demography of supermassive black holes: mergers & gravitational waves

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Demography of supermassive black holes: mergers & gravitational waves. Françoise Combes Observatoire de Paris. Monday 9 November. Overview. 1- Co-evolution of galaxies and Black holes 2-Feedback effects? 3- Quasars at z~6 4- MBH growth 5-Steps in the BH merging - PowerPoint PPT Presentation

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  • Demography of supermassive black holes: mergers & gravitational wavesFranoise CombesObservatoire de ParisMonday 9 November

  • Overview1- Co-evolution of galaxies and Black holes2-Feedback effects?3- Quasars at z~64- MBH growth5-Steps in the BH merging6- Observing binary black holes7- LISA

  • Ubiquity of Massive holes in galaxiesThe most massive BHBlack hole mass scales with bulge mass not total massSome BH at least MaybeGiant Ellipticals/S0s SpiralsDwarfsGlobularClusters

  • 3C31: radio quasars are rare

  • Scaling SMBH, M-s relationBlue: stellar velocities Green: gas velocitiesRed: disks with masers H2O, OH..(Magorrian et al 98, Gebhardt et al 02, Ferrarese &Merritt 01,Tremaine et al 02, Shields et al 02)Mbh = 0.2% Mbulge

  • Invoked mechanismsCo-evolution: each time gas is driven to the center to form stars, a fraction fuels the BHPossible, but through secular evolution/pseudo-bulges & interactions

    Delayed co-evolution: Different time-scalesBetter, since it is difficult to find good correlations of AGN and bars, or with interactions

    Self-regulated growthFeedback mechanisms: related to the potential well (bulge mass)

  • Co-evolution BH and galaxiesPLE: Pure Luminosity EvolutionLDDE Luminosity-dependent Density EvolutionRatio 1000since massloss 50%

  • BHAR and SFR versus z--SFR__BHARDotted lines are BHAR shifted by 100 in Number and 20 in Rate

  • BHAR and SFR split for intensityTotal is dominated by low-intensitiesz=1Zheng et al 2009

  • BHA and SF not in the same objectsfbulge-bh = 650, frecycle=2 1300z=1Zheng et al 2009

  • Hierarchical formation of BCGdry mergers since z=150% of stars formed at z=5; mass assembling after z=0.5De Lucia & Blaizot 2007

  • Overview1- Co-evolution of galaxies and Black holes2-Feedback effects?3- Quasars at z~64- MBH growth5-Steps in the BH merging6- Observing binary black holes7- LISA

  • Feedback due to Starburst or AGNDi Matteo et al 2005

  • Perseus Clusterexample of AGN feedbackSalom et al 2006Fabian et al 2003

  • Overview1- Co-evolution of galaxies and Black holes2-Feedback effects?3- Quasars at z~64- MBH growth5-Steps in the BH merging6- Observing binary black holes7- LISA

  • The most distant QSO at z=6.4Beam 0.3" PdB Age ~ 1 GyrKeck z-bandDjorgovski et alFan et al 2003, White et al 2003Mdust ~108Mo (Bertoldi et al 2003)MBH = 1.5 109Mo (Willot et al 2003)No HCN detectedCII, Walter et al 20091kpc scale starburst, 1000Mo/yr/kpc2CII

  • A very early assembly epoch for QSOs The highest redshift quasar currently knownSDSS 1148+3251 at z=6.4 has estimates of the SMBH mass MBH=2-6 x109 Msun (Willott et al 2003, Barth et al 2003)

    As massive as the largest SMBHs today, but when the Universe was

  • THE HIGHEST-REDSHIFT QUASARS Becker et al. (2000)How do they get a massMbh ~4 109 Mo ?

    Seed mass ~4 Mo

    20 e-folding times

    At Eddington luminositye-folding time40 (e/0.1) Myr

    Age of the universe at z=6Is 800 Myrs

  • Fluctuation generatorFluctuation amplifier(Graphics from Gary Hinshaw/WMAP team)Hot Dense SmoothCool Rarefied ClumpyBrief History of the Universe

  • BARYONS: need to COOL First action happens in the smallest halos with deep enough potential wells to allow this (at z~20-30) Hierarchical Galaxy Formation: small scales collapse firstand merge later to form more massive systems courtesy of M. KuhlenFirst seed black holes?

  • Overview1- Co-evolution of galaxies and Black holes2-Feedback effects?3- Quasars at z~64- MBH growth5-Steps in the BH merging6- Observing binary black holes7- LISA

  • Quasar hostDark matterGalaxiesMh= 5 x 1012M Mh= 51012M M*= 1011MSFR = 235 M /yr MBH= 108M

  • MBH GrowthCoalescence dominates dM/dt for z
  • BH growthFor simple dimensional relations, we can inferRacc = 0.3 M6/v22 pc and dM/dt is the Bondi accretion rate:dM/dt = 4 p R2 v r = (10-4 Mo/yr) M62/v23 r

    since dM/dt ~ M2, then the accretion time is ~ 1/M.for very low BH this takes much larger than the Hubble time.Therefore it requires a large seed, mergers of BH, or very largedensities, like in MW, 107 Mo/pc3

    Accretion-dominated growth, tg = tacc. Nice for Seyfert 1For QSO, they reach the Eddington limit, Ledd ~ M,the L ~ dM/dt ~ M2L/Ledd ~ M, the BH growth slows down when approching Ledd.tedd = M/(dM/dt)edd = 4.5 107 yr (0.1/e)equating tacc = tedd, this occurs for Mt = 2 108 Mo v23/r (e/0.1)

  • IMBH: do they exist?Some theories predict them

    Observational constraints: lensing, X-ray sources,galaxy centers, if the BBR extrapolate?

    Globular clusters (M15?, G1 in M31)

    AGN in dwarf galaxies: NGC 4395 (Filippenko & Ho 2003) MBH = likely 104-105 Mo (Seyf 1, no bulge)Low-ionisation, Lbol/LE = 210-2- 2 10-3problem of dwarfs: host nuclear star clusters of ~106 Mosolution: only in the Local Group, possible to separate

    In M33 < 103Mo, factor 10 below the BBR

  • Overview1- Co-evolution of galaxies and Black holes2-Feedback effects?3- Quasars at z~64- MBH growth5-Steps in the BH merging6- Observing binary black holes7- LISA

  • Merging steps for binary holes1. Dynamical friction2. Binary hardening due to starsor accretion of gas 3. Gravitational radiation t a4t aDo they merge?

  • Steps in a binary BH merger

  • DWARF GALAXIES/MINIHALOSELLIPTICAL GALAXIESmassVesc (km/s)1000100101091013Vrecoil (km/s) Gravitational rocketbinary center of mass recoil during coalescence due to asymmetric emission of GW (e.g. Fitchett 1983, Favata et al 2004, Blanchet et al 2005, Baker et al 2006)vrec 250 km/svesc from today galaxies vesc from high-z onesGR SIMULATIONS

  • at z >10 more than 80% of merging MBHs can be kicked out of their halo(Volonteri & Rees 2006)

    the gravitational rocket effect is a threat at the highest redshifts, when host halos are small and have shallow potential wells

    Can the merger process start early enough toAllow build-up of supermassive holes?

  • Evidence of recoil?Komossa et al 2008

    The ringdown radiationproduces anti-kickLe Tiec et al 2009Broad-line region dragged with the MBH

    2650 km/s difference with theNarrow-line region

  • a1a2a1a2a1a2Low kick velocities (~100 km s-1)High kick velocities (~1000 km s-1)Recoiling MBHs Volonteri 2009

  • Recoiling MBHRandom distribution of spin moduli

    Aligned or anti-aligned spinsspin-orbit isotropy

  • Overview1- Co-evolution of galaxies and Black holes2-Feedback effects?3- Quasars at z~64- MBH growth5-Steps in the BH merging6- Observing binary black holes7- LISA

  • Predicted Nb binary quasarsVolonteri et al 2009Not detected in the SDSShigh z, low M, and low LToday 2 out of 17500 detected

  • Are massive black holes rapidly spinning?Radio jets are observed preferentially in E-galaxiesDue to spin?

    Spin is modified by BH mergers and the coupling with the accretion disc

    mergers can spin BHs either up or down; alignment with the disc spins up

    In spiral galaxies, more random accretion, tidal disruption of stars, molecular cloud accretion

    BH Spin and host morphology

  • spin evolution by BH mergers onlyspin evolution by BH mergers AND accretionX-ray Fe Ka line

  • Mergers of SMBHMerging should take place rapidly enough, to avoid 3 BHand slingshot effect Milosavljevic & Merritt 2001Wandering simulations

  • 3C75, Owen et al 1985OJ287, light curve 100yrs Pietila 98Roos et al 1993VLBI maps of 1928+738 jetoscillations due to the orbital motions of the BH, period 3.2 yr

  • Overview1- Co-evolution of galaxies and Black holes2-Feedback effects?3- Quasars at z~64- MBH growth5-Steps in the BH merging6- Observing binary black holes7- LISA

  • LISAWill see mergersof 105 107 Msol black holes

  • Binary BH mergerCentrellaKip Thorne

  • Lisa sensitivity to massive black hole binaries