DIRECT COLLAPSE BLACK HOLES AS SEEDS OF QUASARS AT REDSHIFT > 6. Bhaskar Agarwal TMoX Group Max Planck for Extraterrestrial Physics!!

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1 DIRECT COLLAPSE BLACK HOLES AS SEEDS OF QUASARS AT REDSHIFT > 6 Bhaskar Agarwal TMoX Group Max Planck for Extraterrestrial Physics!! OPINAS Seminar, 30 April 2014

2 PROBLEM Explain supermassive black holes at z>6 (Fan et al., Mortlock et al., etc.) Structure: stars/galaxies/bhs only had 800 Myr to evolve (Tegnermark et al. 97) Cosmic Variance to the rescue? A scenario that does not depend on Cosmic Variance

3 OUTLINE Introduction Part I Semi-analytical model (Agarwal et al. 2012) Existence Part II FiBY simulation (Agarwal et al. 2014) Part III A new class of galaxies? (Agarwal et al. 2013) Evolution Summary

4 FIRST STARS AND GALAXIES First Stars and Galaxies z~20-30, t ~ 200 Myr First Generation of stars Population III: M sun First stellar black holes: ~100 M sun t ~ 650 Myr to grow from 10 2 to 10 9 M sun H2 200K K Tvir < 10,000 K Typical Mass: 10 6 Msun H ,000 K Requires: - constant accretion at fedd =1 - massive gas reservoir - Cosmic variance to the rescue! H Tvir > 10,000 K Typical Mass: 10 7 Msun

5 MAKING THE FIRST STAR

6 LYMAN WERNER RADIATION LW: ev Dissociate H2 molecules: basic constituents of first galaxies/halo J or JLW in units: erg/ s/ Hz/ cm 2 / sr Enough LW Radiation H2 + {LW} H2 Delay Pop III Star formation H2 H + H Tvir < 10,000 K

7 LYMAN WERNER RADIATION LW: ev Dissociate H2 molecules: basic constituents of first galaxies/halo J or JLW in units: erg/ s/ Hz/ cm 2 / sr Critical (high) LW Radiation H H H2 Stop Pop III Star formation H + H H Tvir > 10,000 K 8000

8 MAKING A DCBH Pop III n = 10 5 cm 3 T = 200 K DCBH n = 10 5 cm 3 T = 8000 K M BE ~ 100 M sun M BE ~ 10 5 M sun

9 CREATING SMBH BY Z=6 Stellar Black Holes Direct Collapse Single 100 Msun Merged 10 4 Msun NO H2 Gas/Time For Acc.?? Merging: > Timescale > Slingshots NO fragmentation Msun

10 THEORETICAL MODELS: EXISTENCE PART I & PART II SAM Agarwal et al FiBY Dalla Vecchia et al. Cosmological Volume Yes Yes Minihaloes resolved Yes Yes Halo histories Yes Yes Outflows Yes Yes Pop III + Pop II Yes Yes LW radiation: Spatial + Global Yes Yes Gas No Yes IGM Metal Dispersion No Yes

11 SEMI ANALYTICAL MODEL PART I: SAM

12 HOW THE MODEL WORKS PART I: SAM Metal Free Pop III Polluted Pop II DCBH LW LWcrit Mhot Mhot tdyn tdyn Mcold Mcold tdyn tdyn Mhot Mhot Outflows Outflows

13 DC SITES How many such sites exist at z>6 What is so special about these sites? What about their past, history of the halo/galaxy? How many such sites make a DCBH? How do they evolve?

14 HOW MANY DC SITES? PopII J max PopII J bg PopII J crit PopIII J max PopIII J bg PopIII J crit J bg 10 2 J LW z Agarwal et al. 2012

15 HOW MANY DC SITES? DC sites: Few (<10) at z>6 in a ~100 cmpc 3 box Quasars: few / Gpc 3 at z>6!! log(dn/dz) [Mpc 3 ] 2.0 esc esc DC seems to be more probable than previously thought esc Agarwal et al. 12 vs. Dijkstra et al esc0.5hsfe! 2.5! Discrepancy: 10 7 objects too many! (?) esc0.5reion z Agarwal et al. 2012

16 DC SITES How many such sites exist at z>6 What is so special about these sites? What about their past, history of the halo/galaxy? How many such sites make a DCBH? How do they evolve?

17 DC SITES: WHAT IS SO SPECIAL? z= Steeper Two point correlation , , z= DC sites prefer a more clustered neighbourhood Halo(DC) / Halo(NoDC) , , Need to be close to a larger z= galaxy giving out critical LW flux , , log(d phy ) [pc] Agarwal et al. 2012

18 FIBY SIMULATION PART II: FIBY COURTESY: CLAUDIO DALLA VECCHIA

19 DC SITES: WHAT IS SO SPECIAL? PART II: FIBY Y [phy. kpc] Z [phy. kpc] X [phy. kpc] Log J LW,II X [phy. kpc] Y [phy. kpc] Z [phy. kpc] Y [phy. kpc] 0-10 Z [phy. kpc] 0-10 Y [phy. kpc] Log Z sun X [phy. kpc] Y [phy. kpc] X [phy. kpc] Agarwal et al. 2014

20 DC SITES: WHAT IS SO SPECIAL? Y [phy. kpc] Z [phy. kpc] X [phy. kpc] Log J LW,II X [phy. kpc] Y [phy. kpc] Z [phy. kpc] Y [phy. kpc] 0-10 Z [phy. kpc] 0-10 Y [phy. kpc] Log Z sun X [phy. kpc] Y [phy. kpc] X [phy. kpc] Agarwal et al. 2014

21 DC SITES How many such sites exist at z>6 What is so special about these sites? What about their past, history of the halo/galaxy? How many such sites make a DCBH? How do they evolve?

22 DC SITE: HISTORY DC3 The DC site: ON08 J LW,II J LW,III J LW,Total J LW avoids Pop III SF in its past remains unpolluted redshift - happens to be exposed to Jcrit when it becomes atomic cooling M DM [M sun ] T vir =10000 K T vir =2000 K redshift Agarwal et al. 2014

23 DC SITE: MERGER HISTORY 30 first prog. next prog first prog. next prog first prog. next prog DC0 at z=10.50 DC2 at z=9.65 DC2 at z= redshift 7.50 Log(M DM ) [M sun ] redshift 7.50 Log(M DM ) [M sun ] redshift 7.50 Log(M DM ) [M sun ] Agarwal et al. 2014

24 DC SITES How many such sites exist at z>6 What is so special about these sites? Part I & II What about their past, history of the halo/galaxy? How many such sites make a DCBH? How do they evolve? Part III

25 - Atomic cooling halo, T > 8000 K - Metal Free - LW flux: critical value exceeded MAKING A DCBH! Avoid fragmentation and cooling to make Pop III stars - Supermassive Star: turbulence vs. low angular momentum Latif et al. 2013, Wise et al. 2008! - Nested instabilities: bars within bars to shed angular momentum Volonteri et al Low spin disc: to relate the DM-halo spin to gas angular momentum Agarwal et al Lodato and Natarajan 06/07 Strictly an upper limit!

26 GROWTH OF A DCBH DCBH Merger In Situ Pop III Star Pop II Cluster Empty halo Growth of BH ± Stars

27 GROWTH OF A DCBH Metal Free Pop III Polluted Pop II DCBH Outflows Mhot LW Mhot Mhot LWcrit tdyn Mcold DCBH tdyn tdyn Mcold tdyn Mcold tdyn OBG Phase Mhot flim Mhot Outflows Mcold + Mhot Outflows

28 A NEW CLASS OF OBJECTS? Galaxies where a massive seed BH forms first! Stellar component forms later! BH ends up being obese and LBH > Lstar! Obese Black Hole galaxies: OBG! OBGs have distinct observational features

29 GROWTH OF DCBH: OBG M BH [M O ] O1, z g =6.18 O2, z g =8.93 O3, z g =7.34 O4, z g =6.55 f edd = f lim = 1.5 f lim = 0.75 f lim = M * [M O ] Agarwal et al. 2013

30 OBSERVING OBG Rest wavelength [Å] O1 O2 O3 O4 f lim = 1.5 f lim = 0.75 f lim = m AB Observed wavelength [Å] Agarwal et al. 2013

31 OBSERVING OBG Agarwal et al. 2013

32 SUMMARY Possibility of DCBHs at z>6: higher than previously thought DCBHs form in satellites: mergers could lead to MBH -Mbulge A new class of galaxies at z>6: obese black hole galaxies [OBG] Observational signatures at z < 6 (Rosario, Agarwal in prep) Revision in theories of DCBH formation (Agarwal et al. in prep) Impact of reionisation (Johnson, Whalen, Agarwal et al. in prep, Paardekoper, Agarwal et al. in prep) Impact on reionisation (Paardekooper, Agarwal et al. in prep) Where do they end up : satellites or centrals?

33 %&'($)"(*+#, %&'($)"(*+#,!"#$%&'($)"(*+#, ;$$<$>555$=!"#$%&'($)"(*+#, $56557$$$$$5657$$$$$5657$$$$$567$$$$$$$$7$$$$$$$$$$$$$666$$$$$$$$$$$$$$$$ !"...(JLW)... Jcrit JLW in units: erg/ s/ Hz/ cm2/ sr Oxford GEDG Seminar March :#$% ;$$<$758555$= +(. 0' /&$0 #4 " +4 11'2 '& 3..$ DC SITE: HISTORY