Can the extragalactic gamma-ray background be explained by AGN?

Tanja M. Kneiske, Karl Mannheim, Lukasz Stawarz, Jun Kataoka

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Very high energy gamma-rays from blazars traversing cosmological distances through the meta-galactic radiation field can convert into electron-positron pairs in photon-photon collisions. The converted gamma-rays initiate electromagnetic cascades driven by inverse-Compton scattering with microwave background photons. Using a model for the time-dependent meta-galactic radiation field consistent with currently available far-infrared to optical data, the cascade contributions by faint, unresolved sources like blazars and FRI galaxies have been calculated. We come to the conclusion that depending on what is known so far about AGN, they are not able to produce the total extragalactic flux detected by EGRET. A test for the model will be the upcoming observations with FERMI. It would also be helpful to detect a signal above 100 GeV where the gamma-ray flux declines to 10 -7GeV sr -1 cm -2 s -1.

Original languageEnglish
Title of host publicationAIP Conference Proceedings
Pages510-513
Number of pages4
Volume1085
DOIs
Publication statusPublished - 2009
Externally publishedYes
Event4th International Meeting on High Energy Gamma-Ray Astronomy - Heidelberg, Germany
Duration: 2008 Jul 72008 Jul 11

Other

Other4th International Meeting on High Energy Gamma-Ray Astronomy
CountryGermany
CityHeidelberg
Period08/7/708/7/11

Fingerprint

galactic radiation
blazars
gamma rays
radiation distribution
cascades
photons
electron-positron pairs
electromagnetism
galaxies
microwaves
collisions
scattering
energy

Keywords

  • Background radiations
  • Gamma-ray sources

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Kneiske, T. M., Mannheim, K., Stawarz, L., & Kataoka, J. (2009). Can the extragalactic gamma-ray background be explained by AGN? In AIP Conference Proceedings (Vol. 1085, pp. 510-513) https://doi.org/10.1063/1.3076721

Can the extragalactic gamma-ray background be explained by AGN? / Kneiske, Tanja M.; Mannheim, Karl; Stawarz, Lukasz; Kataoka, Jun.

AIP Conference Proceedings. Vol. 1085 2009. p. 510-513.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Kneiske, TM, Mannheim, K, Stawarz, L & Kataoka, J 2009, Can the extragalactic gamma-ray background be explained by AGN? in AIP Conference Proceedings. vol. 1085, pp. 510-513, 4th International Meeting on High Energy Gamma-Ray Astronomy, Heidelberg, Germany, 08/7/7. https://doi.org/10.1063/1.3076721
Kneiske TM, Mannheim K, Stawarz L, Kataoka J. Can the extragalactic gamma-ray background be explained by AGN? In AIP Conference Proceedings. Vol. 1085. 2009. p. 510-513 https://doi.org/10.1063/1.3076721
Kneiske, Tanja M. ; Mannheim, Karl ; Stawarz, Lukasz ; Kataoka, Jun. / Can the extragalactic gamma-ray background be explained by AGN?. AIP Conference Proceedings. Vol. 1085 2009. pp. 510-513
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