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Related papers: Insights into Extragalactic Background Light const…

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The attenuation produced by extragalactic background light (EBL) in $\gamma$-ray spectra of blazars has been used to constrain the Hubble constant ($H_0$) and matter density ($\Omega_{\rm m}$) of the Universe. We propose to estimate $H_0$…

High Energy Astrophysical Phenomena · Physics 2019-09-11 Houdun Zeng , Dahai Yan

The intrinsic flux of very high energy (VHE, Energy > 100 GeV) gamma-rays from extragalactic sources is attenuated due to pair production in the interaction with photons of the extragalactic background light (EBL). Depending on the distance…

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

Very high energy (VHE, E >100 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 2019-08-14 Daniel Mazin , Martin Raue , Bagmeet Behera , Susumu Inoue , Yoshiyuki Inoue , Takeshi Nakamori , Tomonori Totani

(Abridged) The extragalactic background light (EBL) observed at multiple wavelengths is a promising tool to probe the nature of dark matter since it might contain a significant contribution from gamma-rays produced promptly by dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-30 Jesus Zavala , Mark Vogelsberger , Tracy R. Slatyer , Abraham Loeb , Volker Springel

In this work, we use two different methods to determine the opacity of the TeV gamma-rays caused by the extragalactic background light (EBL) via e-e+ production due to photon-photon interaction. The first method, Model-Dependent Approach,…

High Energy Astrophysical Phenomena · Physics 2020-04-07 K. K. Singh , P. J. Meintjes

A brief white paper discussing the connections between the Extragalactic Background Light (EBL) and fundamental physics through gamma-ray observations is provided.

High Energy Astrophysical Phenomena · Physics 2013-05-01 Frank Krennrich , Matthew Orr

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

The study of the extragalactic background light (EBL) in the optical and near infrared has received a lot of attention in the last decade, especially near a wavelength of $\lambda\approx 3.4\operatorname{\mu m}$, with remaining tension…

We present models of the extragalactic background light (EBL) based on several scenarios of galaxy formation and evolution. We have treated galaxy formation with the Press-Schecter approximation for both cold dark matter (CDM) and cold+hot…

Astrophysics · Physics 2009-12-10 D. MacMinn , J. R. Primack

Gamma-rays propagating through space are likely to be extinguished via electron-positron pair production off of the ambient extragalactic background light (EBL). The spectrum of the EBL is produced by starlight (and starlight reprocessed by…

High Energy Astrophysical Phenomena · Physics 2013-12-11 Rebecca Reesman , T. P. Walker

We study the origin of the extragalactic diffuse gamma-ray background using the data from the Fermi telescope. To estimate the background level, we count photons at high Galactic latitudes |b|>60 degrees. Subtracting photons associated to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 A. Neronov , D. V. Semikoz

The Extragalactic Background Light (EBL) includes photons with wavelengths from ultraviolet to infrared, which are effective at attenuating gamma rays with energy above ~10 GeV during propagation from sources at cosmological distances. This…

High Energy Astrophysical Phenomena · Physics 2015-05-18 The Fermi LAT , the GBM Collaboration , : , A. A. Abdo

We report the observation in the GeV band of the blazar 1ES 0229+200, which over recent years has become one the primary sources used to put constraints on the Extragalactic Background Light (EBL) and Extragalactic Magnetic Field (EGMF). We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Ievgen Vovk , Andrew M. Taylor , Dmitri Semikoz , Andrii Neronov

The absorption of gamma-rays in the intergalactic medium due to the EBL (Extragalactic Background Light) causes the observed blazar spectrum to be fainter and softer than their intrinsic state. It could thus be expected to see an effective…

High Energy Astrophysical Phenomena · Physics 2009-01-22 B. Behera , S. J. Wagner

I review the constraints imposed by the observed extragalactic background light (EBL) on the history of the stellar birthrate in galaxies. At faint magnitudes, the logarithmic slope of the galaxy counts is flatter than 0.4 in all seven…

Astrophysics · Physics 2009-10-31 Piero Madau

We present predictions for the UV-to-mm extragalactic background light (EBL) from a recent version of the GALFORM semi-analytical model of galaxy formation which invokes a top-heavy stellar initial mass function (IMF) for galaxies…

Astrophysics of Galaxies · Physics 2019-06-19 William. I. Cowley , Cedric G. Lacey , Carlton M. Baugh , Shaun Cole , Carlos S. Frenk , Claudia del P. Lagos

Extragalactic Background Light (EBL) studies have revealed a significant discrepancy between direct measurements -- via instruments measuring "bare" sky from which Zodiacal and Galactic light models are subtracted -- and measurements of the…

In this chapter, we discuss the contributions of gamma-ray astronomy at TeV energies to our understanding of the visible content and structure of the universe. We start from the present epoch with the second most intense electromagnetic…

High Energy Astrophysical Phenomena · Physics 2021-12-14 Elisa Pueschel , Jonathan Biteau

We re-derive the possible dependence of the redshift with very high energy (VHE) $\gamma$-ray photon index. The results suggest that the universe to VHE $\gamma$-rays is becoming more transparent than usually expected. We introduce the…

High Energy Astrophysical Phenomena · Physics 2023-08-02 L. J. Dong , Y. G. Zheng , S. J. Kang

The extragalactic background light records the history of infrared, optical and ultraviolet light radiation including re-radiation since the epoch of reionization. While challenging to measure directly, it can be measured indirectly via its…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Elisa Pueschel
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