2003/01/16 by M. L. Lister, Lister, M. L.
Physics and Astronomy · #Astrophysics (astro-ph) #Astrophysics and Cosmic Phenomena #FOS: Physical sciences #Gamma-ray bursts and supernovae #Radio Astronomy Observations and Technology #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0301332
9 pages, to appear in "Radio Astronomy at the Fringe"; a conference held in Green Bank, WV in honor of Ken Kellermann's 65th birthday, eds. J.A. Zensus, M.H. Cohen, & E. Ros, ASP Conference Series (2003)
arxiv created 2003/01/16 · openalex publication_date 2003/01/16 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The study of compact active galactic nuclei (AGN) that possess convex radio spectra (the gigahertz-peaked spectrum radio sources) offers a unique opportunity to probe both the early evolutionary stages of relativistic AGN jets and their immediate nuclear environments. In this article I trace Ken Kellermann's early investigations of these sources, which played a major role in justifying the development of modern-day VLBI techniques. I describe how our understanding of these AGN has progressed since Kellermann's early discoveries, and discuss several ways in which the current classification scheme can be simplified to reflect intrinsic source characteristics, rather than observer-biased quantities. Finally, I discuss recent results from the VLBA 2 cm survey concerning the relativistic jet kinematics of the two-sided peaked-spectrum sources 4C +12.50 (PKS 1345+125) and OQ 208 (1404+286).