Black Holes in Galaxies and Black Holes in Galaxies and Globular ClustersGlobular Clusters

The Current Status of Supermassive Black Hole Detections Scaling Relations and SBH Demographics Missing Pieces and Prospects for Future Progress

Laura Ferrarese (Rutgers University)

Resolution is the KeyResolution is the Key With the exception of the Iron K observations, every other technique used to

measure supermassive black holes masses probes regions well beyond the strong field regime.

Method Distance fromcentral sourceÿ

No. of SBHDetections

Mass Range(M

§)

Typical Densities(M

§ pc-3)

X-Ray Fe K(XEUS,ConX)

3-10 RS 0 N/A N/A

Broad-Line Region(Ground-basedoptical)

600 RS 36 10 6−4×10 8 > 10 10

Proper Motion (M )W(Ke ckNTT, VLT)

1000 RS 1 4×10 6 4×10 16

Megamasers(VLB )I

4 ×10 4 RS 1 4×10 7 >10 12

Gas Dynamics(Mostl y HST)

8 ×10 5 RS 11 7×10 7−4×10 9 ~105

Stellar Dynamics(Mostl y HST)

10 6 RS 17 10 7−3×10 9 ~105

In units of the Schwarzschild radius RS = GM/c2 = 1.5 1013 M cm .

Proper Motion in the Galactic Proper Motion in the Galactic CenterCenter

Schodel et al. 2003; Ghez et al. 2003

The most recent measurements exclude with high confidence that the central dark mass could consists of a cluster of unusual stars or elementary particles, leaving a supermassive black hole as the only viable possibility.

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H20 Megamasers in NGC 4258H20 Megamasers in NGC 4258 VLBI 1.35cm observations; Resolution: =0.00060.0003, v= 0.2 km s-1

o Only 4% of Seyfert 2s host H20 megamasers (Braatz et al. 1994 & 1996; Greenhill et al. 1997, 2002 & 2003). Of these only a small (~20%) fraction exhibit high velocity masers.

+M51, NGC1068, NGC3079, NGC4945, NGC5793, NGC6240, IC2560, Mrk348, Mrk1419, Circinus

o Of these, only N4258 has so far yielded a conclusive detection (Greenhill et al. 1996, 1997, Trotter et al. 1998)

Miyoshi et al. 1995

0.13 pc

0.26 pc

M ~ 4 107 M

h = 1012 M pc-3

Kinematics of Nuclear Dust DisksKinematics of Nuclear Dust Disks Nuclear dust/gas disks are present in ~20% of Early-Type galaxies (Tran et al. 2001;

Ferrarese et al. 2004)

The ACS/Virgo Cluster Survey Collaboration, Côté et al. 2004

Kinematics of Nuclear Dust DisksKinematics of Nuclear Dust Disks Ferrarese et al. 1994; Macchetto et al. 1997; Bower et al. 1998; van der Marel & van

den Bosch 1998; Ferrarese & Ford 1999; Verdoes Kleijn et al. 2000; Marconi et al. 2001; Barth et al. 2001; Sarzi et al. 2001; Devereux et al. 2003; Tadhunter et al. 2003.

Attempts to apply the method to spiral galaxies are underway (Marconi et al. 2003; Sarzi et al. 2001; Coccato et al. 2004 - see poster by Elena Dalla Bontá et al.)

Ford et al. 1994; Harms et al. 1994

Spatial resolution 0.1 with HST

Gas emission lines are easy to measure

Failure of the models is easily recognizable (Cappellari et al. 2002; Barth et al. 2001; Marconi et al. 2003)

Dust disks are detected only in active galaxies

Disk geometry (warps, etc.) needs to be constrained.

Turbolence, asymmetric drifts and instrumental effects must be taken into account (Verdoes & Klejin et al. 2000, Barth et al. 2001, Maciejewski & Binney 2001)

The disks must be in Keplerian motion: 2D velocity maps are essential

Macchetto et al. 1997

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The ACS/Virgo Cluster Survey Collaboration, Côté et al. 2004

Stellar DynamicsStellar Dynamics Emsellem et al. 1999; Cappellari et al. 2002, Gebhardt et al. 2003

Spatial resolution 0.1 with HST Stellar kinematics is always

gravitational 3I models provide a general

description of the stellar system (Verolme et al. 2002; Gebhardt et al., Valluri et al. 2004).

The galaxy’s inclination angle is generally assumed a priori.

Axysimmetry is assumed (but see vanden Ven 2003)

2D velocity maps are rarely available.

The stellar M/L ratio is assumed constant.

Systematics are not well understood (Valluri et al. 2004; Richstone et al. 2004).

The sphere of influence is not always resolved

Ferrarese & Ford 2004

Stellar DynamicsStellar Dynamics Emsellem et al. 1999; Cappellari et al. 2002, Gebhardt et al. 2003

Spatial resolution 0.1 with HST Stellar kinematics is always

gravitational 3I models provide a general

description of the stellar system (Verolme et al. 2002; Gebhardt et al., Valluri et al. 2004).

The galaxy’s inclination angle is generally assumed a priori.

Axysimmetry is assumed (but see vanden Ven 2003)

2D velocity maps are rarely available.

Systematics are not well understood (Valluri et al. 2004; Richstone et al. 2004).

Importance of resolving the sphere of influence not recognized (Merritt & Ferrarese 2001; Marconi & Hunt 2003; Graham et al. 2001 vs Kormendy & Gebhardt 2001; Richstone et al. 2004).

Rinfl ≈11

MBH /108M8

(σ /200kms−1)2parsecs

Scaling RelationsScaling Relations

€

logMBH

M8

= (−0.36 ± 0.09)BT0 + (1.2 ±1.9)

χ r2 = 23

Kormendy & Richstone 1995

€

MBH

M§

= (1.7 ± 0.3) ×108 σ c

200km s−1

⎛

⎝ ⎜

⎞

⎠ ⎟

4.6±0.5

χ r2 = 0.72

Ferrarese & Merritt 2000; Gebhardt et al. 2000

logvc =(0.84±0.09)logσ +(0.55±0.19); χr2 =0.4

The MThe M - M - MDMDM Relation Relation

M•

108M§~0.046

MDM

1012M§

⎛

⎝ ⎜ ⎜

⎞

⎠ ⎟ ⎟

1.57

Ferrarese 2002; Baes et al. 2003; Pizzella et al. 2004 (but see also Franx 1993; Wyse, Gilmore & Franx 1997)

Applicability of the MApplicability of the M Relation Relation “Primary Mass Calibrator” for non-standard methods of estimating masses (e.g.

reverberation mapping, Ferrarese et al. 2001; Onken et al. 2004)

Estimating individual masses - 30% accuracy (Barth et al. 2002; Falomo, Kotilainen & Treves 2002; Marchesini et al. 2004).

Constrain models and numerical simulations following the formation and evolution of SBHs (Silk & Rees 1998; Haehnelt, Natarajan & Rees 1998; Kauffmann & Haehnelt 2000; Adams, Graff & Richstone 2000; Haehnelt & Kauffmann 2000; Burkert & Silk 2001; Ciotti & van Albada 2001; Fabian et al. 2001; Portegies-Zwart & McMillan 2002; MacMillan & Henriksen 2002; Zhao et al. 2002)

Study SBH demographics

Method Redshift

(105 M Mpc-3)

Reference

QSO Optical counts

0.3 < z < 5.0

2 4 Ferrarese 2002, Yu & Tremaine 2002, Salucci et al. 1999

AGN X-ray population counts

z(peak) ~ 0.7

~ 2 Fabian (2003), Cowie (2003)

Local AGNs z < 0.1 0.05 0.6 Padovani et al. 1990; Ferrarese 2002

Local Quiescent Galaxies

z < 0.03 2.5 5 Ferrarese 2002; Yu & Tremaine 2002, Aller & Richstone 2002, Wyithe & Loeb 2003

SPIRALS

ELLIPTICALSLENTICULARS

Outstanding IssuesOutstanding Issues

Despite the progress made in the past few years, systematics have not been fully investigated. These include:

Slope, zero point and scatter of SBH scaling relations

Dependence on Hubble type

Dependence on galaxy environment

Cosmic evolution of SBH scaling relations

Andromeda, NGC 205 and M32 1.5 X 2 degreesNGC205 - HST/ACS/HRC - 29X29 arcsec

The Low Mass End of the SBH Mass The Low Mass End of the SBH Mass Function Function

3I models applied to the NGC 205 kinematics (Valluri et al. 2004)

M(BH) = 0 MM(BH) = 104 M

M(BH) < 5104 M

The Low Mass End of the SBH Mass The Low Mass End of the SBH Mass FunctionFunction

NGC205

M33

Baumgardt et al. (2003)

How Low Can You Go?How Low Can You Go? 102 to 104 M BH have long been suspected to form at the center of dense stellar clusters (e.g. Wyller

1970; Bahcall & Ostriker 1975; Frank & Rees 1976; Lightman & Shapiro 1977; Marchant & Shapiro 1980; Quinlan & Shapiro 1987; Portegies Zwart et al. 1999; Ebisuzaki et al. 2001..)

M15 Gerssen et al. (2002): < a few thousand

M Baumgardt et al. (2003): increase in the

central M/L explained by a cluster of neutron stars and/or white dwarf.

McNamara et al. (2003): “little evidence that M15 possesses an IMBH” based on proper motion study

See poster by Dalia Chakrabarty

G1 (Gebhardt et al. (2002): M(BH) ~ 20,000

M (1.5 level) based on integrated stellar kinematics

Baumgardt et al. (2003) “there seems to be no need to invoke the presence of an IMBH in G1” based on N-body simulations

Off-nuclear ULXs (e.g. Miller & Colbert 2003): fluxes in excess of the angle-averaged flux Eddington luminosity of a 20 M BH, many associated with star clusters

Gebhardt et al. (2002)

Gerssen et al. (2002)

The High Mass End of the SBH Mass The High Mass End of the SBH Mass FunctionFunction

Richstone et al., cycle 9, 50 orbits, stellar dynamics NGC1399, NGC1961, NGC4061, NGC4649

Ferrarese & Miralda Escudé, cycle12, 29 orbits, gas dynamics BCGs in A2052, A2593, A1836, A3565

Richstone et al., cycle13, ?? orbits, stellar dynamics NGC2832, IC1695, NGC4472, ESO507-G045, NGC7619, NGC4486, NGC1316

Systematics: Building the Local Systematics: Building the Local SampleSample

HST

30m

8m

CfA Redshift Sample, (Huchra et al. 1990)

Fo

rna

x

Vir

go

M10

1 g

rou

p

ConclusionsConclusions HST’s two main contributions to this field, both of which have been made possible by its high

spatial resolution, are:

the discovery of small (~ 1 arcsec), regular dust/gas disks, has opened a new possibility of constraining the central potential.

the measurement of SBH masses in a statistically significant number of galaxies, by resolving the sphere of influence

The M relation must reflect (perhaps indirectly) the fundamental mode by which SBH form and evolve. A connection between SBHs and dark matter halos is certainly present. Establishing whether the relation is fundamental entail measuring dark matter halo masses in large sample of galaxies, which is best done using ground based telescopes.

Future progress hinges on being able to obtain accurate (10%) and reliable, mass determinations in diverse environments. In the optical, this requires the use of Integral Field Units coupled with high spatial resolution data.

HST capabilities in exploring the low and high mass end of the SBH mass function are limited. Reverberation mapping might be the most promising method for this aim.

The cosmic evolution of the SBH mass function must be studies using reverberation mapping or secondary mass estimators based on reverberation mapping.