Micromegas v_1.1 and v_1.0

MicrOMEGAs is a code written in  C for the calculation of the relic density in supersymmetry. It also calls some external FORTRAN functions. All annihilation processes as well as co-annihilation  processes are calculated exactly through a supersymmetric version of CompHEP. Co-annihilation processes include any type of slepton, squark, possible chargino or next to lightest neutralino as well as a gluino. By default the lightest neutralino is assumed to be the LSP, but the user can set any supersymmetric particle (not including Higgses!) to be the LSP, in particular a sneutrino.
All in all we have included about 2800 processes not counting charge conjugate states. Care is taken to deal with resonances (in particular for the Higgs resonances) and thresholds.  The present version uses FeynHiggs  to calculate the Higgs masses and Hdecay to include important QCD corrections to the width and partial widths of the Higgses. All Yukawa effects are included.  MicrOMEGAs can run by providing an unconstrained set of soft SUSY parameters at the electroweak scale.  In the present version, a mSUGRA model can be entered though the Isajet interface however any other RGE code can be used.  Many constraints can be applied, apart from the present direct limits on the masses of the supersymmetric particles, we provide routines for the muon g-2, b->s \gamma  and Delta rho.
We also provide a  sample file to be used for scans over a set of parameters as in mSUGRA. It is also possible to view the contributions of different channels to the relic density.

System requirements: C compiler, Fortran compiler, 500 kb of disk space for download, a minimum of 10Mb as working space.
Tested on: Dec Alpha, Silicon Graphics and Linux (Red Hat,Suse),   SunOS and HP-UX  .

Current version: micromegas_1.1.1 (23 August 2002)
   Changes from version 1.0:
(1st version: micromegas_1.0, december 2001)

Shortcomings to be included in next versions:

  • Although the program consists of about more 2800 processes (not counting charge conjugate related processes, etc), only tree-level processes are included. Missing are one-loop processes with 2\gamma and 2 gluons in the final state. For the relic density these are negligible.
  • Radiative corrections to neutralino and chargino masses are not implemented in the current version.
  • A new routine for b->s\gamma which includes NLO effects and large tgb effects will be included soon.

     Documentation here

      Install here