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Marianne Vestergaard University of Arizona

First Steps Toward Constraining Supermassive Black-Hole Growth: Mass Estimates of Black Holes in Distant Quasars. Marianne Vestergaard University of Arizona.

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Marianne Vestergaard University of Arizona

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  1. First Steps Toward Constraining Supermassive Black-Hole Growth:Mass Estimates of Black Holes in Distant Quasars Marianne Vestergaard University of Arizona Collaborators:Alex Beelen, Misty Bentz, Frank Bertoldi, Chris Carilli, Pierre Cox, Xiaohui Fan, Shai Kaspi, Dan Maoz, Hagai Netzer, Chris Onken, Pat Osmer, Chien Peng, Brad Peterson, Rick Pogge, Gordon Richards, Francesco Shankar, Adam Steed, Fabian Walter, David Weinberg Drexel University, February 10, 2006

  2. Active Galactic Nuclei • Bright galaxies with a point-source of non-stellar activity in nuclei • They are rare – comprise only a few percent of brightgalaxies • The most powerful are called quasars. • Quasar nuclei outshine their host galaxy light

  3. (Elvis et al. 1994) ~10 17 cm -- scale of our solar system (Francis et al. 1991)

  4. Supermassive Black Holes • How are their mass measured? • How do they grow? • How are black holes and galaxies connected?

  5. Black Holes and Galaxy Formation • Black holes are likely ubiquitous in galaxy centers • MBH – σ* relationship

  6. The M – σ Relationship M  σ4 (Tremaine et al. 2002; See also Ferrarese & Merritt 2000; Gebhardt et al. 2000) Black Hole Mass Bulge Velocity Dispersion

  7. Black Holes and Galaxy Formation • Black holes are likely ubiquitous in galaxy centers • MBH – σ* relationship • Formation and evolution of bulges and black holes must be intimately connected • When was it established? And how? • What came first, black hole or bulge (galaxy)? • Black hole/star-formation feedback (theory) • Negative feedback kills star formation and black hole growth by expelling gas (e.g., Springel, Di Matteo, & Hernquist 2005)

  8. Star formation activity Black hole activity Time (Gyr) (Springel et al. 2005)

  9. Black Holes and Galaxy Formation • Black holes are likely ubiquitous in galaxy centers • MBH – σ* relationship • Formation and evolution of bulges and black holes must be intimately connected • When was it established? And how? • What came first, black hole or bulge (galaxy)? • Black hole/star-formation feedback (theory) • Negative feedback kills star formation and black hole growth by expelling gas (e.g., Springel, Di Matteo, & Hernquist 2005) • Positive feedback stimulate star formation (Silk 2005) • Consequence: Galaxy bulges form later than supermassive black holes

  10. Talk Outline • Black Hole Mass • Determinations • Distributions • Black Hole – Galaxy Connection • Black Hole Evolution

  11. Talk Outline • Black Hole Mass • Determinations • Distributions • Black Hole – Galaxy Connection • Black Hole Evolution

  12. Black Hole Mass mv2 – GmMBH /R = 0 M m

  13. Black Hole Mass MBH = v2 R /G M

  14. Black Hole Mass MBH = v2 R /G

  15. Black Hole Mass R MBH = v2 R /G V Insert figure from HST/ MW?

  16. HST/STIS 109 108 8m telescope 30m telesc. Black Hole Mass (Ferrarese 2003) 10 100 Distance (Mpc) Why Study Quasar Black-Holes? • Quiescent black holes (in normal galaxies) can only be studied in the nearby Universe • Quasars are luminous and therefore ideal tracers of black holes to the highest observable redshifts • Their host galaxies are prime targets for studying galaxy evolution in the early Universe

  17. Stellar kinematics Gas kinematics Reverberation mapping (√) (√) √ √ How Can MBH be Determined for Active Black Holes? Local Universe Higher-z

  18. Mass estimates from the virial theorem: M = f (rV 2 /G) where r = scale length of region V=velocity dispersion f = a factor of order unity, depends on details of geometry and kinematics Possible Virial Estimators In units of the Schwarzschild radius RS = 2GM/c2 = 3 × 1013M8 cm. Note: the reverberation technique is independent of angular resolution

  19. Virial Mass Estimates MBH = f v2 RBLR/G Reverberation Mapping: RBLR= c τ t = t3 +  t = t2 t1 – t2 =  t = t3 t = t1

  20. Reverberation Mapping Results Continuum Light Curves Emission line NGC 5548, the most closely monitored active galaxy (Peterson et al. 2002)

  21. Virial Mass Estimates t = t2 MBH = f v2 RBLR/G Reverberation Mapping: • RBLR= c τ • vBLR Line width in variable (rms) spectrum t = t3 +  t1– t2=  t = t3 t = t1

  22. Reverberation Mapping NGC 5548, the most closely monitored active galaxy (Peterson et al. 1999)

  23. Velocity Dispersion of the Broad Line Region and the Virial Mass MBH = f v2 RBLR/G • Velocity dispersion is measured from the line in the rms spectrum. • The rms spectrum isolates the variable part of the lines. • Constant components (like narrow lines) vanish in rms spectrum f depends on structure and geometry of broad line region (based on Korista et al. 1995)

  24. MBH-: Comparison of Active and Quiescent Galaxies Mass • Reverberation masses appear to fall along the MBH -  relation for quiescent galaxies • The scatter is also similar: ≲ a factor of 3 Gals AGNs Bulge velocity dispersion (Courtesy C. Onken)

  25. Stellar kinematics Gas kinematics Reverberation mapping (√) (√) √ √ How Can Quasar MBH be Determined? Local Universe Higher-z • Scaling relations √ √

  26. Virial Mass Estimates MBH = f v2 RBLR/G • Reverberation Mapping: RBLR=cτ, vBLR Radius – Luminosity Relation:(Kaspi et al. (incl MV) 2005; Bentz,Peterson, Pogge,MV,Onken 2006, ApJ, submitted) • Scaling Relationships: MBH FWHM2 Lβ RBLR  Lλ(5100Å)0.50 RBLR  Lλ(1350Å)0.53 (see e.g. Vestergaard 2002)

  27. Single-Epoch Mass Estimates - CIV  • 1  scatter = factor 2.3 Log[ MBH (Reverberation)/ M ] (Vestergaard & Peterson 2006) Log [VP(CIV, single-epoch)/M]

  28. Virial Mass Estimates:MBH=f v2 RBLR/G Scaling Relationships: (calibrated to 2004 Reverberation MBH) • CIV: 1σ uncertainty: factor ~3.5 • Hβ:   ( Vestergaard & Peterson 2006) (see also Vestergaard 2002, and McLure & Jarvis 2002 for MgII)

  29. NGC 5548 Highest ionization lines have smallest lags and largest Doppler widths.  Filled circles: 1989 data from IUE and ground-based telescopes.  Open circles: 1993 data from HST and IUE. • Dotted line corresponds to virial relationship with M = 6 × 107 M. R (M/V) -1/2 Peterson and Wandel 1999

  30. Radius – Luminosity Relation (Data from Kaspi et al. 2005) (Dietrich et al 2002) Virial Relationships • All 4 testable AGNs comply: • NGC 7469: 1.2 107M • NGC 3783: 3.0 107M • NGC 5548: 6.7 107M • 3C 390.3: 2.9 108M • Scalings between lines: vFWHM2(H) lag (H) • vFWHM2(CIV) lag (CIV) • R-L relation extends to high-z and high luminosity quasars: • spectra similar(e.g., Dietrich et al 2002) • luminosities are not extreme • R-L defined for 1042 – 1046 erg/s(Vestergaard 2004) Emission lines: SiIV1400, CIV1549, HeII1640, CIII]1909, H4861, HeII4686 (Peterson & Wandel 1999, 2000; Onken & Peterson 2002)

  31. (Bentz, Peterson, Pogge, MV, Onken 2006) Improving the Scaling Relationships Main goal: improve scaling laws by reducing scatter R-L relation scatter dominates scatter in mass scaling law • Issues: • Host galaxy contamination • HST imaging • Accuracy of Single-epoch MBH estimates • HST & ground-based study (HST archive project, PI: MV) • Improved Masses and RBLR • Improved monitoring of nearby sources

  32. Talk Outline • Black Hole Mass • Determinations • Distributions • Black Hole – Galaxy Connection • Black Hole Evolution

  33. Masses of Distant Quasars • Ceilings at MBH≈1010 M LBOL< 1048 ergs/s • MBH ≈ 109 M beyond space density drop at z ≈ 3 (Vestergaard 2004) (H0=70 km/s/Mpc; ΩΛ = 0.7)

  34. Quasars • Dramatic space density drop at z ≳3 • Very luminous AGNs were much more common in the past. • The “quasar era” occurred when the Universe was 10-20% its current age. (Peterson 1997)

  35. Masses of Distant Quasars • Ceilings at MBH≈1010 M LBOL< 1048 ergs/s • MBH ≈ 109 M beyond space density drop at z ≈ 3 (Vestergaard et al. in prep) (H0=70 km/s/Mpc; ΩΛ = 0.7)

  36. Masses of Distant Quasars • Ceilings at MBH≈1010 M LBOL< 1048 ergs/s • MBH ≈ 109 M beyond space density drop at z ≈ 3 (Vestergaard et al. in prep) (DR3 Qcat: Schneider et al. 2005)

  37. Using MgII line to Estimate Black Hole Mass • Bridge 0.8 ≲ z ≲ 1.3 gap • Will use SDSS to calibrate MgII scaling law • Complications: • FeII contamination of line and continuum Requires template fitting (Vestergaard & Wilkes 2001)

  38. Talk Outline • Black Hole Masses • Black Hole – Galaxy Connection • Black Hole Evolution

  39. High Redshift Quasars and their Galaxies • UV, radio, X-ray properties similar at z > 3(e.g., Constantin et al. 2002; Dietrich et al. 2002; Stern et al. 2000; Mathur et al. 2002) • Black holes of distant quasars are very massive ~ (1-5)x 109M • Are their host galaxies also massive and old? • Circumstantial evidence for intense star formation on galaxy scales associated with quasars at z ≳ 4: • strong sub-mm/far-IR emission: ~108M warm dust • strong CO emission: ~1011M of cold molecular gas (Ohta et al. 1996; Walter et al. 2003)  Dust and CO emission: large scale star formation rates 500 – 2000 M/yr(e.g., Omont et al. 2001, Carilli et al. 2001)

  40. High Redshift Quasars and their Galaxies • Some evidence for massive, old galaxies: • z~2 quasar hosts have bulge luminosity consistent with old passively evolving stellar populations (Kukula et al. 2001) • Low-z host galaxies are dominated by old (8-14Gyr) stellar populations (Nolan et al. 2001)

  41. Redshift → (Data from Bruzual & Charlot 2003) (Vestergaard 2004) Quasar Host Galaxies at High Redshift • Conclusive test: mean age and mass of stellar bulge • Study of the most massive black holes at z ≳ 4 • HST UV imaging: young stars L(1500Å) → star formation rate • HST Cy15 IR imaging: older stars • Spitzer mid-IR: warm dust • Sub-mm data: cooler dust • CO imaging: cold molecular gas • Goals: • Characterize stellar bulge: mean age, mean mass, and star formation rate • Determine MBH /MBulge

  42. Black Hole to Bulge Mass Ratio at High Redshift (Peng et al. 2006, in prep)

  43. Lensed Quasar Host Galaxy at Redshift 4.7 Original data PSF+Galaxy Model Galaxy residual HST ACS UV image Strong sub-mm source VLA CO (2-1) emission image with Einstein Ring (Carilli et al. 2003)

  44. Talk Outline • Black Hole Masses • Black Hole – Galaxy Connection • Black Hole Evolution

  45. Predicted evolution of black hole mass functions for different growth scenarios (Steed & Weinberg 2003) Black Hole Growth in the Early Universe Theoretical model predictions: • Accretion only • Radiatively efficient • Radiatively inefficient • Merger activity • Obscured growth • A combination of the above?

  46. Preliminary Mass Functions of Active Supermassive Black Holes • Different samples show relatively consistent mass functions (shape, slope, normalization)(Vestergaard & Osmer, in prep.; Vestergaard, Fan, Osmer et al., in prep.) • Goal: constrain BH growth(with Fan, Osmer, Steeds, Shankar, Weinberg) • BQS: 10 700 sq. deg; B16.16mag • LBQS: 454 sq. deg; 16.0BJ18.85mag • SDSS: 182 sq. deg; i* 20mag • DR3: 5000 sq. deg.; i* >15, 19.1, 20.2 (H0=70 km/s/Mpc; ΩΛ = 0.7)

  47. Preliminary Mass Functions of Active Supermassive Black Holes • Different samples show relatively consistent mass functions (shape, slope)(Vestergaard & Osmer, in prep.; Vestergaard, Fan, Osmer et al., in prep.) • Goal: constrain BH growth(with Fan, Osmer, Steeds, Shankar, Weinberg) • BQS: 10 700 sq. deg; B16.16mag • LBQS: 454 sq. deg; 16.0BJ18.85mag • SDSS: 182 sq. deg; i* 20mag • DR3: 5000 sq. deg.; i* >15, 19.1, 20.2 (H0=70 km/s/Mpc; ΩΛ = 0.7)

  48. Preliminary Mass Functions of Active Supermassive Black Holes • Different samples show relatively consistent mass functions (shape, slope) (Vestergaard & Osmer, in prep.; Vestergaard, Fan, Osmer et al., in prep.) • Goal: constrain BH growth(with Fan, Osmer, Steeds, Shankar, Weinberg) • BQS: 10 700 sq. deg; B16.16mag • LBQS: 454 sq. deg; 16.0BJ18.85mag • SDSS: 182 sq. deg; i* 20mag • DR3: 5000 sq. deg.; i* >15, 19.1, 20.2 (H0=70 km/s/Mpc; ΩΛ = 0.7)

  49. Preliminary Mass Functions of Active Supermassive Black Holes • Locally mapped volume (R ≤ 100 Mpc): MBH≤ 3x109M • SDSS color-selected sample and DR3: (Fan et al. 2001, Schneider et al. 2005) ~9.5 quasars per Gpc3 with MBH≥ 5x109M → need ~25 times larger volume locally (R ≤ 290 Mpc) (H0=70 km/s/Mpc; ΩΛ = 0.7)

  50. Summary • >>>We can do physics with active galaxies and quasars<<< • MBH in Active Nuclei can be determined to within an accuracy: • Low-z: ~factor of 3 (measured) • Higher z: ~factor of 4 (estimated!!) • Black hole mass distributions: • <MBH>≈ 109 M, even at 4 ≲ z ≲ 6 • Maximum black hole mass at ~1010M • Black Hole Evolution and Galaxy Formation in Early Universe: • Ongoing study of galaxies at high redshift with the most massive black holes (~1010M) • MBH /MBulge ratio • Mass functions of active black holes • Constrain growth of black holes and their galaxy bulges by comparing these data with theoretical evolutionary models

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