相关论文: Constraining Extended Gamma-ray Emission from Gala…
Emission of AGNs and neutral pion decay - are the two most natural mechanisms, that could make a galaxy cluster be a source of gamma-rays in the GeV regime. We revisited this problem by using 52.5-month FERMI-LAT data above 10 GeV and…
(Abridged) We study the predictions of various annihilating Dark Matter (DM) models in order to interpret the origin of non-thermal phenomena in galaxy clusters. We consider three neutralino DM models with light (9 GeV), intermediate (60…
According to high resolution cold dark matter (CDM) simulations, large virialized halos are formed through the constant merging of smaller halos formed at earlier times. In particular, the halo of our Galaxy may have hundreds of dark matter…
We present a search for gamma-ray emission from the direction of the newly discovered dwarf galaxy Reticulum II. Using Fermi-LAT data, we detect a signal that exceeds expected backgrounds between ~2-10 GeV and is consistent with…
Cosmological $N$-body simulations show that Milky Way-sized galaxies harbor a population of unmerged dark matter subhalos. These subhalos could shine in gamma-rays and be eventually detected in gamma-ray surveys as unidentified sources. We…
The Fermi satellite has recently detected gamma ray emission from the central regions of our Galaxy. This may be evidence for dark matter particles, a major component of the standard cosmological model, annihilating to produce high-energy…
We present a detailed investigation of the $\gamma$-ray emission in the vicinity of the supernova remnant (SNR) W28 (G6.4$-$0.1) observed by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope. We detected significant…
We discuss the possibility of identification of point-like gamma-ray sources (PGS) with small scale dark matter (DM) clumps in our Galaxy. Gamma-rays are supposed to originate from annihilation of DM particles in the clumps, where…
Employing Fermi-LAT gamma ray observations, several independent groups have found excess extended gamma ray emission at the Galactic center (GC). Both, annihilating dark matter (DM) or a population of $\sim 10^3$ unresolved millisecond…
Recent claims of a line in the Fermi-LAT photon spectrum at 130 GeV are suggestive of dark matter annihilation in the galactic center and other dark matter-dominated regions. If the Fermi feature is indeed due to dark matter annihilation,…
We present the first measurement of the cross-correlation of weak gravitational lensing and the extragalactic gamma-ray background emission using data from the Canada-France-Hawaii Lensing Survey and the Fermi Large Area Telescope. The…
The nearby Large Magellanic Cloud (LMC) provides a rare opportunity of a spatially resolved view of an external star-forming galaxy in gamma-rays. The LMC was detected at 0.1-100GeV as an extended source with CGRO/EGRET and using early…
Galaxy clusters are the most massive gravitationally bound structures in the Universe. Even if clusters are nearly virialized structures, they undergo merging processes, creating merging shocks, and suffer from feedback from galaxies and…
We estimate the spatial locations of sources of the the observed features in the Fermi-LAT photon spectrum at $E_\gamma=110$ and $E_\gamma=130$ GeV. We determine whether they are consistent with emission from a single source, as would be…
Past studies have identified a spatially extended excess of $\sim$1-3 GeV gamma rays from the region surrounding the Galactic Center, consistent with the emission expected from annihilating dark matter. We revisit and scrutinize this signal…
The Galactic center $\gamma$-ray excess, detected by the Fermi-LAT, is a very attractive tentative signal from dark matter annihilation. Searching for associated synchrotron emissions can test the dark matter interpretation for this excess.…
We present studies of the Extreme Ultraviolet (EUV) emission in the Fornax cluster of galaxies; a relatively nearby well-studied cluster with X-ray emitting cluster gas and a very large radio source. We examine both the large-scale (~size…
The distribution of dark matter in the Galaxy, according to state-of-the-art simulations, shows not only a smooth halo component but also a rich substructure where a hierarchy of dark matter subhalos of different masses is found. We present…
During its first year of data taking, the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope has collected a large sample of high-energy cosmic-ray electrons and positrons (CREs). We present the results of a directional…
We use data from the Large Area Telescope onboard the Fermi gamma-ray space telescope (Fermi-LAT) to analyze the faint gamma-ray source located at the center of the Sagittarius (Sgr) dwarf spheroidal galaxy. In the 4FGL-DR3 catalog, this…