The relation among black holes, their host galaxies and AGN activity : The relation among black holes, their host galaxies and AGN activity Galaxies and Structures through Cosmic Times Venice, March 26-31, 2006 Alessandro Marconi
INAF-Osservatorio Astrofisico di Arcetri
In collaboration with … : 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)
Supermassive Black Holes : Supermassive Black Holes Supermassive BHs (106-1010 M) 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?
The Relation between Local Black Holes and AGN relics : 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)
The Local BHMF from MBH – Lbul/σe : The Local BHMF from MBH – Lbul/σe e.g. Salucci et al. 1998,
Marconi & Salvati 2001 e.g. Yu & Tremaine 2002, Black Hole Mass Function e.g. Ferrarese 2002,
Aller & Richstone 2003
The local Black Hole Mass Function : 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)
The AGN BH Mass Function : 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)
Local BHMF vs Relics BHMF : 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 Qso LF Hard-X LF Soft-X LF
X-ray Background constraints : 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.
Local BHMF vs Relic BHMF : 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= ε dM/dt c2)
λ=1 (L= λ LEdd)
Radiative Efficiency and Fraction of Eddington luminosity : 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
Local BHMF vs Relic BHMF : 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 …
Anti-Hierarchical BH growth : 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.
Conclusions : 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
Slide15 : Lbol/LEdd from the sample of SDSS quasars
(Mc Lure & Dunlop 2004)
Bolometric Corrections : Bolometric Corrections
MBH – host galaxy correlations : MBH – host galaxy correlations MBH- LSph (Kormendy & Richstone 1995, McLure & Dunlop 2002, Marconi & Hunt 2003)
MBH- MSph (Magorrian et al. 1998, Marconi & Hunt 2003, Häring & Rix 2004)
MBH- σe (Ferrarese & Merritt 2000, Gebhardt et al. 2000)
MBH-n (Sersic index, Graham et al. 2003)
They are still debated (few direct BH mass determinations, ~30-40, even less ~20 fully (?) reliable) but they are commonly taken as paradigms!
The MBH- σe / LSph /MSph relations:
Indicate close link between BH growth and galaxy evolution
Allow a demography of BHs
Duty cicle of active BHs : Duty cicle of active BHs δ is the fraction of Active BHs
δ = Φ( L, t) / N( MBH, t)
δ = 1 @ z=3 is the initial condition (negligible effect on BH Mass Function at z=0)
Gilli et al. M2 new
Total Lifetime of active BHs : Total Lifetime of active BHs MBH e-fold time (Salpeter’s):
To grow a BH SEVERAL tSalp needed: 7 × tSalp 103 106 M
14 × tSalp 103 109 M
tSalp independent of MBH, longer τBH at lower MBH indicates a more difficult growth of smaller BHs (feedback?).
Estimated AGN lifetimes range from 106 to 108 yr (AGNs from SDSS imply lifetimes > 108 yr; Miller et al. 2003). τBH~2 ×108 yr (>109 M) τBH~7 ×108 yr (<108 M)
Evolution of BH and stellar mass density : Evolution of BH and stellar mass density SFR ≈ 4000×BHAR See also Merloni, Rudnick & Di Matteo 2004
Consistency of MBH-Lbul and MBH-σe : Consistency of MBH-Lbul and MBH-σe MBH-Lbul and MBH-σe provide the same BHMF?
Check BHMF obtained with Φ(σ) and Φ(L) from the same sample [9000 E/S0 from SDSS; Bernardi et al, Sheth et al 2003]
Take into account intrinsic dispersion of correlations:
MBH-σ has rms ≤ 0.3 (Tremaine et al. 2002).
MBH-σ and MBH-Lbul have similar dispersion, rms ~0.3 (Marconi & Hunt 2003).