Characteristics of Gamma-Ray Loud Blazars in the VLBA Imaging and Polarimetry Survey

Abstract

The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey. This large, flux-limited sample of active galactic nuclei (AGNs) provides insights into the mechanism that produces strong gamma-ray emission. At lower flux levels, radio flux density does not directly correlate with gamma-ray flux. We find that the LAT-detected BL Lac objects tend to be similar to the non-LAT BL Lac objects, but that the LAT-detected FSRQs are often significantly different from the non-LAT FSRQs. The differences between the gamma-ray loud and quiet FSRQS can be explained by Doppler boosting; these objects appear to require larger Doppler factors than those of the BL Lac objects. It is possible that the gamma-ray loud FSRQs are fundamentally different from the gamma-ray quiet FSRQs. Strong polarization at the base of the jet appears to be a signature for gamma-ray loud AGNs.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2010
Accession Number
ADA554848

Entities

People

  • A. C. Readhead
  • G. Cotter
  • G. Taylor
  • J. D. Linford
  • J. F. Helmboldt
  • J. L. Richards
  • R. Reeves
  • R. W. Romani
  • S. E. Healey

Organizations

  • University of New Mexico

Tags

Communities of Interest

  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • Astronomy
  • Detection
  • Emission
  • Flux Density
  • Gamma Rays
  • Grids
  • Jet Propulsion
  • Line Of Sight
  • Materials
  • Measurement
  • Observation
  • Polarimetry
  • Polarization
  • Radiation
  • Spectra
  • Statistical Sampling
  • Universities

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics

Technology Areas

  • Space