Dark Matter in the MSSM Golden Region

Abstract

Dark matter is examined within the ``golden region'' of the Minimal Supersymmetric Standard Model. This region satisfies experimental constraints, including a lower bound on the Higgs mass of 114 GeV, and minimizes fine-tuning of the Z boson mass. Here we impose additional constraints (particularly due to experimental bounds on $b\to s \gamma$). Then we find the properties of the Dark Matter in this region. Neutralinos with a relic density that provides the amount of dark matter required by cosmological data are shown to consist of a predominant gaugino (rather than higgsino) fraction. In addition, the U(1)$_Y$ gaugino mass parameter must satisfy $M_1 < 300$ GeV.