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D. H. Hough (Trinity University)
We are engaged in a long-term VLBI survey of a complete sample of 25 lobe-dominated quasars selected from the revised 3CR survey. Tha main motivation for this study is to conduct statistical tests of relativistic jet models and AGN unification scenarios, using a complete sample of sources with minimal orientation bias. To date, observations have been made of the nuclei in 24 objects. Each of the 19 objects that has been imaged shows a one-sided parsec-scale jet on the same side of the core as a one-sided kpc-scale jet. No counterjets have been detected. There is some tendency for sources with strong nuclei and small projected linear sizes to exhibit more prominent jets with greater curvature and more pronounced knots. Multiple-epoch images have been made for 11 objects; for 6 of these, it seems clear that the jet speeds are in the range of approximately 1-4c. Recent results include the first evidence for acceleration and nonradial motion of jet components, flat-spectrum cores and steep-spectrum jets, and a transition of the jet magnetic field from perpendicular to parallel to the jet axis. These results are all consistent with beaming and unification of core- and lobe-dominated quasars. (This work is currently supported by NSF grant AST-9422075).