Published in Advances in Space Research, Vol. 21, Issue 1-2, p. 89, 1998


MULTIWAVELENGTH PROPERTIES OF BLAZARS

C. Megan Urry

Space Telescope Science Institute, 3700 San Martin Drive, Baltimore MD 21218, USA


ABSTRACT. The multiwavelength spectra of blazars appear to be dominated by nonthermal emission from a relativistic jet oriented close to the line of sight. The recent detection of many blazars at gamma-ray energies strongly supports this scenario. High quality multiwavelength monitoring data for the brightest one or two blazars suggest the optical through X-ray continuum is synchrotron emission from an inhomogeneous jet. The gamma-rays are likely due to Compton scattering of lower energy photons, either from within the jet or from the surrounding gas. The physical properties of the jet and the way in which it is produced are still largely a mystery but are probably related in some way to accretion onto a central supermassive black hole. There is little direct observational evidence for accretion disks in blazars, although there is evidence for winds which might emanate from disks.


Table of Contents

ball6 BLAZARS IN RELATION TO OTHER AGN

ball6 GAMMA-RAY EVIDENCE FOR BULK RELATIVISTIC MOTION

ball6 THE SIGNIFICANCE OF BLAZARS FOR UNDERSTANDING AGN AND BLACK HOLES

ball6 WHAT IS NOT KNOWN ABOUT BLAZARS

ball6 MULTIWAVELENGTH SPECTRA OF BLAZARS

ball6 MULTIWAVELENGTH VARIABILITY OF BLAZARS

ball6 PRODUCTION OF GAMMA RAYS: THE MULTIWAVELENGTH VARIABILITY OF 3C 279

ball6 JET STRUCTURE: THE MULTIWAVELENGTH VARIABILITY OF PKS 2155-304

ball6 WHAT WE NOW KNOW ABOUT BLAZARS

ball6 REFERENCES

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