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arXiv · 2105.05396

Parsec-scale Properties of eight Fanaroff-Riley Type 0 Radio Galaxies

Xiaopeng Cheng·Tao An·Bong Won Sohn·Xiaoyu Hong·Ailing Wang
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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 mas. 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, but 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 that the pc-scale FR 0 jets are mildly relativistic with lower bulk Lorentz factors and larger viewing angles.

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Xiaopeng Cheng, Tao An, Bong Won Sohn, Xiaoyu Hong, Ailing Wang. 2021-05-12. Parsec-scale Properties of eight Fanaroff-Riley Type 0 Radio Galaxies. https://doi.org/10.1093/mnras/stab1388

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