Constraints on the primordial power spectrum of small scales using the neutrino signals from the dark matter decay

Abstract

Many inflation theories predict that the primordial power spectrum is scale invariant. The amplitude of the power spectrum can be constrained by different observations such as the cosmic microwave background (CMB), Lyman-$\alpha$, large-scale structures and primordial black holes (PBHs). Although the constraints from the CMB are robust, the corresponding scales are very large ($10^{-4}<k<1\mathrm{Mp}{\mathrm{c}}^{-1}$). For small scales ($k>1\mathrm{Mp}{\mathrm{c}}^{-1}$), the research on the PBHs provides much weaker limits. Recently, ultracompact dark matter minihalos (UCMHs) was proposed and it was found that they could be used to constraint the small-scale primordial power spectrum. The limits obtained by the research on the UCMHs are much better than that of PBHs. Most of previous works focus on the dark matter annihilation within the UCMHs, but if the dark matter particles do not annihilate the decay is another important issue. In previous work~\cite{EPL}, we investigated the gamma-ray flux from the UCMHs due to the dark matter decay. In addition to these flux, the neutrinos are usually produced going with the gamma-ray photons especially for the lepton channels. In this work, we studied the neutrino flux from the UCMHs due to the dark matter decay. Finally, we got the constraints on the amplitude of primordial power spectrum of small scales.

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References in corpus (13)

• Decaying Dark Matter can explain the electron/positron excesses
• PAMELA data and leptonically decaying dark matter
• Generalised constraints on the curvature perturbation from primordial black holes
• Measurement of the atmospheric neutrino energy spectrum from 100 GeV to 400 TeV with IceCube
• Contraints on radiative dark-matter decay from the cosmic microwave background
• Minimally Parametric Power Spectrum Reconstruction from the Lyman-alpha Forest
• New Universal Local Feature in the Inflationary Perturbation Spectrum
• Dark Matter Candidates - Axions, Neutralinos, Gravitinos, and Axinos
• Small-scale clumps of dark matter
• Gamma-rays from ultracompact minihalos: potential constraints on the primordial curvature perturbation
• Muon Fluxes From Dark Matter Annihilation
• Probing dark matter models with neutrinos from the Galactic center
• Constraints on the ultracompact minihalos using neutrino signals from the gravitino dark matter decay

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• Tau neutrinos from ultracompact dark matter minihalos and constraints on the primordial curvature perturbations