We are currently analyzing multi-frequency (2+4+6 cm) VLBA polarization observations of all sources from the complete sample of 1-Jy BL Lac objects defined by H. Kuhr and G. Schmidt. Total intensity and linear polarization images for several of the most interesting sources are presented, together with rotation-measure and spectral-index maps. In most of the sources, the measured milliarcsecond-scale rotation measures are consistent with integrated values, but in a number of cases, there is clear evidence for non-uniformity in the distribution of thermal plasma on parsec scales. We discuss overall characteristics of the polarization properties of the sample and their frequency dependence.
Galaxies and their Constituents at the Highest Angular Resolutions
- Pub Date:
- January 2001