English
Related papers

Related papers: Extragalactic Background Light Inferred from AEGIS…

200 papers

We introduce a new method to determine the redshift of unknown-redshift BL Lac Objects. The method relies on simultaneous multi-wavelength (MWL) observations of BL Lac objects in optical, X-ray, HE (E>100 MeV) gamma-rays and VHE (E>100…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Nijil Mankuzhiyil , Stefano Ansoldi , Gessica De Caneva , Massimo Persic , Fabrizio Tavecchio

Very high energy (VHE, E > 30 GeV) gamma-rays are absorbed via interaction with low-energy photons from the extragalactic background light (EBL) if the involved photon energies are above the threshold for electron-positron pair creation.…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 D. Mazin

We present a current best estimate of the integrated near-infrared (NIR) extragalactic background light (EBL) attributable to resolved galaxies in J, H, and Ks. Our results in units of nW m-2 sr-1 are 11.7+5.6 -2.6 in J, 11.5+4.5 -1.5 in H…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-18 Ryan C. Keenan , Amy J. Barger , Lennox L. Cowie , Wei-Hao Wang

We present a current best estimate of the integrated near-infrared (NIR) extragalactic background light (EBL) attributable to resolved galaxies in J, H, and Ks . Our results for measurements of {\nu}I{\nu} in units of nW m-2 sr-1 are…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-18 R. C. Keenan , A. J. Barger , L. L. Cowie , W. -H. Wang

The diffuse extragalactic background light consists of the sum of the starlight emitted by galaxies through the history of the Universe, and it could also have an important contribution from the first stars, which may have formed before…

Astrophysics · Physics 2012-08-27 H. E. S. S. Collaboration , : , F. Aharonian

The Extragalactic Background Light (EBL) is the integrated light from all the stars that have ever formed, and spans the IR-UV range. The interaction of very-high-energy (VHE: E>100 GeV) gamma-rays, emitted by sources located at…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Nijil Mankuzhiyil , Massimo Persic , Fabrizio Tavecchio

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

We update the list of GeV-TeV extragalactic \gamma-ray sources using the 2-year catalog from the Fermi-LAT and recent results ground-based \gamma-ray telescopes. Breaks in the spectra between the high energy (100 MeV <E< 300 GeV) and the…

High Energy Astrophysical Phenomena · Physics 2013-06-05 D. A. Sanchez , S. Fegan , B. Giebels

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

High-energy photons from cosmological emitters suffer attenuation due to pair production interactions with the extragalactic background light (EBL). The collective emission of any high-energy emitting cosmological population will exhibit an…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Tonia M. Venters , Vasiliki Pavlidou , Luis C. Reyes

The extragalactic background light (EBL) is comprised of the cumulative radiation from all galaxies and active galactic nuclei over the cosmic history. In addition to point sources, EBL also contains information from diffuse sources of…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-23 Yan Gong , Asantha Cooray , Ketron Mitchell-Wynne , Xuelei Chen , Michael Zemcov , Joseph Smidt

The vast majority of extragalactic sources detected in the very high energy (E> 100 GeV) domaine are active galactic nuclei (AGN) located at cosmological distances. During their travel towards Earth, the emitted gamma-rays suffer from…

High Energy Astrophysical Phenomena · Physics 2019-08-15 C. Romoli , D. A. Sanchez , M. Lorentz , P. Brun

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

This article outlines a method to interpret the extragalactic background light in terms of the large-scale, average properties of galaxies, including the comoving densities of stars and interstellar gas, metals, and dust. These quantities…

Astrophysics · Physics 2007-05-23 S. Michael Fall

We present a two-parameter model of the extragalactic gamma-ray background (EGB) in the 0.1-100 GeV range as measured by the Large Area Telescope (LAT) onboard the Fermi satellite. The EGB can be fully explained as the sum of three distinct…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-25 Massimo Cavadini , Ruben Salvaterra , Francesco Haardt

Very high energy (VHE) $\gamma$-rays above 10$'$s of GeV energy, emitted from distant blazars, are attenuated by photons from the extragalactic background light (EBL). Unfortunately, neither the EBL nor the intrinsic blazar spectrum is…

High Energy Astrophysical Phenomena · Physics 2015-06-17 K K Singh , S Sahayanathan , A K Tickoo , N Bhatt

We present a measurement of the absolute surface brightness of the zodiacal light (3900-5100A) toward a fixed extragalactic target at high ecliptic latitude based on moderate resolution (~1.3A per pixel) spectrophotometry obtained with the…

Astrophysics · Physics 2009-11-07 R. A. Bernstein , W. L. Freedman , B. F. Madore

The unexpectedly hard very-high-energy (VHE; $E > 100$ GeV) $\gamma$-ray spectra of a few distant blazars have been interpreted as evidence for a reduction of the $\gamma\gamma$ opacity of the Universe due to the interaction of VHE…

High Energy Astrophysical Phenomena · Physics 2017-02-08 Hassan Abdalla , Markus Boettcher

Aims: Our aim is to study the production mechanism for very-high-energy (VHE; >100GeV) gamma-rays in distant active galactic nuclei (AGN) and use the observed VHE spectrum to derive limits on the Extragalactic Background Light (EBL). We…

Astrophysics · Physics 2009-04-16 HESS Collaboration , F. Aharonian

The latest determination of the extragalactic gamma-ray background (EGRB) radiation by Fermi is compared with the theoretical prediction of the blazar component by Inoue & Totani (2009; hereafter IT09). The Fermi EGRB spectrum is in…

High Energy Astrophysical Phenomena · Physics 2010-01-05 Yoshiyuki Inoue , Tomonori Totani , Susumu Inoue , Masakazu A. R. Kobayashi , Jun Kataoka , Rie Sato