A new bright z=6.82 quasar discovered with VISTA: VHS J0411-0907. (arXiv:1812.02481v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Pons_E/0/1/0/all/0/1">Estelle Pons</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+McMahon_R/0/1/0/all/0/1">Richard G. McMahon</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Simcoe_R/0/1/0/all/0/1">Robert A. Simcoe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Banerji_M/0/1/0/all/0/1">Manda Banerji</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hewett_P/0/1/0/all/0/1">Paul C. Hewett</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Reed_S/0/1/0/all/0/1">Sophie L. Reed</a>

We present the discovery of a new $z sim 6.8$ quasar discovered with the
near-IR VISTA Hemisphere Survey (VHS) which has been spectroscopically
confirmed by the ESO New Technology Telescope (NTT) and the Magellan telescope.
This quasar has been selected by spectral energy distribution (SED)
classification using near infrared data from VISTA, optical data from
Pan-STARRS, and mid-IR data from WISE. The SED classification algorithm is used
to statistically rank two classes; foreground Galactic low-mass stars and high
redshift quasars, prior to spectroscopic observation. Forced photometry on
Pan-STARRS pixels for VHS J0411-0907 allows to improve the SED classification
reduced-$chi^2$ and photometric redshift. VHS J0411-0907 ($z=6.82$, $y_{AB} =
20.1$ mag, $J_{AB} = 20.0$ mag) has the brightest J-band continuum magnitude of
the nine known quasars at $z > 6.7$ and is currently the highest redshift
quasar detected in the Pan-STARRS survey. This quasar has one of the lowest
black hole mass ($M_{rm{BH}}= (6.13 pm 0.51)times 10^8:mathrm{M_{odot}}$)
and the highest Eddington ratio ($2.37pm0.22$) of the known quasars at
$z>6.5$. The high Eddington ratio indicates that some very high-$z$ quasars are
undergoing super Eddington accretion. We also present coefficients of the best
polynomials fits for colours vs spectral type on the Pan-STARRS, VISTA and WISE
system for MLT dwarfs and present a forecast for the expected numbers of
quasars at $z>6.5$.

We present the discovery of a new $z sim 6.8$ quasar discovered with the
near-IR VISTA Hemisphere Survey (VHS) which has been spectroscopically
confirmed by the ESO New Technology Telescope (NTT) and the Magellan telescope.
This quasar has been selected by spectral energy distribution (SED)
classification using near infrared data from VISTA, optical data from
Pan-STARRS, and mid-IR data from WISE. The SED classification algorithm is used
to statistically rank two classes; foreground Galactic low-mass stars and high
redshift quasars, prior to spectroscopic observation. Forced photometry on
Pan-STARRS pixels for VHS J0411-0907 allows to improve the SED classification
reduced-$chi^2$ and photometric redshift. VHS J0411-0907 ($z=6.82$, $y_{AB} =
20.1$ mag, $J_{AB} = 20.0$ mag) has the brightest J-band continuum magnitude of
the nine known quasars at $z > 6.7$ and is currently the highest redshift
quasar detected in the Pan-STARRS survey. This quasar has one of the lowest
black hole mass ($M_{rm{BH}}= (6.13 pm 0.51)times 10^8:mathrm{M_{odot}}$)
and the highest Eddington ratio ($2.37pm0.22$) of the known quasars at
$z>6.5$. The high Eddington ratio indicates that some very high-$z$ quasars are
undergoing super Eddington accretion. We also present coefficients of the best
polynomials fits for colours vs spectral type on the Pan-STARRS, VISTA and WISE
system for MLT dwarfs and present a forecast for the expected numbers of
quasars at $z>6.5$.

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