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Related papers: Evaluation of Models for Diffuse Continuum Gamma R…

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We have developed a model which aims to reproduce observational data of many kinds related to cosmic-ray (CR) origin and propagation: direct measurements of nuclei, antiprotons, electrons and positrons, gamma-rays, and synchrotron…

Astrophysics · Physics 2009-10-31 I. V. Moskalenko , A. W. Strong

Recent observations of the diffuse Galactic \gr emission (DGE) by the {\it Fermi} Large Area Telescope ({\it Fermi}-LAT) have shown significant deviations, above a few GeV until about 100 GeV, from DGE models that use the GALPROP code for…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Heinrich J. Voelk , Evgeny G. Berezhko

Most of the diffuse Galactic GeV gamma-ray emission is produced via collisions of cosmic ray (CR) protons with ISM protons. As such the observed spectra of the gamma-rays and the CRs should be strongly linked. Recent observations of…

High Energy Astrophysical Phenomena · Physics 2017-02-01 Lara Nava , David Benyamin , Tsvi Piran , Nir J. Shaviv

Recent observations of gamma-rays with the Fermi Large Area Telescope (LAT) in the direction of the inner Galaxy revealed a mysterious GeV excess. Its intensity is significantly above predictions of the standard model of cosmic rays (CRs)…

High Energy Astrophysical Phenomena · Physics 2021-08-10 Dmitry O. Chernyshov , Andrei E. Egorov , Vladimir A. Dogiel , Alexei V. Ivlev

Galactic diffuse continuum gamma-ray emission is intricately related to cosmic-ray physics and radio astronomy. We describe recent results from an approach which endeavours to take advantage of this. Information from cosmic-ray composition…

Astrophysics · Physics 2010-12-13 A. W. Strong , I. V. Moskalenko , O. Reimer

We show that the well-known discrepancy between the radial dependence of the Galactic cosmic ray (CR) nucleon distribution, as inferred most recently from EGRET observations of diffuse gamma-rays above 100 MeV, and of the most likely CR…

Astrophysics · Physics 2009-11-07 D. Breitschwerdt , V. A. Dogiel , H. J. Voelk

Inverse Compton scattering appears to play a more important role in the diffuse Galactic continuum emission than previously thought, from MeV to GeV energies. We compare models having a large inverse Compton component with EGRET data, and…

Astrophysics · Physics 2007-05-23 I. V. Moskalenko , A. W. Strong

Recently the Milagro experiment observed diffuse multi-TeV gamma-ray emission in the Cygnus region, which is significantly stronger than what predicted by the Galactic cosmic ray model. However, the sub-GeV observation by EGRET shows no…

Astrophysics · Physics 2009-06-23 Xiao-Jun Bi , Tian-Lu Chen , Yue Wang , Qiang Yuan

Here is reviewed our current understanding of Galactic and extragalactic diffuse gamma-ray emission. The spectrum of the extragalactic gamma-ray background above 30 MeV can be well described by a power law with photon index s=2.1. In the…

Astrophysics · Physics 2007-05-23 Martin Pohl

The standard approach to cosmic-ray (CR) propagation in the Galaxy is based on the assumption that local transport properties can be extrapolated to the whole CR confining volume. Such models tend to underestimate the gamma-ray flux above…

High Energy Astrophysical Phenomena · Physics 2015-05-06 Daniele Gaggero , Alfredo Urbano , Mauro Valli , Piero Ullio

Cosmic Rays (CRs) interact with the diffuse gas, radiation, and magnetic fields in the interstellar medium (ISM) to produce electromagnetic emissions that are a significant component of the all-sky flux across a broad wavelength range. The…

High Energy Astrophysical Phenomena · Physics 2022-11-30 P. D. Marinos , G. P. Rowell , T. A. Porter , G. Jóhannesson

Inverse Compton scattering appears to play a more important role in the diffuse Galactic continuum emission than previously thought, from MeV to GeV energies. We compare models having a large inverse Compton component with EGRET data, and…

Astrophysics · Physics 2007-05-23 I. V. Moskalenko , A. W. Strong

We simulate the neutrino and $\gamma$-ray emissions of the Galaxy which are originated from the hadronic scattering of cosmic rays (CR) with the interstellar medium (ISM). Rather than assuming a uniform CR density, we estimate the spatial…

Astrophysics · Physics 2010-10-27 Carmelo Evoli , Dario Grasso , Luca Maccione

The all-sky survey in high-energy gamma rays (E$>$30 MeV) carried out by the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma-Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray…

Astrophysics · Physics 2011-05-05 P. Sreekumar

The origin of the diffuse extragalactic, high-energy gamma-ray background (EGRB) filling the Universe remains unknown. The spectrum of this extragalactic radiation, as measured by the EGRET on-board CGRO, is well-fit by a power law across…

Astrophysics · Physics 2009-11-07 Caleb A. Scharf , Reshmi Mukherjee

Analyses of TeV-PeV cosmic ray (CR) diffusion around their sources usually assume either isotropic diffusion or anisotropic diffusion due to the regular Galactic magnetic field. We show that none of them are adequate on distances smaller…

High Energy Astrophysical Phenomena · Physics 2013-07-29 G. Giacinti , M. Kachelriess , D. V. Semikoz

We study the high latitude (|b|>10) diffuse gamma-ray emission in the Galaxy in light of the recently published data from the Fermi collaboration at energies between 100 MeV and 100 GeV. The unprecedented accuracy in these measurements…

High Energy Astrophysical Phenomena · Physics 2013-04-16 I. Cholis , M. Tavakoli , C. Evoli , L. Maccione , P. Ullio

The possible gamma-ray excess in the inner Galaxy and the Galactic center (GC) suggested by Fermi-LAT observations has triggered a large number of studies. It has been interpreted as a variety of different phenomena such as a signal from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Francesca Calore , Ilias Cholis , Christoph Weniger

Information on cosmic-ray (CR) composition comes from direct CR measurements while their distribution in the Galaxy is evaluated from observations of their associated diffuse emission in the range from radio to gamma rays. Even though the…

High Energy Astrophysical Phenomena · Physics 2019-03-06 Elena Orlando , Gudlaugur Johannesson , Igor V. Moskalenko , Troy A. Porter , Andrew Strong

Diffuse $\gamma$-ray emission produced by the interaction of cosmic-ray particles with matter and radiation in the Galaxy can be used to probe the distribution of cosmic rays and their sources in different regions of the Galaxy. With its…