Book contents
- Frontmatter
- Contents
- Index of Participants
- Preface
- I Evidence and Implications of Anisotropy in AGN
- II Luminosity Functions and Continuum Energy Distributions
- III The Broad Line Region: Variability and Structure
- IV X-rays and Accretion Disks
- V Beams, Jets and Blazars
- Magnetic Propulsion of Jets in AGN
- MHD Accretion-Ejection Model: X- and γ-rays and Formation of Relativistic Pair Beams
- Relativistic Electron Beams in AGN: Construction of Transonic Solutions
- Properties of Relativistic Jets
- A Massive Binary Black Hole in 1928+738?
- Gamma-Rays from Blazars: a Comparison of 3C 279, PKS 0537-441 and Mrk 421
- Microquasars in the Galactic Centre Region
- A Comparison of the Ultra-violet Continuum Variability Properties of Blazars and Seyfert 1s
- Simultaneous Optical and IR Monitoring of the Seyfert Nucleus NGC 7469
- Broad-Band Spectra and Polarization Properties of Variable Flat-Spectrum Radio Sources
- The Radio to Optical Variability of the BL Lac Object ON 231
- January 1992 Microvariability Campaign of OJ 287
- Blazar Microvariability: a Case Study of AO 0235+164
- Timescales of the Optical Variability of the BL Lacertae Galaxy PKS 2201+044
- Dynamics of Quasar Variability
- The Variability of a Large Sample of Quasars
- The Fate of Central Black Holes in Merging Galaxies
- Polarimetric Searching for Goldstone Bosons from AGNs
- VI Concluding Talk
MHD Accretion-Ejection Model: X- and γ-rays and Formation of Relativistic Pair Beams
from V - Beams, Jets and Blazars
Published online by Cambridge University Press: 04 August 2010
- Frontmatter
- Contents
- Index of Participants
- Preface
- I Evidence and Implications of Anisotropy in AGN
- II Luminosity Functions and Continuum Energy Distributions
- III The Broad Line Region: Variability and Structure
- IV X-rays and Accretion Disks
- V Beams, Jets and Blazars
- Magnetic Propulsion of Jets in AGN
- MHD Accretion-Ejection Model: X- and γ-rays and Formation of Relativistic Pair Beams
- Relativistic Electron Beams in AGN: Construction of Transonic Solutions
- Properties of Relativistic Jets
- A Massive Binary Black Hole in 1928+738?
- Gamma-Rays from Blazars: a Comparison of 3C 279, PKS 0537-441 and Mrk 421
- Microquasars in the Galactic Centre Region
- A Comparison of the Ultra-violet Continuum Variability Properties of Blazars and Seyfert 1s
- Simultaneous Optical and IR Monitoring of the Seyfert Nucleus NGC 7469
- Broad-Band Spectra and Polarization Properties of Variable Flat-Spectrum Radio Sources
- The Radio to Optical Variability of the BL Lac Object ON 231
- January 1992 Microvariability Campaign of OJ 287
- Blazar Microvariability: a Case Study of AO 0235+164
- Timescales of the Optical Variability of the BL Lacertae Galaxy PKS 2201+044
- Dynamics of Quasar Variability
- The Variability of a Large Sample of Quasars
- The Fate of Central Black Holes in Merging Galaxies
- Polarimetric Searching for Goldstone Bosons from AGNs
- VI Concluding Talk
Summary
Abstract
Gamma ray emission from extragalactic sources is interpreted as the Doppler boosted annihilation and Inverse Compton radiation from a relativistic electron-positron beam in the frame of the two-flow model. In the case of 3C279, the high luminosity and the rapid variability of gamma ray emission suggest a relativistically moving source, but even so the compactness cannot be smaller than unity at light week scale with a reasonable Doppler factor. This supports the two-flow model of extragalactic radio sources, where the small scale emission comes from a relativistic electron-positron beam, heated by a MHD jet responsible for the large-scale (kpc) radio structures.
Introduction
The GRO satellite has detected intense gamma ray emission from several Active Galactic Nuclei and quasars. Remarkably, all of them are associated with a flat spectrum radio source, whose radio spectral index αr is smaller than 0.5, and half of them exhibit known or probable superluminal motions (the others have not been observed at different epochs in VLBI). Just like the commonly invoked Doppler beaming amplification of radio emission, the high γ-ray luminosity suggests also that the emitting source is moving relativistically.
For 3C279 in particular, the spectrum reported by Hermsen & al. show a maximum emission per logarithmic energy interval around 10 MeV, with a photon spectral index of approximately 1.5 below the turn-over frequency and approximately 2 above it. A rapid flare has been observed with an increase of the luminosity by a factor 5 on a time scale of 2 days.
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- The Nature of Compact Objects in Active Galactic NucleiProceedings of the 33rd Herstmonceux Conference, held in Cambridge, July 6-22, 1992, pp. 368 - 371Publisher: Cambridge University PressPrint publication year: 1994