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arXiv · hep-ph/0303114

Chi**2 analysis of the minimal supergravity model including WMAP, g(mu)-2 and b -> s gamma constraints

Abstract

Recent results from the WMAP measurements of the cosmic background radiation yield very tight constraints on the relic density of supersymmetric cold dark matter. We combine the WMAP constraint with those from the anomalous magnetic moment of the muon and the b -> s gamma branching fraction in a chi^2 determination over the minimal supergravity model (mSUGRA) parameter space. The most favored region of mSUGRA parameter space for almost all tan(beta) values is the hyperbolic branch/focus point (HB/FP) region, with moderate to small values of superpotential Higgs mass |mu| and large GUT scale scalar mass m_0. These favored regions of mSUGRA parameter space can be probed by direct search experiments for supersymmetric dark matter. An exception to the HB/FP region can occur at very large tan(beta) with positive mu values, where wide regions allow resonance annihilation of neutralinos in the early universe.

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Howard Baer, Csaba Balazs. 2003-04-21. Chi**2 analysis of the minimal supergravity model including WMAP, g(mu)-2 and b -> s gamma constraints. https://doi.org/10.1088/1475-7516%2F2003%2F05%2F006

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