Program name: "GenEx" Generator

Warnings:

1. This is development verison, so if you find any errors/problems do not hesitate to write.

2. The program was written by means of high standards, however, the authors are not responsible for any damages that result from the use of this program. Use it at your own risk.

Authors:

Radoslaw Kycia rkycia@pk.edu.pl
Cracow University of Technology Krakow, Poland

Janusz Chwastowski jchwastowski@pk.edu.pl
Cracow University of Technology Krakow, Poland

Rafal Staszewski rafal.staszewski@gmail.com
Institute of Nuclear Physics, Polish Academy of Sciences Krakow, Poland

Jacek Turnau jacek.turnau@ifj.edu.pl
Institute of Nuclear Physics, Polish Academy of Sciences Krakow, Poland

Brief descritpion:

Generator provides universal scheme for HEP generation. It is configured for models of exclusive production of hadron pairs. Currently it implements model of Lebiedowicz and Szczurek [1] (see also [2]) of reaction (see [3]) \f$2p->2p + \pi^{+} + \pi^{-}\f$ and \f$2p->2p + K^{+} + K^{-}\f$, but it is not restricetd to these models.

Bibliography:

[1] P. Lebiedowicz, A. Szczurek ,,Exclusive \f$2p->2p + \pi^{+} + \pi^{-}\f$ reaction: from the threshold to LHC'', arXiv:0912.0190

[2] L.A. Harland-Lang, V.A. Khoze , M.G. Ryskin, W.J. ,,Stirling The phenomenology of central exclusive production at hadron colliders'', arXiv:1204.4803 [hep-ph]

[3] A. Szczurek, P. Lebiedowicz, arXiv:1110.4787[hep-ph]

[4] S. Jadach ,,Rapidity Generator for Monte-Carlo Calculations of Cylindrical Phase Space'' Comp. Phys. Comm. 9 (1975) 297

[5] S. Jadach ,,Foam: A General-Purpose Cellular Monte Carlo Event Generator'', arXiv:physics/0203033 [physics.comp-ph]

[6] ROOT framework, (access date: 04/01/2013): http://root.cern.ch/drupal/

[7] TFoam documentation (access date: 04/01/2013): http://root.cern.ch/root/html/TFoam.html

[8] Gnu Scientific Library, (access date: 04/01/2013): http://www.gnu.org/software/gsl/

[9] Doxygen documentation, (access date: 04/01/2013): http://www.stack.nl/~dimitri/doxygen/

Dependence:

Program depends highly on ROOT framework [6]. Every properly installed ROOT with FOAM generator(default for new ROOTs) should work. For FOAM consult [5].

For compiling (GNU) make system and c++ compiler is required - if ROOT was installed properly from the source then all necessary things to run generator should be installed.

There is a simple (GNU) Makefile available. Before run please check if locations to ROOT folder, ROOT includes and ROOT libraries in your linking system were set properly.

Warnings:

1. Underlaying random number generator TRandom3 from ROOT package has the period = 2^19937-1. It is big but finite number. It should be large enough for any today's applications, however anyone who seriously consider generation of much larger set of events should change the generator, change the seed/use the presistency or use hardware random number generators.
2. It is assumed that first two particles are leading ones.

Commands

• To compile and run type: make all

  Executable is in ./bin directory

• To compile and run type: make run

• To run example test type: make test

  Restoring oryginal Generator.dat (with comments) is by selection 0 option.

• To restore folder to original state type: make clean

• To count lines of the program type: make line_count

• To generate Doxygen documentation [9] type: make Generate-doc

Directory structure:

• ./ - main directory contains Makefile, configuration file Generator.dat and scripts that perform various operations.
• /bin - contains main.x generator program appears after compilation. It is wiped by make clean command.
• /include - contains header files.
• /src - contains source files and the main generator file \b main.cxx
• /build - is temporary directory for building. It is created by main run command and deleted with all the content by make clean command.
• /EVENTS - contains files with saved events form the run.
• /MODEL_DATA - contains configuration (text) files for different models (e.g. matrix elements) used in generation.
• /ACCEPTANCE_CUTS - contains files with cuts.
• /Tests - contains sorted generator configuration files sortedConfigLog.log which are used in the second mode of generator running make test

Setup:

The main configuration file is Generator.dat. It is heavily commented.