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Black Hole Demographics: Observations, Theory and Extrapolation to Intermediate-Mass

Black Hole Demographics: Observations, Theory and Extrapolation to Intermediate-Mass. Active Galaxies. Some galaxies show active phenomena in their centers: radio emission X-rays / gamma-rays Jets of material Superluminal motion Broad emission lines …

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Black Hole Demographics: Observations, Theory and Extrapolation to Intermediate-Mass

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  1. Black Hole Demographics: Observations, Theory and Extrapolation to Intermediate-Mass

  2. Active Galaxies • Some galaxies show active phenomena in their centers: • radio emission • X-rays / gamma-rays • Jets of material • Superluminal motion • Broad emission lines • … Supermassiveblack holes (BHs)(106-109 M) [M87] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  3. Quiescent Galaxies • Quasar and Active Galaxy Population Statistics as function of redshift  many normal galaxies were active in the past BHs common in quiescent galaxies [Fan et al. 2001] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  4. BH Detections and Mass Measurements • A BH reveals itself through the gravitational pull it exerts on surrounding material. • Close to a black hole material will move rapidly • Kepler: V2~ GM/r • Detection: Massive Dark Object (MDO) • If an MDO can be demonstrated to be very small  density must be enormousassumed to be a BH Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  5. Dynamical Tracers andComplications • Stars: • Pro: Available in all galaxies; motions completely gravitational. Hubble SpaceTelescope Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  6. The Milky Way Galaxy Center • Near-infrared images show proper motions of stars that move rapidly around a central black hole (Sgr A*) with MBH =3x 106M [Ghez et al.] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  7. Dynamical Interpretation of Stellar Motions • Stars: • Con: Interpretation often complicated, because generally only projected motions are observed, and the 3D orbital structure is unknown • Various codes exist to do thenecessary modeling, but discussion continue about interpretation anderror analysis Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  8. Dynamical Tracers andComplications • Gas: • Pro: Rapid gas motions observed in many AGN (narrow-line regions and broad-line regions). • Con: Interpretation often complicated, because hydrodynamical forces, outflow, inflow, etc. may be as important as gravity. [M84] [Bower, Green, et al.] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  9. BH Masses From Gas Kinematics • Rotating nuclear gas disks in (active) galaxy centers: [NGC 4258] [NGC 7052] Water maser disks (VLBI) Optical emission-line gas disks Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  10. BH Masses From Gas Kinematics [Welsh et al.] [Reynolds] BLR reverberation mapping X-ray iron K emission lines Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  11. Black Hole Demographics • BH mass relation to • galaxy properties? (do all galaxies have BHs?) • galaxy activity and quasar statistics? • galaxy formation and galaxy interactions? Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  12. Back-of-the-Envelope Demographics • Insights from some well-studied galaxies: Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  13. Back-of-the-Envelope Demographics • Faber-Jackson : Lbul 3.5 • Fundamental Plane : Mbul/Lbul  Lbul0.2Mbul 4.2 • BH Demographics: MBH  Mbul MBH 4.2 Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  14. MBH -  relation • ~30 trustworthy MBH determinations • Good correlation with  • Scatter ~0.3 dex • Slope = 4.0 ± 0.3 (but lots of discussion about the exact value; Gebhardt et al., Ferrarese & Merritt, etc.) [Tremaine et al., 2002] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  15. MBH – Mbul relation • Long history, e.g., • Kormendy & Richstone (1995) • Magorrian et al. (1998) • Recent work • Marconi & Hunt (2003) • Haring & Rix (2004) • Scatter ~0.3 dex • similar as MBH -  relation! • Slope = 1.0 ± 0.1 • Correlation with Lbul not much worse … [Marconi & Hunt 2003] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  16. MBH – MDM relation • Demographics : MBH 4.0 • Bulges :   Vcirc1.2 • Assume : Vcirc ~ Vvir • Cosmology : MDM  Vcirc3  MBH MDM1.6 [Ferrarese 2002] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  17. MBH – concentration relation • MBH also correlates with a measure of galaxy light concentration (Graham et al. 2001) • Scatter ~0.3 dex • alsosimilar asMBH -  relation … Concentration [Graham et al. 2001] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  18. Comparison of BH Demographics Relations • What fundamentally drives MBH? • At present there is little reason to consider any of the relations more “fundamental” than the others • Important for extrapolations, e.g, • MBH driven by  : globular clusters could have IMBHs • MBH driven by MDM : globular clusters may not have IMBHs • MBH -  is popular because •  is a directly observed quantity (and emission line width can be used as a proxy) •  can be theoretically related to dark halo properties (Mgal, Lgal, and light concentration relate to baryons) Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  19. Evolution of theMBH -  relation for AGNs • BLR:MBH ~ V2 R / G • V : line-width(BLR) • R : reverberation mapping photoionization modeling R  Lcont0.5 • NLR: FWHM[OIII] • Shields et al. (2003): no sign of evolution with redshift (z < 3) Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  20. The Link between Nearby Galaxies and Distant AGN • Integral over MBH -  relation Local BHs:  ~ 3  105M Mpc-3 • Energy density in QSO radiation + assumed accretion efficiency ~0.1 Integrated luminous QSO accretion:  ~ 2  105M Mpc-3 • X-ray background + corrections Integrated obscured accretion:  ~ 2  105M Mpc-3 • All BHs (more-or-less) accounted for …. Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  21. The Questions of BH Formation • How is a BH formed initially? • A small seed BH is formed originally • From Population III evolution[Madau & Rees; Volonteri et al.; Schneider et al; Islam et al.] • From Evolution of a dense star cluster[Quinlan & Shapiro; Lee; Portegies Zwart & McMillan; Baumgarth et al; Gurkan et al] • A massive BH is formed by direct collapse of a gas cloud • H2 cooling must be suppressed[Bromm & Loeb] Rees (1984) Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  22. The Questions of BH Formation • When is a BH formed initially? • Before galaxy/bulge formation • During galaxy/bulge formation[Adams et al.] • After galaxy/bulge formation • When do BHs gain their mass? • Early on • Intermittent over time (e.g., during mergers) • Slowly over time (e.g., adiabatic growth) Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  23. The Questions of BH Formation • What do BHs accrete to grow in mass? • Gas [Kauffmann & Haehnelt; Di Matteo et al; Bromley et al] • Stars [Zhao et al.] • BHs [Volonteri et al.; Schneider et al; Islam et al.; Hughes & Blandford] • Dark Matter [Ostriker] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  24. The Questions of BH Formation • How does galaxy merging affect the BHs? • Trigger accretion/activity [Kauffmann & Haehnelt; Di Matteo et al; Bromley et al] • Changes both galaxy and BH properties • Merging timescale • Slingshot ejection • Gravitational Wave Recoil [Madau & Quataert] [NGC 6240] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  25. The Questions of BH Formation • What mechanism regulates BH mass/growth? • Availability of material to accrete • Feedback/Self-Regulation • Competition between star formation and BH growth[Burkert & Silk] • Accretion limited by mechanical feedback[Silk & Rees; King] • Accretion limited by heating due to the BH[Ciotti & Ostriker] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  26. Comparison of Models to BH Demographics • Scaling arguments in many models give MBH k (k~4) • Cosmologically motivated (semi-analytical) models fit MBH 4 and many other observations, but require fine-tuning of ad-hoc assumptions • Our improved understanding of BH demographics hasn’t really reduced the number of plausible scenarios … [Haehnelt & Kauffmann 2000] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  27. Are there IMBHs in Galaxy Centers? • BHs detected so far in • Hot stellar systems • With  >70 km/s • Do all galaxies have BHs? • Do intermediate-mass BHs (IMBHs) exist in galaxy centers with  < 50 km/s? Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  28. Does Theory suggest a Minimum MBH ? • Most models make no definitive statement about this • Models that address this face difficulties for low-mass galaxies • Star formation and feedback critically important • High-redshift physics critical • Cosmological simulations lack resolution • If supermassive BH formation involves growth from seeds < 106M, it is easy to imagine that some BHs may not have had the opportunity to grow supermassive •  Observational study of late-type galaxies needed Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  29. Central Structure of Late Type Spiral Galaxies • Late-type galaxies(Sc-Sd) generally host a nuclear star cluster • HST imaging(Boeker et al) • in 75% of a large sample • Barely resolved (<0.1”) • VLT spectroscopy (Walcher et al) • Age ~ 108-9 years • M ~ 106M [Boeker et al. 2002] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  30. Central Structure of Dwarf Elliptical (dE) Galaxies • dEs brighter than MV = -16 generally host a nuclear star cluster (“nucleated”) • Keck spectroscopy(Geha et al) • Age ~ 5 Gyrs • M ~ 106M • dEs may have formed from harassment of late-type spirals Evolutionary Connection ? [NGC 205] [Cuillandre et al.] Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  31. Relation of Nuclear Clusters to Other Hot Stellar Systems • In Fundamental-Plane space, nuclear star clusters are most similar to Globular Clusters; they have similar size, but are more massive and denser ~I3 M/L M M Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  32. Black Hole constraints in Low Dispersion Systems • Some very late-type galaxies are active,e.g., NGC 4395 (Sm), POX52 (dE) • BH mass estimated at MBH ~ 105 M • Both galaxies have a nuclear star cluster • Questions: • How typical are these galaxies? • Did the BH form because of the galaxy potential well? or • Did the BH form because there is a cluster? and if so • Do such BHs also form/exist in isolated star clusters? Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  33. Stellar Kinematical BH studies in Late-Type Galaxies • Stellar kinematics: only MBH upper limits • Irregulars ?? Dwarf Spheroidals ?? • Dwarf Ellipticals (Geha, Guhathakurta & vdM) •  = 20-50 km/s; MBH < 107 M • Late-Type spirals (IC 342 Boeker, vdM & Vacca) •  = 33 km/s; MBH <105.7 M • Interesting BH limits/detections: • Requires spatial resolution of cluster • restricted to HST data for Local Group galaxies Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  34. Case Study: IC 342 •  = 33 km/s MBH <105.7 M(upper limit). Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  35. M33 • Nucleus/star cluster dominates central few arcsec • HST/STIS: • Gebhardt et al.,Merritt et al. •  = 24 km/s • MBH <1500-3000 M(upper limit) Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  36. IMBHs in Globular Clusters? • Studies of Globular Cluster kinematics are probing an interesting mass range • Controversial results/upper limits • G1 • M15 • Interestingly, consistent withMBH -  relation … Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

  37. Conclusions: • BH demographics well mapped for supermassive BHs • MBH  Mbul  4 can be explained by many scenarios • BH studies in late-type galaxies are emerging; IMBHs exist there but may not be ubiquitous • There may be a continuum in central structure from early-type galaxies to late-type galaxies to Globular Clusters Roeland van der Marel - Space Telescope Science Institute marel@stsci.edu http://www.stsci.edu/~marel

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