The relation among black holes, their host galaxies and AGN activity

1. ISTITUTO NAZIONALE DI ASTROFISICA NATIONAL INSTITUTE FOR ASTROPHYSICS INAF The relation among black holes, their host galaxies and AGN activity Alessandro Marconi INAF-Osservatorio Astrofisico di Arcetri Galaxies and Structures through Cosmic TimesVenice, March 26-31, 2006

2. In collaboration with … • Andrea Comastri (INAF – Bologna, I) • Roberto Gilli (INAF – Bologna, I) • Günther Hasinger (MPE, Garching, D) • Leslie Hunt (INAF – IRA, Firenze, I) • Roberto Maiolino (INAF – Arcetri, Firenze, I) • Guido Risaliti (INAF – Arcetri, Firenze, I) • Marco Salvati (INAF – Arcetri, Firenze, I)

3. Supermassive Black Holes • Supermassive BHs (106-1010M) are detected in 30-40 NEARBY (D<100 Mpc) galaxies (e.g. Ferrarese & Ford 2005). • MBH correlates with Lsph/Msph (Kormendy & Richstone 1995, Magorrian et al. 1998, McLure & Dunlop 2002, Marconi & Hunt 2003) and σe (Ferrarese & Merritt 2000, Gebhardt et al. 2000). • Supermassive BHs likely present in all galaxies. • Supermassive BHs are also expected as “Relics” of AGN activity. • Are the local supermassive BHs consistent with being AGN relics?

4. The Relation between Local Black Holes and AGN relics • Compare the mass density of local BHs with that of AGN relics (e.g.Soltan 1982, Fabian & Iwasawa 1999, Elvis, Risaliti & Zamorani 2002) • Compare the local BH Mass Function with the mass function of relic BHs (e.g. Yu & Tremaine 2002, Ferrarese 2002, Marconi et al. 2004, Merloni 2004, Shankar et al. 2004)

5. Galaxy Luminosity Function per Morphological Type Galaxy Velocity Function + Bulge/Total correction (SDSS, Sheth et al. 2003) + Faber-Jackson relation Bulge (Spheroid) Luminosity Function + MBH-σe relation + MBH-Lbul relation The Local BHMF from MBH – Lbul/σe Black Hole Mass Function e.g. Salucci et al. 1998, Marconi & Salvati 2001 e.g. Ferrarese 2002, Aller & Richstone 2003 e.g. Yu & Tremaine 2002,

6. The local Black Hole Mass Function • Using MBH-Lbul and MBH-σe provide consistent BH mass functions (differences included in shaded area which indicates uncertainties) • ρBH≃ 4.1+1.9-1.4 ×105 M Mpc-3 (cf. Merritt & Ferrarese 2001, Ferrarese 2002, Shankar et al. 2004) • In summary: 3-5 ×105 M Mpc-3(see Ferrarese & Ford 2005 for a review)

7. The AGN BH Mass Function • Assume accretion onto BH as powering mechanism of AGN to link LAGN with MBH [L= λ MBHc2/tE= ε (dM/dt)c2] • Use the continuity equation (Cavaliere et al. 1971) to relate the BH Mass function N(MBH) to the AGN Luminosity function Φ(L) • Critical issues: • L is the TOTAL accretion luminosity • Φ(L) is the luminosity function of ALL AGNs (observations provide Φ only for a subset of the AGN population)

8. Local BHMF vs Relics BHMF • The relic BHMF is a function of the band in which AGN are selected. • Even the hard (2-10 keV) XLF does not sample the whole AGN pop • Heavily obscured Compton-thick AGN are missing X-ray background spectrum Hard-X LF Soft-X LF Qso LF

9. X-ray Background constraints • XRB models provide the total numbers of Compton-thin + Compton-thick AGN • Two options explored: • M1: R = obscured/unobscured AGN ratio = constant • M2: R decreasing with luminosity Gilli, Comastri, Hasinger 2006 in prep.

10. Local BHMF vs Relic BHMF • Correction for Compton-Thick sources from XRB models  whole AGN pop considered • The only free parameters are the accretion efficiency and Eddington ratio • Assume: • ε=0.1 (L= εdM/dt c2) • λ=1 (L= λ LEdd)

11. Radiative Efficiency and Fraction of Eddington luminosity • Efficiency and fraction of Eddington luminosity are the only free parameters! • Determine locus in ε-λ plane where there is the best match between local and relic BHMF! • ε=0.04-0.10 λ=0.08-0.5 which are consistent with common ‘beliefs’ on AGNs

12. Local BHMF vs Relic BHMF • Local and Relic BHMFs are in agreement without considering merging. • Either merging of BHs is negligible for z<3 or it does not modify significantly the BHMF (e.g. Granato et al. 2004, Menci et al. 2004, Haiman, Ciotti & Ostriker 2004). with best ε and λ values …

13. 50% of final mass Anti-Hierarchical BH growth • This is qualitatively consistent with models of galaxy formation (e.g. Menci et al. 2003, Granato et al. 2003) • Big BHs form in deeper potential wells  they form first. • Smaller BHs form in shallower potential wells and are more subjected to feedback effects (star form., AGN),  they form later and take more time to grow. • See also Merloni 2004.

14. Conclusions • The local BH mass density is ρBH = 4.1±1.5 ×105 M Mpc-3. • The local BH mass function and the BH mass function of AGN relics are in good agreement with standard ε and λ values (ε ~ 0.1, λ ~ 1.0). • Merging of BH’s either is not important or it does not significantly alter the relic BHMF, at least at z<3. • The BH growth is anti-hierarchical: smaller BH’s, MBH< 107 M, grow at lower redshifts, z<1, with respect to more massive ones, z=1-3. • Local BH's grew during AGN phases in which accreting matter was converted into radiation with ε = 0.04-0.1 and emitted at a fraction λ = 0.08-0.5 of the Eddington luminosity. Marconi et al. 2004, 2006 in preparation