ESEPP is a multipurpose event generator developed for the Monte Carlo simulation of unpolarized elastic scattering of charged leptons (electrons, positrons, muons, and antimuons) on protons. The generator takes into account the lowest-order QED radiative corrections to the Rosenbluth cross section including first-order bremsstrahlung without using the soft-photon or ultrarelativistic approximations. A detailed theoretical description of the generator is given in arXiv:1401.2959 or J. Phys. G: Nucl. Part. Phys. 41, 115001 (users of ESEPP are kindly requested to cite this paper).
The event generator is written in the C++ programming language using some ROOT classes. In particular, the TLorentzVector class allows us to simplify working with the four-momenta of particles, the TRandom3 class is used for pseudorandom number generation, and the TFoam class is the basis for event generation and multidimensional phase space integration. The source code of ESEPP is freely available under the GNU GPL license and can be used as a basis for future developments.
To compile the event generator, one should run the make command to build an executable file. A computer with ROOT installed is required (including the MathMore library, the availability of which can be checked with the command root-config --has-mathmore). We use ESEPP under the GNU/Linux operating system, but it should also work on MS Windows and OS X platforms.
The source distribution of ESEPP includes the following files:
- DOCUMENTATION
- README.md (this markdown file)
- input_output.pdf (description of the input parameters and the output files format)
- calc_lepton.pdf (Mathematica/FeynCalc calculation of the lepton bremsstrahlung term)
- calc_proton.pdf (Mathematica/FeynCalc calculation of the proton bremsstrahlung term)
- calc_interference.pdf (Mathematica/FeynCalc calculation of the interference bremsstrahlung term)
- LICENSE (the GNU General Public License)
- SOURCE CODE
- Makefile (makefile to build an executable program)
- Makefile.arch (architecture-dependent part of the makefile)
- esepp.cxx (main source file)
- esepp.h (main header file)
- const.h (header file containing mathematical and physical constants)
- dialog.h (header file for an initial dialogue)
- lepton.h (header file containing the lepton bremsstrahlung term)
- proton.h (header file containing the proton bremsstrahlung term)
- interference.h (header file containing the interference bremsstrahlung term)
- vpol.dat (data file for the vacuum polarization correction, extracted from here)