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[Licence| Download | New Version Template] adsm_v2_0.tar.gz(4190 Kbytes)
Manuscript Title: MC-TESTER v. 1.23: a universal tool for comparisons of Monte Carlo predictions for particle decays in high energy physics
Authors: N. Davidson, P. Golonka, T. Przedzinski, Z. Was
Program title: MC-TESTER, version 1.23 and version 1.24.4
Catalogue identifier: ADSM_v2_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 182(2011)779
Programming language: C++, FORTRAN77 Tested and compiled with: gcc 3.4.6, 4.2.4 and 4.3.2 with g77/gfortran.
Computer: Tested on various platforms.
Operating system: Tested on operating systems: Linux SLC 4.6 and SLC 5, Fedora 8, Ubuntu 8.2 etc.
Keywords: particle physics, decay simulation, Monte Carlo methods, invariant mass distributions, programs comparison.
Classification: 11.9.

External routines: HepMC (https://savannah.cern.ch/projects/hepmc/), PYTHIA8 (http://home.thep.lu.se/~torbjorn/Pythia.html), LaTeX (http://www.latex-project.org/)

Does the new version supersede the previous version?: Yes

Nature of problem:
The decays of individual particles are well defined modules of a typical Monte Carlo program chain in high energy physics. A fast, semi-automatic way of comparing results from different programs is often desirable for the development of new programs, in order to check correctness of the installations or for discussion of uncertainties.

Solution method:
A typical HEP Monte Carlo program stores the generated events in event records such as HepMC, HEPEVT or PYJETS. MC-TESTER scans, event by event, the contents of the record and searches for the decays of the particle under study. The list of the found decay modes is successively incremented and histograms of all invariant masses which can be calculated from the momenta of the particle decay products are defined and filled. The outputs from the two runs of distinct programs can be later compared. A booklet of comparisons is created: for every decay channel, all histograms present in the two outputs are plotted and parameter quantifying shape difference is calculated. Its maximum over every decay channel is printed in the summary table.

Reasons for new version:
Interface for HepMC Event Record is introduced. Setup for benchmarking the interfaces, such as τ-lepton production and decay, including QED bremsstrahlung effects is introduced as well. This required significant changes in the algorithm. As a consequence, a new version of the code was introduced.

Summary of revisions:
  • HepMC interface introduced
  • installation and configuration scripts added
  • visualization options added
  • introduced options useful for use of the program on distributed systems, such as the grid
  • comments regarding source code added

Only the first 200 decay channels that were found will initialize histograms and if the multiplicity of decay products in a given channel was larger than 7, histograms will not be created for that channel.

Additional comments:
New features:
HepMC interface, use of lists in definition of histograms and decay channels, filters for decay products or secondary decays to be omitted, bug fixing, extended flexibility in representation of program output, installation configuration scripts, merging multiple output files from separate generations.

Running time:
Varies substantially with the analyzed decay particle, but generally speed estimation of the old version remains valid. On a PC/Linux with 2.0 GHz processors MC-TESTER increases the run time of the τ-lepton Monte Carlo program TAUOLA by 4.0 seconds for every 100 000 analyzed events (generation itself takes 26 seconds). The analysis step takes 13 seconds; LATEX processing takes additionally 10 seconds. Generation step runs may be executed simultaneously on multiprocessor machines.