"X-shaped" radio sources. II. Sample properties Virtual Observatory Resource

Authors
  1. Saripalli L.
  2. Roberts D.H.
  3. Published by
    CDS
Abstract

In an earlier paper, we presented Jansky Very Large Array multi-frequency, multi-array continuum imaging of a unique sample of low-axial ratio radio galaxies. In this paper, the second in the series, we examine the images to learn the phenomenology of how the off-axis emission relates to the main radio source. Inversion-symmetric offset emission appears to be bimodal and to originate from one of two strategic locations: outer ends of radio lobes (outer-deviation) or from inner ends (inner-deviation). The latter sources are almost always associated with edge-brightened sources. With S- and Z-shaped sources being a subset of outer-deviation sources, this class lends itself naturally to explanations involving black hole axis precession. Our data allow us to present a plausible model for the more enigmatic inner-deviation sources with impressive wings; as for outer-deviation sources these too require black hole axis shifts, although they also require plasma backflows into relic channels. Evolution in morphology over time relates the variety in structures in inner-deviation sources including XRGs. With features such as non- collinearities, central inner-S "spine," corresponding lobe emission peaks, double and protruding hotspots not uncommon, black hole axis precession, drifts, or flips could be active in a significant fraction of radio sources with prominent off-axis emission. At least 4% of radio galaxies appear to undergo black hole axis rotation. Quasars offer a key signature for recognizing rotating axes. With a rich haul of sources that have likely undergone axis rotation, our work shows the usefulness of low-axial ratio sources in pursuing searches for binary supermassive black holes.

Keywords
  1. radio-galaxies
  2. radio-continuum-emission
  3. visible-astronomy
  4. sloan-photometry
  5. galaxy-classification-systems
Bibliographic source Bibcode
2018ApJ...852...48S
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/852/48
IVOA Identifier IVOID
ivo://CDS.VizieR/J/ApJ/852/48
Document Object Identifer DOI
doi:10.26093/cds/vizier.18520048

Access

Web browser access HTML
https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/852/48
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/852/48
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/852/48
IVOA Table Access TAP
https://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/852/48/sample?
https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/852/48/sample?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/852/48/sample?

History

2018-09-19T15:48:38Z
Resource record created
2018-09-19T15:48:38Z
Created
2018-10-23T07:57:03Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr