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First meeting of the year: Accretion disk winds and quasar feedback; 10 billion solar masses black hole at z=6.3

We discussed two Nature papers. One was published last week and the other a couple of weeks ago.

An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30, Nature

João presented the Nature paper An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30, Nature

Weak points: identification of quasar by colors (came from SDSS); application of local reverberation mapping scaling to such object at high-z is risky.

This paper has been featured quite a lot in the news lately. See also the feature:Feature: A giant in the young universe.

Wind from black hole accretion disk as the driver of a molecular outflow in a galaxy, Nature

Rodrigo presented the Nature paper by Tombesi et al. This paper was expected to be published at anytime and made it into the cover of the magazine on March 25th.

26.3_cover_proof_one

First time, as far as I know, that the origin of large-scale molecular outflows which are associated with quasar feedback in ULIRGs — operating in scales of hundreds of pc — is connected with an origin in the accretion disk winds coming from scales of 1E-4 pc (~100 Schwarzschild radii). Energetics is consistent between the two outflows and the inner wind has speeds of ~0.2c. Inner wind observed via absorption in Suzaku X-ray spectrum while large-scale outflows comes from absorption seen with Herschel.

UFOs are not a consensus among X-ray “spectroscopists” and some believe they are a statistical fluke.

A vigorous discussion followed involving Bete and Claudio. They argued that the interpretation put forward by Tombesi et al. of the observations is not favored. From what I could understand from their arguments, they favor a starburst origin for the wind or a jet origin both of which do not seem to be favored by the observations of the mildly relativistic inner wind and the fact that ULIRGs are generally radio-quiet.

Other papers we noticed

Powerful Outflows and Feedback from Active Galactic Nuclei, ARA&A

http://adsabs.harvard.edu/abs/2015arXiv150305206K
Polarization Swings Reveal Magnetic Energy Dissipation in Blazars

http://adsabs.harvard.edu/abs/2015arXiv150207825Z
Black hole feedback in the luminous quasar PDS 456, Science (the “brazilian” quasar)

http://m.sciencemag.org/content/347/6224/860.full
(this one will be discussed in a future meeting)

One of the articles in the special edition of Science: GR Turns 100

http://www.sciencemag.org/content/347/6226.toc
A Planck-scale limit on spacetime fuzziness and stochastic Lorentz invariance violation, Nature Physics

http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys3270.html

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