Parsec-scale properties of eight Fanaroff–Riley type 0 radio galaxies. Issue 2 (15th July 2021)

• Record Type: Journal Article
• Authors: Cheng, Xiaopeng; An, Tao; Sohn, Bong Won; Hong, Xiaoyu; Wang, Ailing
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 506:Issue 2(2021)
• Page Start: 1609
• Page End: 1622
• Publication Date: 2021-07-15
• Subjects: galaxies: active -- galaxies: jets -- galaxies: kinematics and dynamics; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stab1388
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: We report the high-resolution radio observations of eight Fanaroff–Riley type 0 radio galaxies (FR 0s), selected from the published FR 0 sample. These observations were carried out with the Very Long Baseline Array (VLBA) and European VLBI Network (EVN) at frequencies of 5 and 8 GHz with a highest resolution of ∼0.6 milliarcsec. All eight sources show compact structures on projected physical sizes of 0.3–10 parsec. Six sources show a two-sided structure and two sources show a one-sided jet structure. J1025+1022 shows an X-shaped jet structure, which could result from a reorientation of the jet axis due to a restart of the central engine or a projection of a highly curved inner jet. However, more studies are needed to examine these scenarios. Proper motions for 22 jet components of the eight sources are determined to be between $-0.08\, c$ and $0.51\, c$ . Although most of the sources exhibit flat spectra, other observed characteristics, such as low-amplitude flux density variations, low jet proper motion speeds and symmetric two-sided jet structures, tend to support the fact that the parsec-scale FR 0 jets are mildly relativistic with lower bulk Lorentz factors and larger viewing angles.