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The Role of Wino Content in Neutralino Dark Matter

Andreas Birkedal-Hansen·Brent D. Nelson
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Abstract

We investigate the dark matter prospects of supersymmetric models with nonuniversal gaugino masses. We find that for very particular values of the ratio of soft supersymmetry-breaking gaugino masses, M2/M1, an enhanced coannihilation efficiency between the lightest chargino and the lightest neutralino occurs, allowing for scalars with masses well above the normally accepted limits for viable dark matter in the universal case. As a specific example, we investigate models of hidden sector gaugino condensation. These models exhibit high scalar masses, previously thought dangerous, and the requisite freedom in the ratio of gaugino masses. The cosmologically viable regions of parameter space are investigated, allowing very specific statements to be made about the content of the supersymmetry-breaking hidden sector.

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Andreas Birkedal-Hansen, Brent D. Nelson. 2001-02-07. The Role of Wino Content in Neutralino Dark Matter. https://doi.org/10.1103/physrevd.64.015008

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