Related papers: GeV excess and phenomenological astrophysics model…
Annihilation of light dark matter of $m_{\rm DM} \approx (10-40)$ GeV into the Standard Model fermions has been suggested as a possible origin of the gamma-ray excess at GeV energies in the Fermi-LAT data. In this paper, we examine possible…
We attempt to simultaneously explain the recently observed 3.55 keV X-ray line in the analysis of XMM-Newton telescope data and the galactic center gamma ray excess observed by the Fermi gamma ray space telescope within an abelian gauge…
Astrophysical sources outside the Milky Way, such as active galactic nuclei and star-forming galaxies, leave their imprint on the gamma-ray sky as nearly isotropic emission referred to as the Extragalactic Gamma-Ray Background (EGB). While…
The center of the Milky Way is offering one of the most striking mystery in Astroparticle Physics. An excess of gamma rays (GCE) has been measured by several groups in the data collected by the Fermi Large Area Telescope (LAT) towards the…
Gamma-ray observations of the Galactic Center (GC) region provide some of the most sensitive measurements of annihilation signals from dark matter in the GeV-TeV mass range. We present the first results from 178 hours of VERITAS…
The GeV$-$TeV $\gamma-$ray line signal is the smoking gun signature of the dark matter annihilation or decay. The detection of such a signal is one of the main targets of some space-based telescopes, including Fermi-LAT and the upcoming…
Indirect searches for Dark Matter (DM) particles with mass in the MeV -- GeV scale have received significant attention lately. Pair-annihilations of such DM particles in the Galaxy can give rise to (at the same time) MeV to GeV…
In this paper, we suggest a new hypothesis for explaining the spectrum of the extragalactic MeV gamma-ray background as observed by COMPTEL and SMM. We propose that both the flux level and spectrum can be accounted for as a superposition of…
The recent high energy electron and positron flux observed by the DAMPE experiment indicates possible excess events near 1.4 TeV. Such an excess may be evidence of dark matter annihilations or decays in a dark matter subhalo that is located…
Diffuse Galactic gamma-ray emission is produced in interactions of cosmic rays with gas and ambient photon fields and thus provides us with an indirect measurement of cosmic rays in various locations in the Galaxy. The diffuse gamma-ray…
The direct measurements of the cosmic electron-positron spectrum around 1 TeV made by DAMPE have induced many theoretical speculations about possible excesses in the data above the standard astrophysical predictions that might have the dark…
The GLAST satellite mission will study the gamma ray sky with considerably greater exposure than its predecessor EGRET. In addition, it will be capable of measuring the arrival directions of gamma rays with much greater precision. These…
The GALPROP model for cosmic-ray (CR) propagation produces explicit predictions for the angular distribution of Galactic diffuse gamma rays. We compare our current models with EGRET spectra for various regions of the sky. This allows a…
The Galactic center gamma-ray excess (GCE) is a long-standing unsolved problem. One of candidate solutions, the dark matter (DM) annihilation, has been recently tested with other astrophysical observations, such as AMS-02 electron-positron…
If dark matter is unstable and the mass is within GeV-TeV regime, its decays produce high-energy photons that give contribution to the extragalactic gamma-ray background (EGRB). We constrain dark matter decay by analyzing the 50-month EGRB…
We show the existence of a statistically significant, robust detection of a gamma-ray source in the Milky Way Galactic Center that is consistent with a spatially extended signal using about 4 years of Fermi-LAT data. The gamma-ray flux is…
It has been recently proposed that the observed 511 keV emission from the Galactic bulge could be the product of very light (1-100 MeV) annihilating dark matter particles. Other possible explanations for this signal are associated with…
We present a potential test of the origin of the $\gamma$-ray Galactic Centre Excess (GCE). We demonstrate how gravitational microlensing by stellar mass objects along the line of sight to the Galactic Bulge can distinguish between the…
The flux of the diffuse gamma-ray background radiation (GBR) does not confirm that the excess in the flux of cosmic ray electrons between 300-800 GeV, which was measured locally with the ATIC instrument in balloon flights over Antartica, is…
We propose to test the dark matter (DM) interpretation of the positron excess observed by the PAMELA cosmic-ray (CR) detector through the identification of a Galactic diffuse gamma-ray component associated to DM-induced prompt and radiative…