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arXiv · hep-ph/0701229

On the Feasibility of a Stop NLSP in Gravitino Dark Matter Scenarios

J. L. Diaz-Cruz·John Ellis·Keith A. Olive·Yudi Santoso
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Abstract

We analyze the possibility that the lighter stop {\tilde t_1} could be the next-to-lightest supersymmetric particle (NLSP) in models where the gravitino is the lightest supersymmetric particle (LSP). We do not find any possibility for a stop NLSP in the constrained MSSM with universal input soft supersymmetry-breaking masses at the GUT scale (CMSSM), but do find small allowed regions in models with non-universal Higgs masses (NUHM). We discuss the cosmological evolution of stop hadrons. Most {\tilde t_1}qq `sbaryons' and the corresponding `antisbaryons' annihilate with conventional antibaryons and baryons into {\tilde t_1}{\bar q} `mesinos' and the corresponding `antimesinos', respectively, shortly after the quark-hadron transition in the early Universe, and most mesinos and antimesinos subsequently annihilate. As a result, insufficient metastable charged stop hadrons survive to alter Big Bang nucleosynthesis.

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J. L. Diaz-Cruz, John Ellis, Keith A. Olive, Yudi Santoso. 2007-01-26. On the Feasibility of a Stop NLSP in Gravitino Dark Matter Scenarios. https://doi.org/10.1088/1126-6708%2F2007%2F05%2F003

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