Solving cosmological problem in universal extra dimension models by introducing Dirac neutrino

Abstract

Universal extra dimension (UED) models with right-handed neutrinos are studied. The introduction of the neutrinos makes us possible not only to describe Dirac neutrino masses but also to solve the cosmological problem called the KK graviton problem. This problem is essentially caused by the late time decay of a KK photon into a KK graviton and a photon, and it distorts the spectrum of the cosmic microwave background or the diffuse photon. We point out that, once we introduce right-handed neutrinos to UED models, the KK photon decays dominantly into neutrinos and does not emit a photon. We also discuss sub-dominant modes with a photon in the decay quantitatively, and show that their branching ratios are so small that the spectra are not distorted.

Some discussions are added.

References in corpus (6)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Measurement of Neutrino Oscillation by the K2K Experiment
• A Measurement of Atmospheric Neutrino Flux Consistent with Tau Neutrino Appearance
• Precision electroweak constraints on Universal Extra Dimensions revisited
• Relic abundance of dark matter in the minimal universal extra dimension model
• Limit on the Neutrino Mass from the WMAP Three Year Data

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• Dark matter from late decays and the small-scale structure problems
• Gravitons and Dark Matter in Universal Extra Dimensions
• Relic abundance of dark matter in universal extra dimension models with right-handed neutrinos
• Productions of second Kaluza-Klein gauge bosons in the minimal universal extra dimension model at LHC
• Direct Detection of Kaluza-Klein Particles in Neutrino Telescopes
• Exclusive $B-->\pi {\ell }^{+}{\ell }^{-}$ and $B-->\rho {\ell }^{+}{\ell }^{-}$ Decays in the Universal Extra Dimension
• Radiative corrections to the lightest KK states in the T^2/(Z_2\times Z_2') orbifold
• The neutrino masses and the change of allowed parameter region in universal extra dimension models