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Related papers: Fine structure in the gamma-ray sky

200 papers

The extragalactic background (EGB) of diffuse gamma rays can be determined by subtracting the Galactic contribution from the data. This requires a Galactic model (GM) and we include for the first time the contribution of dark matter…

Astrophysics · Physics 2009-11-13 W. de Boer , A. Nordt , C. Sander , V. Zhukov

As of early 2009, latest results on Galactic sources (mainly shell-type and plerionic supernova remnants), as observed in the very-high-energy gamma-ray domain, are reviewed. A particular attention is given to those obtained with the…

High Energy Astrophysical Phenomena · Physics 2009-05-11 Matthieu Renaud

Hot ionized interstellar medium interlinks star formation and stellar feedback processes, redistributing energy, momentum, and material throughout galaxies. We use X-ray data from $Chandra$ to extract the hot gas emission from 78 of the…

Astrophysics of Galaxies · Physics 2025-09-01 Chunyi Zhang , Junfeng Wang

Many star-forming galaxies and those hosting active galactic nuclei (AGN) show evidence of massive outflows of material in a variety of phases including ionized, neutral atomic, and molecular. Molecular outflows in particular have been the…

High Energy Astrophysical Phenomena · Physics 2023-02-15 Alex McDaniel , Marco Ajello , Chris Karwin

Galactic diffuse emissions in gamma rays and neutrinos arise from interactions of cosmic rays with the interstellar medium and probe the cosmic-ray intensity away from the Solar system. Model predictions for those are influenced by the…

High Energy Astrophysical Phenomena · Physics 2026-03-11 Anton Stall , Philipp Mertsch

Recently, a spatially extended excess of gamma rays collected by the Fermi-LAT from the inner region of the Milky Way has been detected by different groups and with increasingly sophisticated techniques. Yet, any final conclusion about the…

High Energy Astrophysical Phenomena · Physics 2015-02-11 Francesca Calore , Ilias Cholis , Christoph Weniger

The nature of the GeV gamma-ray Galactic center excess (GCE) in the data of Fermi-Large Area Telescope (LAT) is still to be unveiled. We present a new analysis of the inner Galaxy Fermi-LAT data at energies above 10 GeV, based on an…

High Energy Astrophysical Phenomena · Physics 2024-05-27 Silvia Manconi , Francesca Calore , Fiorenza Donato

Based on the diffusion-halo model for cosmic-ray (CR) propagation, including stochastic reacceleration due to collisions with hydromagnetic turbulence, we study the behavior of the electron component and the diffuse $\gamma$-rays…

High Energy Astrophysical Phenomena · Physics 2011-01-27 T. Shibata , T. Ishikawa , S. Sekiguchi

In the course of its operation, the EGRET experiment detected high-energy gamma ray sources at energies above 100 MeV over the whole sky. In this communication, we search for large-scale anisotropy patterns among the catalogued EGRET…

Astrophysics · Physics 2007-05-23 Luis Anchordoqui , Thomas McCauley , Thomas Paul , Olaf Reimer , Diego F. Torres

We calculate the absorption of 10-500 GeV gamma-rays at high redshifts. This calculation requires the determination of the high-redshift evolution of the intergalactic starlight photon field, including its IR-UV spectral energy…

Astrophysics · Physics 2008-11-26 M. H. Salamon , F. W. Stecker

The detection of diffuse radio emission associated with clusters of galaxies indicates populations of relativistic leptons infusing the intracluster medium. Those electrons and positrons are either injected into and accelerated directly in…

High Energy Astrophysical Phenomena · Physics 2015-05-19 M. Ackermann et al.

We study the diffusive escape of cosmic rays from a central source inside a galaxy cluster to obtain the suppression in the outgoing flux appearing when the confinement times get comparable or larger than the age of the sources. We also…

High Energy Astrophysical Phenomena · Physics 2017-02-06 Diego Harari , Silvia Mollerach , Esteban Roulet

In almost any scenario for 'cosmological' gamma-ray bursts (and in many models where they originate in our own Galaxy), the initial energy density is so large that the resulting relativistic plasma expands with $v\sim c$ producing a blast…

Astrophysics · Physics 2009-10-22 P. Meszaros , M. J. Rees

Recent direct measurements of Galactic cosmic ray spectra by balloon/space-borne detectors reveal spectral hardenings of all major nucleus species at rigidities of a few hundred GV. The all-sky diffuse gamma-ray emissions measured by the…

High Energy Astrophysical Phenomena · Physics 2018-03-21 Yi-Qing Guo , Qiang Yuan

We calculate the flux of radio, hard X-ray and UV radiation from clusters of galaxies as produced by synchrotron emission and Inverse Compton Scattering of electrons generated as secondaries in cosmic ray interactions in the intracluster…

Astrophysics · Physics 2011-08-09 P. Blasi , S. Colafrancesco

High-energy gamma rays of interstellar origin are produced by the interaction of cosmic-ray (CR) particles with the diffuse gas and radiation fields in the Galaxy. The main features of this emission are well understood and are reproduced by…

High Energy Astrophysical Phenomena · Physics 2017-09-06 Troy A. Porter , Gudlaugur Johannesson , Igor V. Moskalenko

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

An extensive program for the calculation of galactic cosmic-ray propagation has been developed. This is a continuation of the work described in Strong & Youssefi (1995). The main motivation for developing this code is the prediction of…

Astrophysics · Physics 2009-10-30 A. W. Strong , I. V. Moskalenko

Star-forming galaxies which are too faint to be detected individually produce intensity fluctuations in the cosmic background light. This contribution needs to be taken into account as a foreground when using the primordial signal to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Han-Seek Kim , C. G. Lacey , S. Cole , C. M. Baugh , C. S. Frenk , G. Efstathiou

Recently, two nearby prominent starburst galaxies, M82 and NGC253, have been detected as point-like sources with gamma-ray telescopes at TeV energies [1] [2]. It has been claimed that these detections show that the cosmic ray intensity in…

High Energy Astrophysical Phenomena · Physics 2010-10-13 O. Tibolla , K. Mannheim , D. Elsässer