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arXiv · hep-ph/0408120

Neutralino Relic Density in a Supersymmetric U(1)' Model

Vernon Barger·Chung Kao·Paul Langacker·Hye-Sung Lee
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Abstract

We study properties of the lightest neutralino (χ) and calculate its cosmological relic density in a supersymmetric U(1)' model with a secluded U(1)' breaking sector (the S-model). The lightest neutralino mass is smaller than in the minimal supersymmetric standard model; for instance, m_χ< 100 GeV in the limit that the U(1)' gaugino mass is large compared to the electroweak scale. We find that the Z-χ-χcoupling can be enhanced due to the singlino components in the extended neutralino sector. Neutralino annihilation through the Z-resonance then reproduces the measured cold dark matter density over broad regions of the model parameter space.

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Vernon Barger, Chung Kao, Paul Langacker, Hye-Sung Lee. 2004-09-02. Neutralino Relic Density in a Supersymmetric U(1)' Model. https://doi.org/10.1016/j.physletb.2004.08.070

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