Item

Abstract

In this thesis we investigate to which extent dark matter direct detection experiments can probe the natural parameter space of the minimal supersymmetric standard model (MSSM).We therefore calculate the amount of tuning necessary to reach a certain point in the plane spanned by the neutralino mass and the spin-independent direct detection cross-section δ^SI by scanning an eleven dimensional low-energy input parameter space of the phenomenological MSSM. We allow in particular for a negative supersymmetric Higgs mass parameter μ. The simulated models respect all current experimental results including the evidence for the Higgs boson from the LHC and the new update of the XENON100 collaboration. For positive μ untuned solutions are mainly situated at the Z- and Higgs resonance since the recent XENON100 (2012) update has excluded most of the natural solutions in other regions. In these other regions, one can find a clear increase of the tuning level for smaller δ^SI. Untuned models that survived the new limit will be tested by XENON1t. When μ is negative cancellations may shift the untuned scenarios to smaller values of δ^SI, such that a negative μ is favored from a finetuning perspective. Many models may in this way even avoid detection by XENON1t. In this context we show that it is possible to respect the muon anomalous magnetic moment condition for a negative μ-term and positive gaugino masses and also present the probability distribution of our models.