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Supermassive Black Holes at High Redshifts. 王 建 民 高能物理研究所 粒子天体物理中心 July 4, 2005. Focus on: Supermassive BH after reionization stage. Outline. Black Holes at high- z: Formation Black Holes: mass, accretion rate and spin Obscured Black Holes by Hard X-ray & IR anti-hierachical growth
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Supermassive Black Holes at High Redshifts 王 建 民 高能物理研究所 粒子天体物理中心 July 4, 2005
Focus on: Supermassive BH after reionization stage
Outline • Black Holes at high-z: Formation • Black Holes: mass, accretion rate and spin • Obscured Black Holes by Hard X-ray & IR anti-hierachical growth • Summary: accretion or mergers
1. Formation at high-z • Implications of SMBHs 1.A Fundamental Relationship between Galaxies and Quasars Galaxies ← SMBHs → Quasars through SMBHs? Afterglows:are galaxies remnants of quasars? (Wang, J.-M. et al., 2005, ApJ, 625. L5) 2. MBH-MR/ Relation (Magorrian et al. 1995; Gebhardt et al. 2000) Coevolution?
BH Formation BH • Rees’ Diagram (1984) • Possible ways to form BHs • Evolutionary connection between Galaxy and Quasars • Metallicity and evolution? • (Wang, J.-M., 2001, A&A, 376, L39)
SMBH Formation at High-z • Question of SMBH formation 1) Angular momentum barrier 2) Fragmentation and star formation 3) a single SMBHs or a cluster of black holes? a cluster of black holes in the Galactic Center (Jordi & Gould astro-ph/0003269)
Black Hole Formation in High Redshift • Angular momentum induced by tidal torques Barness & Efstathious (1987) • Efficient Compton drag centralfugal barrier radius Rcb=J2/GM phase 1 (optically thin) and phase 2 (optically thick): Rcr 1) formation of BH via collapse: Rcr<Rcb 2) disk formation: Rcr>Rcb ionization is very important since bound-free section is generally smaller than Thomson’s z>100 Compton drag is efficient.
Numerical simulation of star cluster evolution processes:1) relaxation induced by 2-body gravitational encounters 2) tidal disruptions of stars by BH 3) stellar collisions 4) stellar evolution 5) BH growth Fokker-Planck equation (Newtonian or relativistic) early research:normal star cluster:Duncan & Shapiro (1983), Quinlan & Shapiro (1987, 1989)cluster of compact stars: Shapiro & Teukolsky (1985) Quinlan & Shapiro (1989) more recent: Freitag & Benz, 2001, A&A, 375, 711
Quasars and Galaxies • Era of Quasars Fueling SMBHs 1) fueling should be at 0.6 kpc 2) density 108M⊙/kpc3 such a condition just corresponds to the bulge! 3) plot of star formation rate and qso density Comparing with star formation rate and number density of QSOs, we learn that 1) SMBHs are formed before bulge. 2) SMBH grows via accretion after its formation 3) fueling is in shortage before maximum star formation.
Birth of Quasars/BH • Birth of Quasars: Q1205-30 (z = 3)Weidinger, Moller & Fynbo (2004, Nature, 430, 999) Haiman & Rees (2001): theoretical predictions Chicken-and-Egg Problem: Egg/black hole first !!! Challenge to Coevolution of Black Hole and Galaxies We still do not how to trigger the black hole
2.1 BH mass distribution(Vestergaard 2004, ApJ, 601, 676)Low redshift(<0.5): 87 BQS quasarsIntermediate redshift(1.5~3.5): 114 quasarsHigh redshift (>3.5): 150 quasars
2.2 BH Spins Volonteri et al. (2005, ApJ, 620, 69): Born with a=0.6 Pure merger merger+accretion
2.3 Black Hole Growth: FeedbackMcNamara et al. (2005, Nature, 433, 47), Chandra observation MS 0735.6+7421 PdV = 6*1061erg PdV =MBH c2 -> MBH ~3*108M⊙
Simulation and Obs. Barth et al., 2005, ApJ, 619,L151
3 Obscured black holes • Hard X-ray observations (Fabian 1999): A larger number of obscured AGNs
Fan, X. et al, 2005, AJ, 128, 515 Miyaji, et al., 2001, A&A • Radio, optical, soft X-ray luminosity function F
Ueda et al. (2003, ApJ, 598, 886) Hasinger (2004, astro-ph/0405667)Wang, J.-M., et al., (2005, ApJ, 627, L5)
Spitzer ObservationsMartinez-Sansigre et al. (2005, Nature, in press, astro-ph/0505486) Spitzer > 100 IRAS Spitzer >10 ISO ~80% AGNs are obscured
SMGs: Rapid growth(Alexander et al., 2005, Nature, 434, 738) • Submillimeter galaxies (SGMs): 1011M⊙ ultra-deep X-ray observation sample (2Ms Chandra Deep Field-North; CDF-N)
4. Summary • Open questions: 1) How to triger? Why is there fuel shortage? coevolution? (BH+bulge) 2) Black hole growth, spin, feedback? 3) Obscured black holes? • Future project: 1) James Webb ST 2) HXMT all sky survey