MicrOMEGAs: Version 1.3

Abstract

We present the latest version of micrOMEGAs, a code that calculates the relic density of the lightest supersymmetric particle (LSP) in the minimal supersymmetric standard model (MSSM). All tree-level processes for the annihilation of the LSP are included as well as all possible coannihilation processes with neutralinos, charginos, sleptons, squarks and gluinos. The cross-sections extracted from CalcHEP are calculated exactly using loop-corrected masses and mixings as specified in the SUSY Les Houches Accord. Relativistic formulae for the thermal average are used and care is taken to handle poles and thresholds by adopting specific integration routines. The input parameters can be either the soft SUSY parameters in a general MSSM or the parameters of a SUGRA model specified at the GUT scale. In the latter case, a link with Suspect, SOFTSUSY, Spheno and Isajet allows one to calculate the supersymmetric spectrum, Higgs masses, as well as mixing matrices. Higher-order corrections to Higgs couplings to quark pairs including QCD as well as some SUSY corrections ( Δ m b ) are implemented. Routines calculating ( g − 2 ) μ , b → s γ and B s → μ + μ − are also included. In particular the b → s γ routine includes an improved NLO for the SM and the charged Higgs while the SUSY large tan β effects beyond leading-order are included. This new version also provides cross-sections for any 2 → 2 process as well as partial decay widths for two-body final states in the MSSM allowing for easy simulation at colliders. Program summary Program title:micrOMEGAs1.3 Catalogue identifier:ADQR_v1_3 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADQR_v1_3 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions:none Computer:PC, Alpha, Silicon graphics, Sun Programming language:C and Fortran Operating system:UNIX (Linux, OSF1, IRIX64, SunOS) RAM:20 MB depending on the number of processes required No of lines in distributed program, including test data, etc.:78 314 No. of bytes in distributed program, including test data, etc.:703 112 Distribution format:tar.gz Number of processors used:1 External routines/libraries:Library of Fortran functions, for example, -lg2c (platform dependent) Catalogue identifier of previous version:ADQR Journal reference of previous version:Comput. Phys. Comm. 149 (2002) 103 Does the new version supersede the previous version?:yes Nature of problem:Calculation of the relic density of the lightest supersymmetric particle in the MSSM. Solution method:In numerically solving the evolution equation for the density of dark matter, relativistic formulae for the thermal average are used. All tree-level processes for annihilation and coannihilation of SUSY particles are included. The cross-sections for all processes are calculated exactly with CalcHEP. Higher-order corrections to Higgs masses and Higgs couplings to quark pairs including QCD as well as some SUSY corrections are implemented. The input parameters can be either the soft SUSY parameters in a general MSSM or the parameters of a SUGRA model specified at the GUT scale. In the latter case, a link with Suspect, SOFTSUSY, Spheno and Isajet allows to calculate the supersymmetric spectrum, Higgs masses, as well as mixing matrices. Reasons for the new version:This new version contains a more accurate calculation of the relic density of dark matter as well as many new features both for interface with codes that calculate the supersymmetric spectrum as well as for computation of cross-sections and decays relevant for collider physics. Summary of revisions: • Interface with the main codes to calculate the supersymmetric spectrum: Suspect, Isajet, Spheno and SOFTSUSY in models defined at some high scale. • Includes loop corrected sparticle masses and mixing matrices. • Includes loop-corrected Higgs masses and widths. QCD corrections to the Higgs couplings to fermion pairs are included as well as, via an effective Lagrangian, the Δ m b correction relevant at large tan β . • Provides exact numerical solution of the Boltzmann equation by Runge–Kutta. • Outputs the relative contribution of each channel to 1 / Ω . • Computes cross-sections for any 2 → 2 process at the parton level. • Calculates decay widths for all particles at tree-level including all 1 → 2 decay modes. • Calculates constraints on MSSM: B s → μ + μ − and NLO corrections to b → s γ . Unusual features:Depending on the parameters of the model, the program generates additional new code for matrix elements, compiles it and loads it dynamically. Running time:0.2 sec.