@phdthesis{Staub2010,
  author    = {Staub, Florian},
  title     = {Considerations on supersymmetric Dark Matter beyond the MSSM},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-55343},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {The standard model (SM) of particle physics is for the last three decades a very successful description of the properties and interactions of all known elementary particles. Currently, it is again probed with the first collisions at the Large Hadron Collider (LHC). It is widely expected that new physics will be detected at the LHC and the SM has to be extended. The most exhaustive analyzed extension of the SM is supersymmetry (SUSY). SUSY can not only solve intrinsic problems of the SM like the hierarchy problem, but it also postulates new particles which might explain the nature of dark matter in the universe. The majority of all studies about dark matter in the framework of SUSY has focused on the minimal supersymmetric standard model (MSSM). The aim of this work is to consider scenarios beyond that scope. We consider two models which explain not only dark matter but also neutrino masses: the gravitino as dark matter in gauge mediated SUSY breaking (GMSB) with bilinear broken \$R\$-parity as well as different seesaw scenarios with the neutralino as dark matter candidate. Furthermore, we also study the next-to-minimal supersymmetric standard model (NMSSM) which solves the \(\mu\)-problem of the MSSM and discuss the properties of the neutralino as dark matter candidate. In case of \$R\$-parity violation, light gravitinos are often the only remaining candidate for dark matter in SUSY because of their very long life time. We reconsider the cosmological gravitino problem arising for this kind of models. It will be shown that the proposed solution for the overclosure of the universe by light gravitinos, namely the entropy production by decays of GMSB messenger, just works in a small subset of models and in fine-tuned regions of the parameter space. This is a consequence of two effects so far overlooked: the enhanced decay channels in massive vector bosons and the impact of charged messenger particles. Both aspects cause an interplay between different cosmological restrictions which lead to strong constraints on the parameters of GMSB models. Afterwards, a minimal supergravity (mSugra) scenario with additional chiral superfields at high energy scales is considered. These fields are arranged in complete \$SU(5)\$ multiplets in order to maintain gauge unification. The new fields generate a dimension 5 operator to explain neutrino data. Furthermore, they cause large differences in mass spectrum of MSSM fields because of the different evaluation of the renormalization group equations what changes also the properties of the lightest neutralino as dark matter candidate. We discuss the parameter space of all three possible seesaw scenarios with respect to dark matter and the impact on rare lepton flavor violating processes. As we will see, especially in seesaw type~III but also in type~II the mass spectrum and regions of parameter space consistent with dark matter differ significantly in comparison to a common mSugra scenario. Moreover, the experimental bounds, in particular of branching ratios like \(l_i \rightarrow l_j \gamma\), cause large constraints on the seesaw parameters.},
  subject      = {Supersymmetrie},
  language  = {en}
}