Milli-arcsecond imaging of the radio emission from the quasar with the most massive black hole at reionization

Abstract

We report Very Long Baseline Array (VLBA) observations of the 1.5 GHz radio continuum emission of the {\it z=6.326} quasar SDSS J010013.02+280225.8 (hereafter J0100+2802). J0100+2802 is, by far the most optically luminous, and radio-quiet quasar with the most massive black hole known at z>6. The VLBA observations have a synthesized beam size of 12.10 mas $\times$5.36 mas (FWHM), and detected the radio continuum emission from this object with a peak surface brightness of 64.6+/-9.0 micro-Jy/beam and a total flux density of 88+/-19 micro-Jy. The position of the radio peak is consistent with that from SDSS in the optical and Chandra in the X-ray. The radio source is marginally resolved by the VLBA observations. A 2-D Gaussian fit to the image constrains the source size to $\rm (7.1+/-3.5) mas x (3.1+/-1.7) mas. This corresponds to a physical scale of (40+/-20) pc x (18+/-10) pc. We estimate the intrinsic brightness temperature of the VLBA source to be T_{B}=(1.6 +/- 1.2) x 10^{7} K. This is significantly higher than the maximum value in normal star forming galaxies, indicating an AGN origin for the radio continuum emission. However, it is also significantly lower than the brightness temperatures found in highest redshift radio-loud quasars. J0100+2802 provides a unique example to study the radio activity in optically luminous and radio quiet active galactic nuclei in the early universe. Further observations at multiple radio frequencies will accurately measure the spectral index and address the dominant radiation mechanism of the radio emission.

arXiv comment11 pages, 2 figures, accepted for publication in ApJLetter

References in corpus (29)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• A luminous quasar at a redshift of z = 7.085
• An ultra-luminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30
• The Canada-France High-z Quasar Survey: nine new quasars and the luminosity function at redshift 6
• DiFX2: A more flexible, efficient, robust and powerful software correlator
• A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey IV: Discovery of Seven Additional Quasars
• The Pan-STARRS1 distant z>5.6 quasar survey: more than 100 quasars within the first Gyr of the universe
• The Radio-Loud Fraction of Quasars is a Strong Function of Redshift and Optical Luminosity
• Evidence for non-evolving FeII/MgII ratios in rapidly accreting z~6 QSOs
• Black hole mass estimates and emission-line properties of a sample of redshift z>6.5 quasars
• Subaru high-z exploration of low-luminosity quasars (SHELLQs). I. Discovery of 15 quasars and bright galaxies at 5.7 < z < 6.9
• The Parsec-scale Radio Structure of NGC 1068 and the Nature of the Nuclear Radio Source
• Micro-Arcsecond Radio Astrometry
• The identification of z-dropouts in Pan-STARRS1: three quasars at 6.5<z<6.7
• Probing the Evolution of IR Properties of z~6 Quasars: Spitzer Observations
• Constraining the radio-loud fraction of quasars at z>5.5
• Probing the interstellar medium and star formation of the Most Luminous Quasar at z=6.3
• AGN Coronal Emission models I. The Predicted Radio Emission
• On the origin of radio core emission in radio-quiet quasars
• Discovery of Eight z ~ 6 Quasars in the Sloan Digital Sky Survey Overlap Regions
• Into the central 10 pc of the most distant known radio quasar. VLBI imaging observations of J1429+5447 at z=6.21
• NUclei of GAlaxies: V. Radio emission in 7 NUGA sources
• High-resolution double morphology of the most distant known radio quasar at z=6.12
• High-resolution radio imaging of the most distant radio quasar SDSS J0836+0054
• Radio structure of the most distant radio-detected quasar at the ten milli- arcsecond scale
• VLA and VLBA Observations of the Highest Redshift Radio-Loud QSO J1427+3312 at z = 6.12
• Continuum emission in NGC1068 and NGC3147: Indications for a turnover in the core spectra
• VLBI observations of the radio quasar J2228+0110 at z=5.95 and other field sources in multiple-phase-centre mode
• Exploratory Chandra observation of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.30

Cited by in corpus (10)

• Spatially Resolved Interstellar Medium and Highly-Excited Dense Molecular Gas in the Most Luminous Quasar at z=6.327
• Winds as the origin of radio emission in $z=2.5$ radio-quiet extremely red quasars
• Constraining the quasar radio-loud fraction at $z\sim 6$ with deep radio observations
• Radio-loud Quasars above Redshift 4: VLBI Imaging of an Extended Sample
• VLBI observations of VIK J2318-3113, a quasar at z = 6.44
• XMM-Newton observation of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.326
• Unveiling the weak radio quasar population at z $\ge$ 4
• Exploring the radio spectral energy distribution of the ultraluminous radio-quiet quasar SDSS J0100+2802 at redshift 6.3
• High-resolution Imaging of Two Radio Quasars at the End of the Reionization Epoch
• Milliarcsecond-scale radio structure of the most distant BL Lac object candidate at redshift 6.57