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Related papers: A strict lower-limit EBL: Applications on gamma-ra…

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Recent progress in very high energy (VHE, E >100 GeV) $\gamma$-ray observations, together with advances in the extragalactic background light (EBL) modelling, allows to search for new phenomena such as $\gamma$-axion-like particle ($\gamma…

High Energy Astrophysical Phenomena · Physics 2017-05-16 T. A. Dzhatdoev

The all-sky surveys in gamma-rays by the imaging Compton telescope (COMPTEL) and the Energetic Gamma Ray Experiment Telescope (EGRET) on board the Compton Gamma Ray Observatory for the first time allows detailed studies of the extragalactic…

Astrophysics · Physics 2009-10-30 P. Sreekumar , F. W. Stecker , S. C. Kappadath

The extragalactic background light (EBL) is the relic emission of all processes of structure formation in the Universe. About half of this background, called the Cosmic Infrared Background (CIB) is emitted in the 8-1000 microns range, and…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-10 Matthieu Béthermin , Hervé Dole

The extragalactic $\gamma$-ray background (EGB) arises from the accumulation of $\gamma$-ray emissions from resolved and unresolved extragalactic sources as well as diffuse processes. It is important to study the statistical properties of…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 Masato Shirasaki , Oscar Macias , Shunsaku Horiuchi , Naoki Yoshida , Chien-Hsiu Lee , Atsushi J. Nishizawa

Very-high-energy (VHE, E \gtrsim 100 GeV) gamma rays emitted by extragalactic sources, such as blazars, initiate electromagnetic cascades in the intergalactic medium. The cascade photons arrive at the earth with angular and temporal…

High Energy Astrophysical Phenomena · Physics 2011-06-17 H. Huan , T. Weisgarber , T. Arlen , S. P. Wakely

We briefly review contemporary extragalactic {\gamma}-ray propagation models. It is shown that the Extragalactic Magnetic Field (EGMF) strength and structure are poorly known. Strict lower limits on the EGMF strength in voids are of order…

High Energy Astrophysical Phenomena · Physics 2017-04-05 T. A. Dzhatdoev , E. V. Khalikov , A. P. Kircheva , A. A. Lyukshin

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

This work investigates the impact of the extragalactic background light fluctuations on very high energy $\gamma$-ray spectra from distant Quasars. We calculate the extragalactic background light spectral energy distribution using a model…

High Energy Astrophysical Phenomena · Physics 2016-03-02 Ayman M. Kudoda , Andreas Faltenbacher

Axion-like particles (ALPs) provide a feasible explanation for the observed lower TeV opacity of the Universe. If the anomaly TeV transparency is caused by ALPs, then the fluxes of distant extragalactic sources will be enhanced at photon…

High Energy Astrophysical Phenomena · Physics 2021-11-17 Yun-Feng Liang , Xing-Fu Zhang , Ji-Gui Cheng , Hou-Dun Zeng , Yi-Zhong Fan , En-Wei Liang

This review covers the measurements related to the extragalactic background light (EBL) intensity from gamma-rays to radio in the electromagnetic spectrum over 20 decades in the wavelength. The cosmic microwave background (CMB) remains the…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-11 Asantha Cooray

We combine wide and deep galaxy number-count data from GAMA, COSMOS/G10, HST ERS, HST UVUDF and various near-, mid- and far- IR datasets from ESO, Spitzer and Herschel. The combined data range from the far-UV (0.15microns) to far-IR…

We describe a new method for measuring the extragalactic background light (EBL) through the detection of $\gamma$-ray inverse Compton (IC) emission due to scattering of the EBL photons off relativistic electrons in the lobes of radio…

TeV gamma rays emitted by GRBs are converted into electron-positron pairs via interactions with the extragalactic infrared radiation fields. In turn the pairs produced, whose trajectories are randomized by magnetic fields, will inverse…

Astrophysics · Physics 2011-04-11 S. Casanova , B. L. Dingus , Bing Zhang

Most blazars are known to be hosted in giant elliptic galaxies, but their cluster environments have not been thoroughly investigated. Cluster environments may contain radiation fields of low-energy photons created by nearby galaxies and/or…

High Energy Astrophysical Phenomena · Physics 2014-12-17 Iurii Sushch , Markus Böttcher

Very high energy (VHE) gamma-rays undergo pair production with low energy photons of background radiation fields. This leads to an attenuation of the primary gamma-ray flux of extragalactic sources in the interaction with the extragalactic…

High Energy Astrophysical Phenomena · Physics 2014-10-08 Manuel Meyer , Dieter Horns

Recent observations with the low threshold Cherenkov telescopes proved that sub-TeV gamma-rays are able to arrive from active galaxies at relatively large distances in spite of expected severe absorption in the extragalactic background…

Astrophysics · Physics 2013-06-21 J. Sitarek , W. Bednarek

This paper represents a step toward constraining galaxy formation models via TeV gamm a ray observations. We use semi-analytic models of galaxy formation to predict a spectral distribution for the intergalactic infrared photon field, which…

Astrophysics · Physics 2009-10-31 L. M. Boone , J. S. Bullock , J. R. Primack , D. A. Williams

The spectral shape of the unresolved emission from different classes of gamma-ray emitters can be used to disentangle the contributions from these populations to the extragalactic gamma-ray background (EGRB). We present a calculation of the…

Astrophysics · Physics 2010-11-11 Vasiliki Pavlidou , Tonia M. Venters

Several recent papers claim the detection of a near infrared Extragalactic Background Light (EBL) intensity at 1.25 - 4 um that exceeds the integrated light of galaxies by factors of >3. When combined with a claimed optical detection of the…

Astrophysics · Physics 2009-11-11 K. Mattila

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
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