Kiloparsec-scale jets in FR I radio galaxies and the γ-ray background

Stawarz, T. M. Kneiske, Jun Kataoka

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

We discuss the contribution of kiloparsec-scale jets in FR I radio galaxies to the difiuse γ-ray background radiation. The analyzed γ-ray emission comes from inverse-Compton scattering of starlight photon fields by the ultrarelativistic electrons whose synchrotron radiation is detected from such sources at radio, optical, and X-ray energies. We find that these objects, under the minimum-power hypothesis (corresponding to a magnetic field of 300 μG in the brightest knots of these jets), can contribute about one percent to the extragalactic γ-ray background measured by EGRET. We point out that this result already indicates that the magnetic fields in kiloparsec-scale jets of low-power radio galaxies are not likely to be smaller than 10 μG on average, as otherwise the extragalactic γ-ray background would be overproduced.

Original languageEnglish
Pages (from-to)693-698
Number of pages6
JournalAstrophysical Journal
Volume637
Issue number2 I
DOIs
Publication statusPublished - 2006 Feb 1
Externally publishedYes

Fingerprint

radio galaxies
rays
radio
magnetic field
background radiation
scattering
magnetic fields
electron
synchrotron radiation
energy
photons
electrons
x rays

Keywords

  • Galaxies: active
  • Galaxies: jets
  • Gamma rays: theory
  • Radiation mechanisms: nonthermal

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Kiloparsec-scale jets in FR I radio galaxies and the γ-ray background. / Stawarz; Kneiske, T. M.; Kataoka, Jun.

In: Astrophysical Journal, Vol. 637, No. 2 I, 01.02.2006, p. 693-698.

Research output: Contribution to journalArticle

Stawarz ; Kneiske, T. M. ; Kataoka, Jun. / Kiloparsec-scale jets in FR I radio galaxies and the γ-ray background. In: Astrophysical Journal. 2006 ; Vol. 637, No. 2 I. pp. 693-698.
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