SDECAY: a Fortran code for the decays of the supersymmetric particles in the MSSM

Abstract

We present the Fortran code SDECAY, which calculates the decay widths and branching ratios of all the supersymmetric particles in the Minimal Supersymmetric Standard Model, including higher order effects. Besides the usual two-body decays of sfermions and gauginos and the three-body decays of charginos, neutralinos and gluinos, we have also implemented the three-body decays of stops and sbottoms, and even the four-body decays of the stop; the important loop-induced decay modes are also included. The QCD corrections to the two-body decays involving strongly interacting particles and the dominant components of the electroweak corrections to all decay modes are implemented. Program summary Title of program: SDECAY Version 1.1a (March 2005) Catalogue identifier: ADVJ Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVJ Program obtainable: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions: none Computer for which the program is designed: Any with a Fortran77 system Operating systems under which the program has been tested: Linux, Unix Typical running time: A few seconds on modern personal computers and workstations Programming language used: Fortran77 No. of lines in distributed program, including test data, etc.: 59 621 No. of bytes in distributed program, including test data, etc.: 338 478 Distribution format: tar.gz Memory required to execute (with test data): 7.3 MB Distribution format: ASCII Nature of physical problem: Numerical calculation of the decay widths and branching ratios of supersymmetric particles in the Minimal Supersymmetric Standard Model (MSSM). The program calculates two-, three- and four-body decays and loop decays. It includes the SUSY-QCD corrections to two-body decays involving strongly interacting particles. The top-quark decays within the MSSM are evaluated as well. Method of solution: Two-dimensional numerical integration of the analytic formulae for the double differential decay widths of the three-body decays. The other decay widths are calculated analytically. Restrictions on the complexity of the problem: In the higher order decay modes the total decay widths of the virtually exchanged (s)particles are not included in their respective propagators. The higher order decays are calculated when the two-body decays are kinematically closed.