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Analysis of 6cm VLBI polarization observations of a complete sample of northern BL Lacertae Objects

D. C. Gabuzda·A. B. Pushkarev·T. V. Cawthorne
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Abstract

The results of VLBI total intensity (I) and linear polarization (P) observations at 6cm are presented for ten radio bright BL Lacertae objects. These images complete first-epoch polarization observations for the 1-Jy sample of northern BL Lacertae objects defined by Kuhr and Schmidt. Estimates of superluminal speeds are presented for several sources, bringing the total number of sources in the sample for which such estimates are available to 16. Second epoch observations currently being reduced should yield speed estimates for VLBI features in essentially all the sources in the sample. The jet magnetic fields of these BL Lacertae objects are usually transverse to the local jet direction, but a sizeable minority (about 30%) have VLBI jet components with longitudinal magnetic fields. This may suggest that the conditions in the VLBI jets of BL Lacertae objects are favorable for the formation of relativistic shocks; alternatively, it may be that the toroidal component of the intrinsic jet magnetic field is characteristically dominant in these sources.

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D. C. Gabuzda, A. B. Pushkarev, T. V. Cawthorne. 2003-07-09. Analysis of 6cm VLBI polarization observations of a complete sample of northern BL Lacertae Objects. https://doi.org/10.1046/j.1365-8711.2000.03932.x

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