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arXiv · 1012.2577

Dark matter in UED : the role of the second KK level

G. Belanger·M. Kakizaki·A. Pukhov
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Abstract

We perform a complete calculation of the relic abundance of the KK-photon LKP in the universal extra dimension model including all coannihilation channels and all resonances. We show that the production of level 2 particles which decay dominantly into SM particles contribute significantly to coannihilation processes involving level 1 KK-leptons. As a result the preferred dark matter scale is increased to $R^{-1}=1.3$~TeV. A dark matter candidate at or below the TeV scale can only be found in the non-minimal model by reducing the mass splittings between the KK-particles and the LKP. The LKP nucleon scattering cross section is typically small, $\sigma < 10^{-10}$~pb, unless the KK-quarks are nearly degenerate with the LKP.

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G. Belanger, M. Kakizaki, A. Pukhov. 2010-12-12. Dark matter in UED : the role of the second KK level. https://doi.org/10.1088/1475-7516/2011/02/009

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