
The presented cross sections for bremsstrahlung processes are calculated within the one-boson exchange model.
In this repository, the differential and total cross sections are presented in C++ readable format. The entire repository is wrapped by a CMake routine to easily produce tables and plots for the given processes.
To properly use PHOXTROT, make sure the following prerequisites are met:
- cmake >= 3.15.4
- the GNU Scientific Library >= 2.0
- Python modules: matplotlib, numpy, seaborn, argparse, os, sys, glob
To build PHOXTROT and create the executable, use the following commands:
mkdir build
cd build
cmake ..
make phoxtrot
The executable phoxtrot is located in the build directory. Upon
execution, txt files for the differential and total cross section are created
that contain the computed cross sections for varying values of theta, k and s. To
execute phoxtrot, create the cross section files and plot them, type
make plots
The generated cross section files can then be found in PATH_TO_BUILD/tables
and the corresponding plots are located in PATH_TO_BUILD/plots. Note that the tables and plots for all differential cross sections are created at a fixed value of √s = 1.0 GeV. If necessary, this value may be changed in the functions TwoToTwo_writing::write_Diff_Xsec_PiRho_PiGamma, TwoToTwo_writing::write_Diff_Xsec_PiPi_RhoGamma, Brems_writing::write_dSigma_dk, and Brems_writing::write_dSigma_dTheta.