English
Related papers

Related papers: Foreground Mismodeling and the Point Source Explan…

200 papers

Gamma-ray searches for new physics such as dark matter are often driven by investigating the composition of the extragalactic gamma-ray background (EGB). Classic approaches to EGB decomposition manifest in resolving individual point sources…

High Energy Astrophysical Phenomena · Physics 2018-10-31 Hannes-S. Zechlin , Silvia Manconi , Fiorenza Donato

The recent discovery of ten new dwarf galaxy candidates by the Dark Energy Survey (DES) and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) could increase the Fermi Gamma-Ray Space Telescope's sensitivity to…

High Energy Astrophysical Phenomena · Physics 2015-09-16 Dan Hooper , Tim Linden

The excess of $\gamma$ rays in the data measured by Fermi-LAT from the Galactic center region is one of the most intriguing mysteries in Astroparticle Physics. This Galactic center excess (GCE), has been measured with respect to different…

High Energy Astrophysical Phenomena · Physics 2021-05-27 Mattia Di Mauro

Precision measurements of the positron flux in cosmic ray have revealed an unexplained bump in the spectrum around $E\simeq 300\,\mathrm{GeV}$, not clearly attributable to known astrophysical processes. We propose annihilation of dark…

High Energy Physics - Phenomenology · Physics 2020-06-11 Anirban Das , Basudeb Dasgupta , Anupam Ray

One of the most prominent features of the $\gamma$-ray sky is the emission from our own Galaxy. The Galactic plane has been observed by Fermi-LAT in GeV and H.E.S.S. in TeV light. Fermi has modeled the Galactic emission as the sum of a…

High Energy Astrophysical Phenomena · Physics 2015-06-09 Ellis Owen , Christoph Deil , Axel Donath , Régis Terrier

There is evidence for an excess of gamma rays with $O({\rm GeV})$ energy coming from the Galactic Center in data from the Fermi Telescope. The spectrum of the excess is well fit by 30 GeV dark matter annihilating into a pair of $b$ quarks…

High Energy Physics - Phenomenology · Physics 2015-06-03 Seyda Ipek

Several groups of authors have analyzed Fermi LAT data in a region around the Galactic Center finding an unaccounted gamma-ray excess over diffuse backgrounds in the GeV energy range. It has been argued that it is difficult or even…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Jovana Petrovic , Pasquale D. Serpico , Gabrijela Zaharijas

The first data from the LHC Run-2 have shown a possible excess in diphoton events with invariant mass $\sim 750$ GeV, suggesting the existence of a new resonance which may decay dominantly into dark matter (DM) particles. We show in a…

High Energy Physics - Phenomenology · Physics 2016-06-15 Xian-Jun Huang , Wei-Hong Zhang , Yu-Feng Zhou

A spherical-symmetric gamma-ray emission from the central region of the Galaxy has been recently identified in Fermi-LAT data, and initially associated to dark matter particle annihilations. Guided by the evidence for a high gas density in…

High Energy Astrophysical Phenomena · Physics 2016-01-13 Daniele Gaggero , Marco Taoso , Alfredo Urbano , Mauro Valli , Piero Ullio

Recent results from the PAMELA, ATIC, PPB BETS and Fermi collaborations extend the energy range in the electron flux measurement up to unexplored energies in the hundred GeVs range confirming the bump starting at about 10GeV already…

High Energy Astrophysical Phenomena · Physics 2014-11-18 Ignacio Cernuda

Potential line emission at 111 and 129 GeV from 16 unassociated Fermi-LAT point sources has been reported recently by Su & Finkbeiner (2012c). Together with similar features seen by Fermi in a region near the Galactic Centre, the evidence…

High Energy Astrophysical Phenomena · Physics 2013-01-14 N. Mirabal

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…

High Energy Physics - Phenomenology · Physics 2012-10-31 Elmo Tempel , Andi Hektor , Martti Raidal

Several classes of astrophysical sources contribute to the approximately isotropic gamma-ray background measured by the Fermi Gamma-Ray Space Telescope. In this paper, we use Fermi's catalog of gamma-ray sources (along with corresponding…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Ilias Cholis , Dan Hooper , Samuel D. McDermott

Motivated by the gamma-ray excess observed from the region surrounding the Galactic Center, we explore particle dark matter models that could potentially account for the spectrum and normalization of this signal. Taking a model-independent…

High Energy Physics - Phenomenology · Physics 2015-06-04 Asher Berlin , Dan Hooper , Samuel D. McDermott

The isotropic gamma-ray background (IGRB), measured by the Fermi Large Area Telescope, is the result of several classes of extragalactic astrophysical sources. Those sources include blazars, start-forming galaxies and radio galaxies. Also,…

High Energy Astrophysical Phenomena · Physics 2024-08-22 Ilias Cholis , Iason Krommydas

Descriptions of the Galactic Center using Fermi gamma-ray data have so far modeled the Galactic Center Excess (GCE) as a template with fixed spatial morphology or as a linear combination of such templates. Although these templates are…

High Energy Astrophysical Phenomena · Physics 2024-10-30 Edward D. Ramirez , Yitian Sun , Matthew R. Buckley , Siddharth Mishra-Sharma , Tracy R. Slatyer

Motivated by the complex gamma-ray spectrum of the Galactic Center source now measured over five decades in energy, we revisit the issue of the role of dark matter annihilations in this interesting region. We reassess whether the emission…

High Energy Astrophysical Phenomena · Physics 2013-05-30 Alexander V. Belikov , Gabrijela Zaharijas , Joseph Silk

We search for spectral features in Fermi-LAT gamma-rays coming from regions corresponding to eighteen brightest nearby galaxy clusters determined by the magnitude of their signal line-of-site integrals. We observe a double peak-like excess…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Andi Hektor , Martti Raidal , Elmo Tempel

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…

High Energy Astrophysical Phenomena · Physics 2015-10-07 Timothy D. Brandt , Bence Kocsis

PAMELA's observation that the cosmic ray positron fraction increases rapidly with energy implies the presence of primary sources of energetic electron-positron pairs. Of particular interest is the possibility that dark matter annihilations…

High Energy Physics - Phenomenology · Physics 2014-11-20 Dan Hooper , Kathryn M. Zurek