Kaluza-Klein Dark Matter After Fermi

Understand

Kaluza-Klein photon in universal extra dimension models is one of the most attractive dark matter candidates as a weakly interacting massive particle.

• Having a characteristic split spectrum in split universal extra dimension the relic density of Kaluza-Klein photon with 900 GeV mass is in good agreement with the observed dark matter amount in our Universe.
• Interestingly Kaluza-Klein photon in the same mass range also provides excellent fits to the recently observed excesses in cosmic electron and positron fluxes.
• The amount of gamma-ray contributions, mostly from tau decays, can be significant around 300 GeV, thus can be observed or constrained by the forthcoming Fermi-LAT diffuse gamma-ray data.