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[Licence| Download | New Version Template] aexy_v1_0.tar.gz(20640 Kbytes)
Manuscript Title: Computing decay rates for new physics theories with FeynRules and MadGraph5_aMC@NLO
Authors: Johan Alwall, Claude Duhr, Benjamin Fuks, Olivier Mattelaer, Deniz Gizem Öztürk, Chia-Hsien Shen
Program title: MadWidth
Catalogue identifier: AEXY_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 197(2015)312
Programming language: Mathematica and Python.
Computer: Platforms on which Mathematica and Python are available.
Operating system: Operating systems on which Mathematica and Python are available.
Keywords: Model building, Feynman rules, Monte Carlo simulations.
PACS: 12.60.Cn, 12.60.Fr, 12.60.Jv.
Classification: 11.1, 11.6.

External routines: FeynRules 2.0 or higher, MadGraph5_aMC@NLO 2.2 or higher.

Nature of problem:
The program is a module for the FeynRules and MadGraph5_aMC@NLO packages that allows the computation of tree-level decay widths for arbitrary BSM models. The module consists of two parts:
  1. A FeynRules part, which allows one to compute analytically all tree-level two-body decay rates and to output them in the UFO format.
  2. A MadGraph5_aMC@NLO part, which allows the numerical computation of many-body decay rates.

Solution method:
  1. For the FeynRules part, the analytic expressions for the three-point vertices can be squared to obtain analytic formulas for two-body decay rates.
  2. For the MadGraph5_aMC@NLO part, MadGraph is used to generate all Feynman diagrams contributing to the decay, and diagrams that correspond to cascade decays are removed.

Restrictions:
Mathematica version 7 to 9. As the package is a module relying on FeynRules and MadGraph5_aMC@NLO all restrictions of these packages apply.

Running time:
The computation of the Feynman rules from a Lagrangian, as well as the computation of the decay rates, varies with the complexity of the model, and runs from a few seconds to several minutes. See Section 5 of the present manuscript for more information.