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Gamma Rays from Kaluza-Klein Dark Matter

Lars Bergstrom·Torsten Bringmann·Martin Eriksson·Michael Gustafsson
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Abstract

A TeV gamma-ray signal from the direction of the Galactic center (GC) has been detected by the H.E.S.S. experiment. Here, we investigate whether Kaluza-Klein (KK) dark matter annihilations near the GC can be the explanation. Including the contributions from internal bremsstrahlung as well as subsequent decays of quarks and tau leptons, we find a very flat gamma-ray spectrum which drops abruptly at the dark matter particle mass. For a KK mass of about 1 TeV, this gives a good fit to the H.E.S.S. data below 1 TeV. A similar model, with gauge coupling roughly three times as large and a particle mass of about 10 TeV, would give both the correct relic density and a photon spectrum that fits the complete range of data.

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Lars Bergstrom, Torsten Bringmann, Martin Eriksson, Michael Gustafsson. 2005-04-18. Gamma Rays from Kaluza-Klein Dark Matter. https://doi.org/10.1103/physrevlett.94.131301

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