2001/01/04 by Gordon T. Richards, S. A. Laurent-Muehleisen, S. A. Laurent‐Muehleisen +2 · 1 citation
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #Radio Astronomy Observations and Technology #astro-ph
paper · pdf · doi:10.1086/318414
published as February 2001, ApJ, 547, 635 · 34 pages, 7 figures, 3 tables, ApJ in press
arxiv created 2001/01/04 · openalex publication_date 2001/02/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present high-resolution radio data at 3.5 and 20 cm from the VLA in the A configuration for 144 quasars with known C IV absorption-line properties. Using these measurements, we compare and contrast a number of quasar orientation indicators. These quantities are used to study the velocity distribution of C IV absorption lines as a function of quasar orientation measures. That there is an excess of narrow, high-velocity C IV absorbers in flat spectrum quasars as compared to steep spectrum quasars is confirmed. Orientation indicators that are not based upon spectral indices (e.g., R V and the core-to-lobe ratio) do not show the same effect. These seemingly contradictory results may be reconciled if the absorber distribution is not strictly a function of orientation, but rather a function of intrinsic radio properties that may or may not be good orientation indicators.