Exploring the Radio Spectral Energy Distribution of the Ultraluminous Radio-quiet Quasar SDSS J0100+2802 at Redshift 6.3
Authors
Wagg, J
Fei, Q
Xu, F
Publication Date
2022Journal Title
Astrophysical Journal
ISSN
0004-637X
Publisher
American Astronomical Society
Volume
929
Issue
1
Language
en
Type
Article
This Version
VoR
Metadata
Show full item recordCitation
Liu, Y., Wang, R., Momjian, E., Wagg, J., Yang, X., An, T., Shao, Y., et al. (2022). Exploring the Radio Spectral Energy Distribution of the Ultraluminous Radio-quiet Quasar SDSS J0100+2802 at Redshift 6.3. Astrophysical Journal, 929 (1) https://doi.org/10.3847/1538-4357/ac5c50
Abstract
<jats:title>Abstract</jats:title>
<jats:p>We report deep Karl G. Jansky Very Large Array (VLA) observations of the optically ultraluminous and radio-quiet quasar SDSS J010013.02+280225.8 (hereafter J0100+2802) at redshift <jats:italic>z</jats:italic> = 6.3. We detected the radio continuum emission at 1.5 GHz, 6 GHz, and 10 GHz. This leads to a radio power-law spectral index of <jats:italic>α</jats:italic> = −0.52 ± 0.18 (<jats:italic>S</jats:italic> ∝ <jats:italic>ν</jats:italic>
<jats:sup>
<jats:italic>α</jats:italic>
</jats:sup>). The radio source is unresolved in all VLA bands with an upper limit to the size of 0.″2 (i.e., ∼1.1 kpc) at 10 GHz. We find variability in the flux density (increase by ∼33%) and the spectral index (steepened) between observations in 2016 and 2017. We also find that the VLA 1.5 GHz flux density observed in the same year is 1.5 times that detected with the Very Long Baseline Array (VLBA) in 2016 at the same frequency. This difference suggests that half of the radio emission from J0100+2802 comes from a compact core within 40 pc, and the rest comes from the surrounding few-kiloparsec area, which is diffuse and resolved out in the VLBA observations. The diffuse emission is 4 times brighter than what would be expected if driven by star formation. We conclude that the central active galactic nucleus is the dominant power engine of the radio emission in J0100+2802.</jats:p>
Keywords
310, Galaxies and Cosmology
Sponsorship
National Key Program for Science and Technology Research and Development (2016YFA0400703)
National Science Foundation of China (NSFC) (11721303, 11991052, 11373008, 11533001)
Identifiers
apjac5c50, ac5c50, aas35250
External DOI: https://doi.org/10.3847/1538-4357/ac5c50
This record's URL: https://www.repository.cam.ac.uk/handle/1810/336061
Rights
Licence:
http://creativecommons.org/licenses/by/4.0/
Statistics
Total file downloads (since January 2020). For more information on metrics see the
IRUS guide.