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Related papers: New constraints on the cosmic mid-infrared backgro…

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We use the new results of the HEGRA detector on the TeV gamma-ray emission from MKN 501 to set upper limits on the energy density of the cosmic infrared background (CIRB). Contrary to previous interpretations of the gamma-ray spectrum of…

Astrophysics · Physics 2010-11-30 Todor Stanev , Alberto Franceschini

The energy spectrum of Mkn501 in the TeV energy regime, as measured by the HEGRA (High Energy Gamma Ray Astronomy) Cerenkov telescopes during its low state in 1995/96 and during a fraction of the 1997 outburst in the TeV energy regime, is…

Astrophysics · Physics 2009-10-30 B. Funk , N. Magnussen , H. Meyer , W. Rhode , S. Westerhoff , B. Wiebel-Sooth

The TeV and X-ray data obtained by the imaging Cherenkov telescope CAT and X-ray satellite BeppoSAX during the remarkable flare of Mkn 501 in April 16, 1997 are used to constrain the flux of the Cosmic Infrared Background (CIB) using…

Astrophysics · Physics 2007-05-23 J. Guy , C. Renault , F. A. Aharonian , M. Rivoal , J. -P. Tavernet

We present a semi-empirical model for the evolving far-infrared to ultraviolet diffuse background produced by stars in galaxies. The model is designed to reproduce the results of deep galaxy surveys, and therefore may be considered as a…

Astrophysics · Physics 2009-10-31 T. M. Kneiske , K. Mannheim , D. Hartmann

The recent observations of 50 TeV gamma radiation by HEGRA have the potential of determining the extragalactic flux of infrared radiation. The fact that radiation is observed in the range between 30 and 100 TeV sets an upper limit on the…

Astrophysics · Physics 2009-10-30 V. Berezinsky , Lars Bergström , H. R. Rubinstein

The Fermi gamma-ray space telescope has revolutionized our understanding of the cosmic gamma-ray background radiation in the GeV band. However, investigation on the cosmic TeV gamma-ray background radiation still remains sparse. Here, we…

High Energy Astrophysical Phenomena · Physics 2016-03-09 Yoshiyuki Inoue , Yasuyuki T. Tanaka

The recent HEGRA observations of the blazar Mkn 501 show strong curvature in the very high energy gamma-ray spectrum. Applying the gamma-ray opacity derived from an empirically based model of the intergalactic infrared background radiation…

With the arrival of powerful, ground-based gamma-ray detectors, we can now begin to seriously probe, via simultaneous X-ray/TeV observations, the origin of the gamma-ray emission in the blazars Mrk 421 and 501. If the synchrotron-Compton…

Astrophysics · Physics 2011-04-15 Paolo S. Coppi Felix A. Aharonian

Gamma rays from TeV blazars have been detected by ground-based experiments for more than two decades. We have collected the most extensive set of archival spectra from these sources in order to constrain the processes affecting gamma-ray…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 Jonathan Biteau , David A. Williams

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

We extend our previous model-independent determination of the intergalactic background light (IBL), based purely on galaxy survey data, out to a wavelength of 5 microns. Our approach enables us to constrain the range of photon densities,…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Sean T. Scully , Matthew A. Malkan , Floyd W. Stecker

The extragalactic background radiation produced by distant galaxies emitting in the far infrared limits the sensitivity of telescopes operating in this range due to confusion. We have constructed a model of the infrared background based on…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-19 S. V. Pilipenko , M. V. Tkachev , A. A. Ermash , T. I. Larchenkova , E. V. Mikheeva , V. N. Lukash

The spectra of very high energy gamma-radiation from distant extragalactic objects suffer significant deformations during the passage of primary gamma-rays through the intergalactic medium. The recently reported fluxes of diffuse infrared…

Astrophysics · Physics 2009-11-07 F. A. Aharonian , A. N. Timokhin , A. V. Plyasheshnikov

If galactic halos contain stellar remnants, the infra-red flux from the remnant progenitors would contribute to the opacity of multi-TeV gamma-rays. The multi-TeV gamma-ray horizon is established to be at a redshift z>0.034 by the…

Astrophysics · Physics 2009-10-31 David S. Graff , Katherine Freese , Terry Walker , Marc Pinsonneault

Recent experiments have measured the Galactic $\gamma$-ray diffuse emission up to PeV energies, opening a window to study acceleration of Galactic cosmic rays and their propagation up to the cosmic-ray knee. Furthermore, these observations…

High Energy Astrophysical Phenomena · Physics 2025-09-12 Manuel Rocamora , Pedro De La Torre Luque , Miguel A. Sánchez-Conde

In this paper, I will take a synoptic approach to determining the intergalactic infrared radiation field (IIRF). This approach draws on both the multi-TeV gamma-ray observations and the infrared background observations and relates them via…

Astrophysics · Physics 2007-05-23 F. W. Stecker

From considering the effect of gamma-gamma interactions on recently observed TeV gamma-ray spectra, improved limits are set to the density of extragalactic infrared (IR) photons which are robust and essentially model-independent. The…

For distant extragalactic sources of gamma-rays in the PeV energy range, interactions of the gamma rays with intergalactic diffuse radiation fields will initiate a pair cascade. Depending on the magnetic fields in the vicinity of the…

Astrophysics · Physics 2007-05-23 HEGRA Collaboration , F. Aharonian

We consider the implications of the recent determination of the universal infrared background for the propagation of photons up to 20 TeV from the active galaxy Markarian 501 as observed by HEGRA. At 20 TeV the mean free path for…

Astrophysics · Physics 2009-10-31 R. J. Protheroe , H. Meyer

We provide our estimates of the intensity of the gamma-ray emission with an energy near 0.1 TeV generated in inrergalactic space in the interactions of cosmic rays with background emissions. We assume that the cosmic ray sources are…

High Energy Astrophysical Phenomena · Physics 2017-08-30 A. V. Uryson
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