How Supermassive Black Holes Form by z ~ 7Daniel Whalen
Institute for Cosmology andGravitation
University of Portsmouth

Joe Smidt (LANL), Jarrett
Johnson (LANL), Hui Li (LANL)
Marco Surace (ICG), Sam
Patrick (ICG), Carla Bernhardt(Heidelberg)

Massive Quasars at z > 6• over 100 quasars have now been found at z > 6• ULAS J1120+0641 is a 2 billion M! SMBH atz = 7.1 (Mortlock et al. 2011, Nature, 474, 616)
• SDSS J010013.02+280225.8 is a 12 billion M!
BH at z = 6.3 (Wu et al. 2015, Nature, 518, 512) "• how do BHs this massive form 770 Myr after
the Big Bang?

SMBH Seed Formation Pathways

from Volonteri, ARAA, 2010, 18, 279

Direct Collapse Scenariosz ~ 15 – 20
Lodato & Natarajan 2006; Devecchi & Volonteri 2009)

Z~0

Z ~ 10-4 Z!

The Case for SMBH Seed Formationfrom “Normal” Pop III Star Collapse• super / hyper-Eddington accretion could create a 109 M! BH
from a 100 M! Pop III star BH, even at duty cycles of 1%(Madau et al. 2014, ApJ, 784, L38)
• but this process seems to require that infalling gas be at verylow angular momentum (Volonteri et al. 2015, ApJ, 804, 148)
• it remains to be understood why so few Pop III BHs grow inthis manner

The Case For SMBH Seed Formation
by Direct Collapse for z > 6 quasars• Pop III BHs are “born starving” (e.g.,Whalen et al. 2004)• current estimates of DCBH formation
rates account for quasars at z > 6(Dijkstra et al. 2008, Agarwal et al. 2015)

10510

410

3

10

2101

100

10

5104103

35.0
25.0
15.0
5.0

−1

10−1

100

101

radius (pc)

• a DCBH candidate, CR7, may now havebeen found (Sobral et al. 2015, Whalenet al. 2017)

10T (K)• low-mass Pop III BHs are often ejectedfrom their host halos (Whalen & Fryer
2012, ApJL, 756, 19)

n (cm−3)

X_e

2

10
1
100
10−110−210−310−410−510−610−710−810−910−101010

210

3

10−1100

10

110

210

3

10

4−5.0

radius (pc)

Whalen et al. 2004, ApJ, 610, 14

ionized gas velocity (km/s)• low-mass halos cannot retain gas
that is heated by x-rays (e.g., Parkand Ricotti 2011)

DCBH Candidate: CR7Sobral et al. 2015, ApJ, 808, 139

Dynamics of Catastrophic Baryon Collapse(Wise et al. 2008; Regan & Haehnelt 2009a,b; Latif et al 2013; Patrick +DJW 2017)

Supermassive Pop III Stellar Evolution
Hammerle + DJW+ 2017 MNRAS, in rev

Supermassive Pop III Stellar Mass at Collapse
Woods + DJW+ 2017 ApJL, acceptedCold Flows are also Key to Formation ofthe First Quasars(e.g. Di Matteo, DeGraf et al. 2012 ApJ, 745, L29)

SMBH Growth with Thermal Feedback in Massive BlackFeng et al. 2014, MNRAS, 440, 1865

Enzo Supermassive Black Hole
Formation Simulations
Smidt, DJW et al. 2017, ApJL in rev• 100 Mpc box, initialized at z = 200• x-ray emission from a 105 seed in a 5 x 108 solar mass halo at z ~ 19
• prescription for AGN disk wind is included (DeBuhr et al. 2010)• single photon energy of 1 keV – adaptive raytracing photon transportwith the MORAY radiation package• 10 levels of refinement, resolution of 30 pc• subgrid alpha disk model of accretion• multiphase star formation in host galaxy (SN)• stellar winds, ionizing UV and SN feedback due to SF in the hostgalaxy of the BH are included

H II Region of the Quasarz = 17z = 9.5z=7

Primordial Star Formation Regulates
SMBH Growth Rates from z > 1014 12Redshift

108

6

500

700
900
Time (Myr)51011

MBH (M O• )

1010

109

108

107
106
300

SMBH Mass

1100

SFR ~ 250 M! in the host galaxy
at z = 7.1, in agreement with obs(Barnett et al. 2015, A&A, 571, 33)

Mortlock Quasar Proximity Zone at z = 7.1

Metal and Dust Enrichment in the Host GalaxyThe metallicity in the host galaxy at z = 7.1 is approximately solar, inagreement with strong C lines (Dunlop 2013)

Synthetic Spectra for z = 7.1 Quasar
Surace, Whalen et al. 2017 in prep

Conclusions• x-ray feedback + wind/UV/SN feedback can account for theexistence of the Mortlock 2011 and Wu 2015 quasars• our prescription for SF feedback in the host galaxy
produces SFRs and metallicities consistent withobservations• our models reproduce all currently observed propertiesof J1120• next step is to calculate realistic synthetic observables
for the first quasars (NIR continuum, Ly-a, 21 cm)• soon perform ensemble studies of large numbersof 5 < z < 15 quasars to study the population at thisepoch