1. The Growth of Supermassive Black Holes
around 1 Gyr After the Big Bang
From Black Hole to Environment
22 August 2017
Christian Wolf & Fuyan Bian (ANU)

2. High-redshift Quasars
Existence of Supermassive black holes at the early epoch of the Universe.
SMBH accretion history in the Universe.
Relation of BH growth and galaxy evolution.
Quasar at z=7.1 Mortlock+2011
[CII] emission from quasar host galaxy
Venemans+2015
Quasar number density
redshift

3. High-redshift Quasars
Wu+2015
High-redshift Quasars
Black hole mass
Ryan-Webber+2009
Fan+2006
Intervening absorption systems
Gunn-Peterson trough
Neutral Hydrogen in IGM

4. SMBHs 1 Gyr After Big Bang
Time since Big Bang in million years
Today
log BH mass / billion MSun
known BHs
Eddington growth from 100 Msun seed BH
1 million Msun seed BH
100 million Msun seed BH
Super-Eddington growth …
M87
Eddington t10× = 450 Myr (radiative efficiency 0.5)

5. SMBHs 1 Gyr After Big Bang
Time since Big Bang in million years
Today
log BH mass / billion MSun
known BHs
Eddington growth from 100 Msun seed BH
1 million Msun seed BH
100 million Msun seed BH
Super-Eddington growth …
M87
Radiatively inefficient super-Eddington accretion, but
wherever seen radiatively inefficient accretion goes with low accretion rates (radio mode)
Black-hole mergers
galaxy merger rates
Primordial direct collapse

6. Bayesian Candidate Selection
Wolf+ 2003
Reed+ 2017
Role of
priors?
Wang+ 2016

7. Massive Black Holes at High Z
Number count priors?
Bright objects 99% stars
QSO
stars
mag
12bn z=6.3
Wu+ 2015

8. Planned Work With SkyMapper

9. z~4.6 QSO in SkyMapper EDR
E.g.: SkyMapper (Shallow Survey EDR) + 2MASS + WISE Crucial for complete identification: cost of spectroscopic follow-up

10. TAIPAN Only 6 QSOs known at z>5, >4bn M, but 50 may exist
Refurbished UK Schmidt Telescope
Two million galaxy spectra
All Southern Sky
Yrs PIs: Hopkins & Colless
Ancillary Science Programme 1$ per fibre
10,000 cool stars bright QSOs at z = [4.5,5.7]
PIs: Wolf, Bian & Fan

11. Planned Work With SkyMapper
known BHs
accessible to SkyMapper
100 million Msun seed BH
M87
log BH mass / billion MSun
1 million Msun seed BH
Super-Eddington growth
Eddington growth from 100 Msun seed BH
Time since Big Bang in million years …
Today
Black-hole mass functions (BH MF) in z/t bins complete at bright end – watch BH MF grow

12. SkyMapper Southern Survey Data Release 1
see SkyMapper Talk
Wed 23 August

13. SkyMapper DR1: Coverage
20,200 deg2, 3 visits in uvgriz
2.3 billion detections in 68,000 images
320 million unique astrophysical objects
Shallow Survey, complete to 18m

14. Deeper Main Survey Data
DR2 in Jan 2018:
Main Survey data with gr to 22m, i/z to 21m/20m
i/z-band coverage 90% complete
Entirely sufficient for all QSOs at z > 5.7
Need deep r-band for dropouts at 4.7 < z < 5.7
PanSTARRS DR1 at >-30°
SM deep uvgriz coverage
35% now
Finish by 2020
SkyMapper Main Survey: June 2017

15. Conclusion
SkyMapper+TAIPAN provides an ideal machine to search for luminous quasars at z>4.5.
Build up a complete sample of quasars at the bright end.
Study the early supermassive black hole growth.

17. Reionisation QSOs good probes
Insufficient UV photons to be main cause (30% of starlight)
Fan, Carilli & Keating 2006

18. Meanwhile at Low Redshift
NASA/ESA
ESO/MPG/NASA
ESO

19. Possible Scenarios
Radiatively inefficient highly super-Eddington accretion, but
wherever seen radiatively inefficient accretion goes with low accretion rates (radio mode)
at peak of cosmic activity QSO accretion mostly at low Eddington ratios
Primordial direct collapse
Black-hole mergers
galaxy merger rates

20. DR1 Photometry of Globular Cl
DR1 photometry of red giants in outer regions of globular cluster NGC compared with Stetson data of photometric standards and 12.5 Gyr Dartmouth isochrones at metallicity -2.0/-2.5 (lines)

21. DR1 Photometry of Globular Cl
DR1 photometry of red giants in outer regions of globular cluster NGC compared with Stetson data of photometric standards and 12.5 Gyr Dartmouth isochrones at metallicity -2.0/-2.5 (lines)