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Related papers: Galactic diffuse gamma rays meet the PeV frontier

200 papers

We present a novel interpretation of the gamma-ray diffuse emission measured by H.E.S.S. in the Galactic Center (GC) region and the Galactic ridge. Our starting base is an updated analysis of PASS8 Fermi-LAT data, which allows to extend…

High Energy Astrophysical Phenomena · Physics 2017-07-27 D. Gaggero , D. Grasso , A. Marinelli , M. Taoso , A. Urbano , S. Ventura

The multi-TeV $\gamma$-rays from the Galactic Center (GC) have a cutoff at tens of TeV, whereas the diffuse emission has no such cutoff, which is regarded as an indication of PeV proton acceleration by the HESS experiment. It is important…

High Energy Astrophysical Phenomena · Physics 2017-04-12 Yi-Qing Guo , Zhen Tian , Zhen Wang , Hai-Jin Li , Tian-Lu Chen

We perform the first direct consistency check between the recently measured proton spectrum at the knee by Large High Altitude Air Shower Observatory (LHAASO) and the collaboration's own high-precision mapping of Galactic diffuse gamma-ray…

High Energy Astrophysical Phenomena · Physics 2025-09-03 Luis Enrique Espinosa Castro , Francesco Lorenzo Villante , Vittoria Vecchiotti , Carmelo Evoli , Giulia Pagliaroli

The secondary/primary cosmic-ray ratios and the diffuse backgrounds of gamma rays and neutrinos provide us with complementary information about the transport of Galactic cosmic rays~(CRs). We used the recent measurement of the diffuse gamma…

High Energy Astrophysical Phenomena · Physics 2025-06-13 Antonio Ambrosone , Carmelo Evoli , Benedikt Schroer , Pasquale Blasi

The diffuse Galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray…

High Energy Astrophysical Phenomena · Physics 2010-04-23 LAT Collaboration

The diffuse Galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray…

High Energy Astrophysical Phenomena · Physics 2019-08-13 T. A. Porter

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

The large-scale diffuse $\gamma-$ray flux observed by Fermi-LAT in the 1-100 GeV energy range, parameterized as $\propto E^{-\Gamma}$, has a spectral index $\Gamma$ that depends on the distance from the Galactic center. This feature, if…

High Energy Astrophysical Phenomena · Physics 2023-08-25 Vittoria Vecchiotti , Giulia Pagliaroli , Francesco Lorenzo Villante

The discovery of diffuse sub-PeV gamma-rays by the Tibet AS$_\gamma$ Collaboration promises to revolutionize our understanding of the high-energy astrophysical universe. It has been shown that these data broadly agree with prior theoretical…

High Energy Physics - Phenomenology · Physics 2022-02-22 Tarak Nath Maity , Akash Kumar Saha , Abhishek Dubey , Ranjan Laha

One of the main purposes in $\gamma$-ray astronomy is linked to the origin of Galactic cosmic rays. Unlike cosmic rays, $\gamma$ rays can be used to probe their production sites in the Galaxy and to find which type of astrophysical sources…

High Energy Astrophysical Phenomena · Physics 2024-12-18 J. Devin

The High-Energy Stereoscopic System (HESS) has detected diffuse TeV emission correlated with the distribution of molecular gas along the Ridge at the Galactic Center. Diffuse, non-thermal emission is also seen by the Fermi large area…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Oscar Macias , Chris Gordon , Roland Crocker , Stefano Profumo

The GALPROP model for cosmic-ray propagation is able to make explicit predictions for the distribution of galactic diffuse gamma-rays. We compare different propagation models with gamma-ray spectra measured by EGRET for various regions of…

Astrophysics · Physics 2009-11-11 Andrew W. Strong , Igor V. Moskalenko , Olaf Reimer

We present a study of the compatibility of some current models of the diffuse Galactic continuum gamma rays with EGRET data. A set of regions sampling the whole sky is chosen to provide a comprehensive range of tests. The range of EGRET…

Astrophysics · Physics 2011-05-05 A. W. Strong , I. V. Moskalenko , O. Reimer

Recent EGRET observations of the diffuse Galactic gamma-ray emission reveal a spectrum which is incompatible with the assumption that the cosmic ray spectra measured locally hold throughout the Galaxy: the spectrum above 1 GeV, where the…

Astrophysics · Physics 2009-11-07 I. Büsching , M. Pohl , R. Schlickeiser

Cosmic rays (CRs) are ubiquitous in the interstellar medium (ISM) of nearby galaxies, but many of their properties are not well-constrained. Gamma-ray observations provide a powerful tool in this respect, allowing us to constrain both the…

High Energy Astrophysical Phenomena · Physics 2023-07-19 Maria Werhahn , Philipp Girichidis , Christoph Pfrommer , Joseph Whittingham

Despite significant progress over more than 100 years, no accelerator has been unambiguously identified as the source of the locally measured flux of cosmic rays. High-energy electrons and positrons are of particular importance in the…

High Energy Astrophysical Phenomena · Physics 2018-11-30 Philipp Mertsch

Several observations from Fermi-LAT, up to few hundred GeV, and from H.E.S.S., up to $\sim$ 10 TeV, reported an intense $\gamma$-ray emission from the inner part of the Galactic plane. After the subtraction of point-like contributions, the…

High Energy Astrophysical Phenomena · Physics 2015-08-18 Daniele Gaggero , Dario Grasso , Antonio Marinelli , Alfredo Urbano , Mauro Valli

We employ the Monte Carlo particle collision code DPMJET3.04 to determine the multiplicity spectra of various secondary particles (in addition to $\pi^0$'s) with $\gamma$'s as the final decay state, that are produced in cosmic-ray ($p$'s…

Astrophysics · Physics 2007-06-13 C. -Y. Huang , M. Pohl , S. -E. Park , C. D. Daniels

The bulk of the diffuse galactic gamma-ray emission above a few tens of GeV has been conventionally ascribed to the decay of neutral pions produced in cosmic-ray interactions with interstellar matter. Cosmic-ray electrons may, however, make…

Astrophysics · Physics 2008-11-26 T. A. Porter , R. J. Protheroe

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…