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Black Hole Masses and Accretion Rates Through the AGES

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Title: Black Hole Masses and Accretion Rates Through the AGES


1
Black Hole Masses and Accretion Rates Through the
AGES
  • Juna A. Kollmeier
  • Carnegie Observatories/Princeton University

In collaboration with Chris Onken (HIA), Chris
Kochanek, Andy Gould, David Weinberg, Matthias
Dietrich (OSU), Buell Jannuzi, Arjun Dey (NOAO),
Richard Cool, Daniel Eisenstein, Emeric LeFloch
(Steward)
2
Road Map
  • Why care about Supermassive Black Hole (SMBH)
    masses and feeding rates?
  • How to measure SMBH masses in halos far, far away
  • Results
  • Conclusions

3
Why SMBHs Matter for the Dark Sector
  • SMBH influence on DM profiles
  • Connection between SMBHs and DM halos/galaxies
  • Missing satellites
  • Primordial BHs made of DM?
  • Tracers of the dark sector (gravity waves)

4
The Galactic Center
  • Best case for BH in the universe
  • Measured directly from stellar orbits
  • Powering GR emission at the GC?

5
Galaxy Mergers
Simulated growth of BH and galaxies Courtesy
Tiziana DiMatteo, V. Springel 2003
Connection between ULIRGs AGN Sanders et al.
1988, ApJ, 328,35
6
The M-? Relation
Ferrarese 2002
Tight correlation between BH mass and bulge
velocity dispersion.
7
The MBH-Mhalo Relation
  • Ferrarese 2002 Suggests a very tight relation
    between the DM halo and the black hole mass.
  • How is this set up?

8
What We Should Figure Out
  • What is the range of black hole masses out there?
  • What is the range of accretion rates?
  • How do these objects affect their environments
    (light and dark)
  • How is the tight connection between SMBH mass and
    halo/bulge mass established?
  • DM tells black hole how big to be?
  • Black hole tells stars how to behave?

9
BH mass measurements
  • Measure velocity dispersion of stars moving
    around BH
  • Measure velocity of water masers moving around BH
  • Measure velocity of gas moving around BH
  • Measure response of broad line material to
    continuum changes (reverberation mapping)

10
Reverberation Mapping
  • Trade spatial resolution for time resolution!

11
The Virial Product
Measure the width of the broad lines from
spectrum --gt V
Measure the time delay from light curve--gt
c??????R
M R V2
12
R-L relation
If you cant measure a time delay to get the
broad line region size, you can use an empirical
relation (calibrated using RM) between luminosity
and BLR size. Then you only need measure
luminosity!
Kaspi et al. 2005
13
Estimating Black Hole Masses
M V2 R R Lb
Hb (a,b) 0.68, 0.61 (McLure Jarvis
2002) CIV (a,b) 0.20, 0.7 (Vestergaard
2002) MgII (a,b) 0.24, 0.91 (recalibrated)
The pundits This method is fraught with
uncertainty. The students Its all weve
got!
14
AGN and Galaxy Evolution Survey
  • Multi-wavelength coverage over 9 deg2
  • X-ray Xbootes
  • Optical NDWFS Hectospec
  • IR Spitzer
  • Deep! Limiting optical magnitude is R21.5 for
    spectroscopy!
  • Sources are 24?m or X-ray selected Broad Lined
    AGN
  • 4 counts in Chandra 5 ks observations
  • brighter than 1 mJy at 24?m AND
    J-band magnitude gt 12log(F24?m) (i.e.
    NOT stars)
  • ?733 AGN

15
AGES
AGES in SDSS
16
Not all Spectra are Usable
  • Start with 733, eliminate 326
  • low S/N or other measurement problems (119),
  • FeII emission (70),
  • broad absorption features (130)
  • leaves 407 no obvious differences in
    luminosity/redshift distribution of the dropped
    objects and the remaining objects

17
Luminosity Function

Want to Probe the knee
a1
a2
From Steed Weinberg 2003
For a1, a2 gt - 2, the action is around the knee
18
AGES Advantage Depth
Knee!
From Kollmeier, Onken, et al. 2006, ApJ, 648, 128
19
Mass and Luminosity
From Kollmeier, Onken, et al. 2006, ApJ, 648, 128
20
Eddington Ratio at Fixed Luminosity
  • In each bin the distribution looks Gaussian with
    dispersion
  • 0.3 dex!
  • has contribution from measurement method
    scatter

Kollmeier, Onken, et al. 2006, ApJ, 648, 128
21
Distribution of Eddington ratios at fixed black
hole mass
Where we have enough dynamic range, we also see
that the distribution of Eddington factors at
fixed black hole mass is sharply peaked near
unity ?luminous quasars all accrete close to
their limiting accretion rate
Dashed raw Solid completeness corrected Arrow
where optical flux limit begins to
matter Dashed below optical flux limit
22
The Peaks
In some bins, we are not affected by
selection! There is a very tight distribution of
Eddington ratios at fixed mass for these objects!
From Kollmeier, Onken, et al. 2006, ApJ
23
Summary
  • BH masses for 407 AGN in the AGES surveys
    measured!
  • Distribution of Eddington ratios for these
    objects is surprisingly uniform and narrow!
  • Where we can make the measurement, the
    distribution of accretion rates at fixed MASS is
    also narrow
  • When black holes are on, they are ON!

24
To Do
  • More BH masses! Currently measuring SMBHs in the
    2QZ survey and AGESII (Onken et al. in
    preparation)
  • Extend analysis to lower masses/luminosities and
    see what happens to the peaks
  • Clustering of SMBHs --gt determine host halo
    masses
  • Test simulations of BH growth
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