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Title: Radio and gamma-ray properties of extragalactic jets from the TANAMI sample

The TANAMI program has been observing parsec-scale radio jets of southern (declination south of - 30°) γ-ray bright AGN, simultaneously with Fermi/LAT monitoring of their γ-ray emission, via high-resolution radio imaging with Very Long Baseline Interferometry techniques. In this paper, we present the radio and γ-rayproperties 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 γ-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 γ-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 γ-ray and radio luminosities are related by L γ ∝ L r 0.89±0.04. The brightness temperatures of the radio cores increase with the average γ-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 γ/radio luminosity ratios and lower contemporaneous brightness temperatures. Finally, unless the Fermi/LAT-undetected blazars are much γ-ray-fainter thanmore » the Fermi/LAT-detected sources, their γ-ray luminosity should not be significantly lower than the upper limits calculated here.« less
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Publication Date:
Grant/Contract Number:
AC02-76SF00515; NNH09ZDA001N; NNH10ZDA001N; 50OR0808; AYA2009-13036-C02-C02; AYA2012-38491-C02-01; Prometeo 2009/104; MP0905
Accepted Manuscript
Journal Name:
Astronomy and Astrophysics
Additional Journal Information:
Journal Volume: 590; Journal ID: ISSN 0004-6361
EDP Sciences
Research Org:
NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
Sponsoring Org:
USDOE; National Aeronautic and Space Administration (NASA); Federal Ministry for Economic Affairs and Energy (BMWi) (Germany); Ministry of Economy, Industry and Competitiveness (MINECO) (Spain); Generalitat Valenciana; European Cooperation in Science and Technology (COST) (Belgium)
Contributing Orgs:
Fermi LAT Collaboration
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; galaxies: active; galaxies: nuclei; galaxies: jets; gamma rays: galaxies; radio continuum: galaxies
OSTI Identifier: