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arXiv · 1010.5812

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

J. D. Linford·G. B. Taylor·R. Romani·S. E. Healey·J. F. Helmboldt·A. C. S. Readhead·R. Reeves·J. Richards·G. Cotter
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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 (VIPS). This large, flux-limited sample of active galactic nuclei (AGN) 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 Lacs tend to be similar to the non-LAT BL Lacs, 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 Lacs. 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 AGN.

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J. D. Linford, G. B. Taylor, R. Romani, S. E. Healey, J. F. Helmboldt, A. C. S. Readhead, R. Reeves, J. Richards, G. Cotter. 2010-10-27. Characteristics of Gamma-Ray Loud Blazars in the VLBA Imaging and Polarimetry Survey. https://doi.org/10.1088/0004-637x%2F726%2F1%2F16

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