2007/08/22 by Y. Y. Kovalev, M. L. Lister, D. C. Homan +1 · 11 citations
Physics and Astronomy · #Active galactic nucleus #Astrophysical jet #Astrophysics #Astrophysics and Cosmic Phenomena #Flow (mathematics) #Flux (metallurgy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Jet (fluid) #Mechanics #Physics #Radio Astronomy Observations and Technology #Radio galaxy #Relativistic beaming #astro-ph
paper · pdf · doi:10.1086/522603
published as Astroph.J.Lett. 668 (2007), 27-30 · 4 pages, 2 color figures, 1 table, accepted for publication in the Astrophysical Journal Letters; a typo in a reference has been corrected
arxiv created 2007/08/22 · openalex publication_date 2007/09/25 · arxiv updated 2009/12/01 · openalex created_date 2022/09/03 · openalex updated_date 2026/08/05
We report new 2 cm VLBA images of the inner radio jet of M87 showing a limb-brightened structure and unambiguous evidence for a faint 3 mas long counterfeature which also appears limb brightened. Multiepoch observations of seven separate jet features show typical speeds of less than a few percent of the speed of light, despite the highly asymmetric jet structure and the implications of the canonical relativistic beaming scenario. The observed morphology is consistent with a two-stream spine-sheath velocity gradient across the jet, as might be expected from the recently discovered strong and variable TeV emission as well as from numerical modeling of relativistic jets. Considering the large jet-to-counterjet flux density ratio and lack of observed fast motion in the jet, we conclude that either the inner part of the M87 jet is intrinsically asymmetric or that the bulk plasma flow speed is much greater than any propagation of shocks or other pattern motions.