Radio and Gamma-ray Properties of Extragalactic Jets from the TANAMI Sample

M. Böck; M. Kadler; C. Müller; G. Tosti; R. Ojha; J. Wilms; D. Bastieri; T. Burnett; B. Carpenter; E. Cavazzuti; M. Dutka; J. Blanchard; P. G. Edwards; H. Hase; S. Horiuchi; D. L. Jauncey; F. Krauss; M. L. Lister; J. E. J. Lovell; B. Lott; D. W. Murphy; C. Phillips; C. Plötz; T. Pursimo; J. Quick; E. Ros; G. Taylor; D. J. Thompson; S. J. Tingay; A. Tzioumis; J. A. Zensus

doi:10.1051/0004-6361/201424773

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arXiv · 1601.05099

Radio and Gamma-ray Properties of Extragalactic Jets from the TANAMI Sample

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Abstract

Using high-resolution radio imaging with VLBI techniques, the TANAMI program has been observing the parsec-scale radio jets of southern (declination south of -30{\deg}) gamma-ray bright AGN simultaneously with Fermi/LAT monitoring of their gamma-ray emission. We present the radio and gamma-ray properties of the TANAMI sources based on one year of contemporaneous TANAMI and Fermi/LAT data. A large fraction (72%) of the TANAMI sample can be associated with bright gamma-ray sources for this time range. Association rates differ for different optical classes with all BL Lacs, 76% of quasars and just 17% of galaxies detected by the LAT. Upper limits were established on the gamma-ray flux from TANAMI sources not detected by LAT. This analysis led to the identification of three new Fermi sources whose detection was later confirmed. The gamma-ray and radio luminosities are related by $L_\gamma \propto L_r^{0.89+-0.04}$. The brightness temperatures of the radio cores increase with the average gamma-ray luminosity, and the presence of brightness temperatures above the inverse Compton limit implies strong Doppler boosting in those sources. The undetected sources have lower gamma/radio luminosity ratios and lower contemporaneous brightness temperatures. Unless the Fermi/LAT-undetected blazars are strongly gamma-ray-fainter than the Fermi/LAT-detected ones, their gamma-ray luminosity should not be significantly lower than the upper limits calculated here.

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M. Böck, M. Kadler, C. Müller, G. Tosti, R. Ojha, J. Wilms, D. Bastieri, T. Burnett, B. Carpenter, E. Cavazzuti, M. Dutka, J. Blanchard, P. G. Edwards, H. Hase, S. Horiuchi, D. L. Jauncey, F. Krauss, M. L. Lister, J. E. J. Lovell, B. Lott, D. W. Murphy, C. Phillips, C. Plötz, T. Pursimo, J. Quick, E. Ros, G. Taylor, D. J. Thompson, S. J. Tingay, A. Tzioumis, J. A. Zensus. 2016-01-19. Radio and Gamma-ray Properties of Extragalactic Jets from the TANAMI Sample. https://doi.org/10.1051/0004-6361/201424773

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