相关论文: Multiple Gamma Lines from Semi-Annihilation
We introduce a novel dark matter scenario where the visible sector and the dark sector share a common asymmetry. The two sectors are connected through an unstable mediator with baryon number one, allowing the standard model baryon asymmetry…
There is evidence for a spectral line at $E_\gamma\approx 130$ GeV in the Fermi-LAT data that can be explained as dark mater particles annihilating into photons. We review a well known dark matter model that consists in a singlet Dirac…
We analyze publicly available Fermi-LAT high-energy gamma-ray data and confirm the existence of clear spectral feature peaked at E=130GeV. Scanning over the Galaxy we identify several disconnected regions where the observed excess…
Dark matter annihilation into photons in our galaxy would constitute an exciting indirect signal of its existence, as underscored by tentative evidence for 130 GeV dark matter in Fermi/LAT data. Models that give a large annihilation cross…
Dark matter (DM) particle annihilation or decay can produce monochromatic $\gamma$-rays readily distinguishable from astrophysical sources. $\gamma$-ray line limits from 30 GeV to 200 GeV obtained from 11 months of Fermi Large Area Space…
Semi-annihilation is a generic feature of dark matter theories with symmetries larger than Z_2. We explore a model based on a Z_4-symmetric dark sector comprised of a scalar singlet and a "wino"-like fermion SU(2)_L triplet. This is the…
Dark matter annihilation into charged particles is necessarily accompanied by gamma rays, produced via radiative corrections. Internal bremsstrahlung from the final state particles can produce hard gamma rays up to the dark matter mass,…
Excess Fermi GeV emission around the Galactic Centre has been interpreted as a possible signature of annihilating dark matter. Here we analyse three aspects of this claim: its spectral cutoff, the correlation between the spectral shape of…
Weakly interacting massive particles, as a major candidate of dark matter (DM), may directly annihilate or decay into high-energy photons, producing monochromatic spectral lines in the gamma-ray band. These spectral lines, if detected, are…
In the energy range from few TeV to 25 TeV, upper bounds on the dark matter decay rate into high energy monochromatic neutrinos have recently become comparable to those on monochromatic gamma-ray lines. This implies clear possibilities of a…
Recent evidence for one or more gamma-ray lines at ~ 130 GeV in the Fermi-LAT data from the Galactic Center has been interpreted as a hint for dark matter annihilation to Z{\gamma} or H{\gamma} with an annihilation cross section, <\sigma v>…
Both the robust INTEGRAL 511 keV gamma-ray line and the recent tentative hint of the 135 GeV gamma-ray line from Fermi-LAT have similar signal morphologies, and may be produced from the same dark matter annihilation. Motivated by this…
Recently, tentative evidence for an excess of gamma rays at energies around 130 GeV has been reported from analyses of data from the Fermi Large Area Telescope (LAT). The excess is potentially of great interest, as it could be associated…
The center of the Milky Way is predicted to be the brightest region of gamma-rays generated by self-annihilating dark matter particles. Excess emission about the Galactic center above predictions made for standard astrophysical processes…
We describe cosmic gamma-ray and neutrino signals of dark matter annihilation, explaining how the complementarity of these signals provides additional information that, if observable, can enlighten the particle nature of dark matter. This…
As the largest gravitationally bound objects in the Universe, galaxy clusters have provided the first piece of evidence for the presence of dark matter and may be suitable targets for indirect dark matter searches. Among various signals,…
Dark matter in the Milky Way may annihilate directly into gamma rays, producing a monoenergetic spectral line. Therefore, detecting such a signature would be strong evidence for dark matter annihilation or decay. We search for spectral…
It was recently reported that there may exist monochromatic $\gamma$-ray emission at $\sim 130$ GeV from the Galactic center in the Fermi Large Area Telescope data, which might be related with dark matter (DM) annihilation. In this work we…
A commonly encountered obstacle in indirect searches for galactic dark matter is how to disentangle possible signals from astrophysical backgrounds. Given that such signals are most likely subdominant, the search for pronounced spectral…
Semi-annihilation is a generic feature of particle dark matter that is most easily probed by cosmic ray experiments. We explore models where the semi-annihilation cross section is enhanced at late times and low temperatures by the presence…