1997/11/12 by E. J. M. Colbert, Edward J. M. Colbert, Stefi A. Baum +3 · 51 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #Galaxy #Physics #ROSAT #Radio galaxy #astro-ph
paper · pdf · doi:10.1086/305417
published in The Astrophysical Journal 496(2), 786-796 (IOP Publishing) · 24 pages, 7 ps figures, AASTEX 4.0, accepted for ApJ April 1, 1998
arxiv created 1997/11/12 · openalex publication_date 1998/04/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present ROSAT PSPC and HRI images of eight galaxies selected from a distance-limited sample of 22 edge-on Seyfert galaxies. Kiloparsec-scale soft X-ray nebulae extend along the galaxy minor axes in three galaxies (NGC 2992, NGC 4388, and NGC 5506). The extended X-ray emission has 0.2-2.4 keV X-ray luminosities of 0.4-3.5 × 10 40 ergs s -1 . The X-ray nebulae are roughly cospatial with the large-scale radio emission, suggesting that both are produced by large-scale galactic outflows. Assuming pressure balance between the radio and X-ray plasmas, the X-ray filling factor is ≳10 4 times larger than the radio plasma filling factor, suggesting that large-scale outflows in Seyfert galaxies are predominantly winds of thermal X-ray-emitting gas. We favor an interpretation in which large-scale outflows originate as active galactic nucleus-driven jets that entrain and heat gas on kiloparsec scales as they make their way out of the galaxy. Active galactic nucleus- and starburst-driven winds are also possible explanations in cases where the winds are oriented along the rotation axis of the galaxy disk.