相关论文: Accounting for the Unresolved X-ray Background wit…
We present a model where sterile neutrinos with rest masses in the range ~ keV to ~ MeV can be the dark matter and be consistent with all laboratory, cosmological, large-scale structure, as well as x-ray constraints. These sterile neutrinos…
We apply phase-space density considerations to obtain lower bounds on the mass of sterile neutrino as dark matter candidate. The bounds are different for non-resonant production, resonant production in the presence of lepton asymmetry and…
We propose a strategy of how to look for dark matter (DM) particles possessing a radiative decay channel and derive constraints on their parameters from observations of X-rays from our own Galaxy and its dwarf satellites. When applied to…
A sterile neutrino with mass of several keV can account for cosmological dark matter, as well as explain the observed velocities of pulsars. We show that X-rays produced by the decays of these relic sterile neutrinos can boost the…
We investigate the early Universe production of sterile neutrino Dark Matter by the decays of singlet scalars. All previous studies applied simplifying assumptions and/or studied the process only on the level of number densities, which…
We consider the possibility of constraining decaying dark matter by looking out through the Milky Way halo. Specifically we use Chandra blank sky observations to constrain the parameter space of sterile neutrinos. We find that a broad band…
Sterile neutrinos with a mass of a few keV can serve as cosmological warm dark matter. We study the production of keV sterile neutrinos in the early universe from the decay of a frozen-in scalar. Previous studies focused on heavy frozen-in…
The Standard Model of particle physics can be extended to include sterile (right-handed) neutrinos or axions to solve the dark matter problem. Depending upon the mixing angle between active and sterile neutrinos, the latter have the…
There exists an observed "desert" spanning six orders of magnitude between O(0.5) eV and O(0.5) MeV in the fermion mass spectrum. We argue that it might accommodate one or more keV sterile neutrinos as a natural candidate for warm dark…
Sterile neutrinos with masses in the keV range are well-motivated extensions to the Standard Model that could explain the observed neutrino masses while also making up the dark matter (DM) of the Universe. If sterile neutrinos are DM then…
The exact seesaw relation in a type-I seesaw framework puts constraints on the relations between active and sterile neutrino sectors in terms of their masses and mixing angles. In such a setup, we employ a model-independent approach to…
Elementary keV sterile Dirac neutrinos can be a natural ingredient of the composite neutrino scenario. For a certain class of composite neutrino theories, these sterile neutrinos naturally have the appropriate mixing angles to be resonantly…
We review the status of sterile neutrino dark matter and discuss astrophysical and cosmological bounds on its properties as well as future prospects for its experimental searches. We argue that if sterile neutrinos are the dominant fraction…
We discuss under what circumstances a signal in upcoming laboratory searches for keV-scale sterile neutrinos would be compatible with those particles being a sizable part or all of dark matter. In the parameter space that will be…
The role of the sterile neutrinos to the r-process nucleosynthesis in supernova explosions is studied. Previously it has been argued that a large part of neutrino mixing can be excluded if the supernovae are the origin of the heavy…
Sterile neutrinos with masses at the $\mathrm{keV}$ scale and mixing to the active neutrinos offer an elegant explanation of the observed dark matter (DM) density. However, the very same mixing inevitably leads to radiative photon emission…
We present two complementary NuSTAR x-ray searches for keV-scale dark matter decaying to mono-energetic photons in the Milky Way halo. In the first, we utilize the known intensity pattern of unfocused stray light across the detector planes…
The sterile neutrino solutions to different irregular results and observations in neutrino physics are studied. It is pointed out that introducing sterile neutrinos helps to solve simultaneously the observed anomalies. It is argued that…
We compute the cosmological background radiation of gamma rays and neutrinos due to neutralino annihilation in evolving dark matter halos, assuming the observed dark matter is comprised of thermally excited neutralinos in the MSSM. The…
The fraction of the hard X-ray background (XRB) resolved into individual sources by the deep Chandra and XMM-Newton surveys strongly depends on the adopted energy range and decreases with increasing energy. As a consequence, the nature of…