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Title: γ-Ray And Parsec-Scale Jet Properties Of A Complete Sample Of Blazars From The Mojave Program

We investigate the Fermi LAT -ray and 15 GHz VLBA radio properties of a joint -ray- and radio-selected sample of AGNs obtained during the first 11 months of the Fermi mission (2008 Aug 4 - 2009 Jul 5). Our sample contains the brightest 173 AGNs in these bands above declination -30° during this period, and thus probes the full range of -ray loudness ( -ray to radio band luminosity ratio) in the bright blazar population. The latter quantity spans at least four orders ofmagnitude, reflecting a wide range of spectral energy distribution (SED) parameters in the bright blazar population. The BL Lac objects, however, display a linear correlation of increasing -ray loudness with synchrotron SED peak frequency, suggesting a universal SED shape for objects of this class. The synchrotron self-Compton model is favored for the -ray emission in these BL Lacs over external seed photon models, since the latter predict a dependence of Compton dominance on Doppler factor that would destroy any observed synchrotron SED peak - -ray loudness correlation. The high-synchrotron peaked (HSP) BL Lac objects are distinguished by lower than average radio core brightness temperatures, and none display large radio modulation indices or high linear core polarization levels.more » No equivalent trends are seen for the flat-spectrum radio quasars (FSRQ) in our sample. Given the association of such properties with relativistic beaming, we suggest that the HSP BL Lacs have generally lower Doppler factors than the lower-synchrotron peaked BL Lacs or FSRQs in our sample.« less
  1. Purdue Univ., West Lafayette, IN (United States); et al.
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 742; Journal Issue: 1; Journal ID: ISSN 0004-637X
Institute of Physics (IOP)
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
Contributing Orgs:
The MOJAVE Collaboration; The FERMI LAT Collaboration
Country of Publication:
United States
OSTI Identifier: