1999/03/21 by B. I. Grimberg, E. M. Sadler, S. M. Simkin
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1086/307547
12 pages, 3 fig pages, to appear in the Astrophys. J
arxiv created 1999/03/21 · openalex publication_date 1999/08/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
PKS 0349-27 is a classical FR II radio galaxy whose active galactic nucleus host has a spectacular, spiral-like structure in its extended emission line gas (EELG). We have measured the velocity field in this gas and find that it splits into two cloud groups separated by radial velocities that at some points approach 400 km s -1 . Measurements of the diagnostic emission line ratios [O III] 5007/Hβ, [S II] 6716+6731/Hα, and [N II] 6583/Hα in these clouds show no evidence for the type of H II region emission associated with starburst activity in either velocity system. The measured emission line ratios are similar to those found in the nuclei of narrow-line radio galaxies, but the extended ionization/excitation cannot be produced by continuum emission from the active nucleus alone. We present arguments that suggest that the velocity disturbances seen in the EELG are most likely the result of a galaxy-galaxy collision or merger, but we cannot completely rule out the possibility that the gas has been disrupted by the passage of a radio jet.