KITP Notes – Massive Black Holes – Thurs PM

Gültekin – “Probing the black hole-­‐galaxy scaling relations: present and past”

  • Uncorrelated BH seeding -> M-sigma.  I first saw this in a conference in Potsdam (2010). Interesting, but they considered a 100% occupation fraction. Peng (2007), Jahnke & Maccio (2010).
  • Low scatter in M-sigma, but there are some outliers (e.g. NGC 1277)! Forming too many / little stars.  Are there selection effects?
  • Low-mass end is important to understand the BH seeds
  • High-mass end is also important! 1010 Msun implied in some hosts.

di Matteo – “Supermassive black holes in cosmic structure formation”

  • Tidal torquing to calculate \dot{MBH} (DeBuhr, Hopkins, Ma 2011). Angles-­Alcazar (see talk from earlier today) also uses something similar.
  • No dependence on resolution when compared to MassiveBlack down to 100 pc resolution. Really? Missing physics? Implementation? Mayer: “… maybe you’re converging to the wrong solution …” in the Q&A session.

Treu – “Co-evolution of Galaxies and SMBHs in the past 10 Gyr”

  • Evolution of M-L/M* relation (Treu+ 2007, Bennert+ 2010, 2011).
  • New approach for reverberation mapping. Geometric and dynamical models (Pancoast+ 2011, Brewer+ 2011)
  • Global robotic network of telescopes

Vestergaard – “Black hole demographics and mass estimates of high-­‐redshift AGN and quasars”

  • MV (2002, 2006, 2009): relationships between line properties and BH masses. The 2009 paper has BH mass functions but without Bayesian statistics to consider secondary effects.
  • Seeing BH population build-up?
  • BH mass estimates are too high?  See talks by Brandon Kelly and Priya.

Remco van den Bosch – “Supermassive black holes in compact galaxies”

  • Dynamical BH mass estimates. Need to resolve the “sphere of influence”. Restricted to D < 140 Mpc.
  • See slides on how to calculate the BH mass from HET+HST data. Trial potentials -> orbits -> reconstruct galaxy. Then search for optimal models.
  • NGC1277: 17e9 Msun BH in a M* = 1.2e11 Msun galaxy.
  • Concludes that it’s a old disk galaxy. No classical bulge (no co-evolution).
  • Many more of these types of galaxies.
  • MRK1216 is one example, but it is isolated.
  • Ultimate proof needs more resolution (AO).  0.05″ (10 pc).

Gregory Shields – “A captured runaway black hole in NGC 1277?”

  • Proposing an idea that a BH was ejected from the BCG (NGC 1275) and captured by this galaxy.
  • For a encounter with 300 km/s, the impact parameter of 10-30 kpc is needed for capture.
  • Probability of encounter in Hubble time in a rich cluster = 10%

Roger Blandford – “Massive black holes: Open questions”

  • Imaging a BH: Event Horizon Telescope (Doeleman+). For M87 and Sgr A*, need a resolution of 2 µas.
  • Would the B-field around a BH have a dipolar or quad. (ruled out by simulations, though) field?
  • Showing simulations by McKinney+. m=1 disk instability. Very cool volume rendering!
  • Observed jets are: fluid dynamical? continuous currents? poynting->pairs->plasma?Where do the current, flux, and helicity go?
  • Magnetoid acceleration: “spheromak”. Simplest example of helicity. Magnetically isolated structures. They have generic properties and have tremendous pressures inside of them, compared to the external pressure. They have a violent transition to lower energy states. Inductive EMF -> particle acceleration.

Notes from all previous talks were taken on my tablet. Sorry!

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