A synthesis model for AGN evolution: unveiling SMBH growth with (past and future) X- ray surveys Ringberg Meeting, 2/2008 Andrea Merloni Max-Planck Institut für Extraterrestrische Physik Garching, Germany

This talk: What do we know about evolution of SMBH population (mass function, accretion rates, etc.) A lot! (up to z~4-5) Evolution of mass and accretion rte density Constraints on radiative efficiency and avg. BH spin Anti-hierarchical evolution (downsizing) Where are the frontiers? Obscured AGN High-z AGN, first BH Iron line spectroscopy: spin evoluton

Black Holes in the local Universe Ω SMBH ≈2.7  Ω *BH ≈7  [Fukugita & Peebles (2007)] Sgr A*M87 Stellar physics, SN explosions, GRB Accretion over cosmological times, Active Galactic Nuclei, galaxy evolution Ω baryon ≈4.5  ; Ω stars ≈2.5  Density of stellar mass BHs increases w/galaxy mass Metallicity evolution may cause a shift in the typical BH mass How does the high- mass (Supermassive) peak grow?

(Silverman et al. 2007) Solid lines: mod. PLE Dotted lines: LDDE Corrected for absorption with Gilli et al N H distribution (including Compton Thick sources) 2-10 keV Luminosity Functions of AGN

AGN and Cosmology: a shift of paradigm Merloni and Heinz 2008 Hopkins and Beacom (2006)

Note: radiative efficiency vs. accretion efficiency Non Spinning BHMaximally Spinning BH radiative efficiency accretion efficiency (BH spin) Determined by the complex physics of gas accretion

Integral constraints BHAR(z) = (Normalized SMBH mass density) Soltan (1982) first proposed that the mass in black holes today is simply related to the AGN population integrated over luminosity and redshift

Constraints on avg. radiative efficiency  rad  Merloni and Heinz 2008  0 =  BH,0 /(4.2x10 5 )  i =  BH (z=z i )/  BH,0 (Input from seed BH formation models needed!) Begelman & Rees: Gravitiy’s fatal attraction 0.065/[  0 (1+  lost )]  rad  0.069/[  0 (1-  i +  lost )]  lost =  BH,lost /  BH,0 (Mass density of SMBH ejected from galactic nuclei due to GW recoil after mergers)

Constraints on avg. SMBH spin  a*  0.065/[  0 (1+  lost )]  rad  0.069/[  0 (1-  i +  lost )]

Constraints on avg. SMBH spin  a*  ( SMBH more easily ejected If avg. spin higher

AGN/SMBH downsizing: clues from X-rays Ueda et al. 2003; Fiore et al. 2003; Barger et al. 2005; Hasinger et al AGN downsizing

Cavaliere et al. (1973); Small & Blandford (1992); Marconi et al. (2004) Continuity equation for SMBH growth 1- Need to know simultaneously mass function  M (M,t 0 ) and accretion rate distribution 2- At any z (or t), it is possible to combine mass function and bolometric luminosity function to calculate accretion rate distribution Picture from Di Matteo et al. (2007)

Merloni and Heinz Solved continuity equation backwards in time Mass function must get narrower with z L/L edd function gets wider

The anti-hierarchical evolution at low z seems reversed at high z Heckman et al ~ 3 Log M BH 23,000 type 2 AGN at z<0.1 Growth Time SMBH downsizing

Merloni and Heinz (2008) Radiated energy density by BH mass We can follow the history of progenitors of local black holes

“Active” BH Mass Functions/ Number counts Consequences of broad accretion rate distributions: Number density and mass functions of AGN are very sensitive to survey selection function Merloni and Heinz (2008)

“Active” BH Fractions/Mass Sensitivity curves Consequences of broad accretion rate distributions: Number density and mass functions of AGN are very sensitive to survey selection function The concept of “active” BH must be defined observationally Merloni and Heinz (2008)

Based on the current XRB synthesis models and N H distribution, we can trace evolution of SMBH mass density Tight constraints on radiative efficiency and avg. spin Couple spin evolution and ‘seed’ BH distribution SMBH grow with a broad accretion rate distribution The anti-hierarchical trend is clearly seen in the low-z evolution of SMBH mass function. Reversal at higher z? Conclusions

eROSITA questions Tighten N H (z,L) Bolometric corrections: SED variance Symbol X questions Where are the Compton Thick AGN? Spin properties of AGN from iron line spectroscopy XEUS question Seed Black holes distribution Open questions