spins of supermassive black holes in quasars and galaxies jian-min wang ( 王建民 ) institute of...
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Spins of supermassive black holes in quasars and galaxies
Jian-Min Wang (王建民 )Institute of High Energy Physics
Chinese Academy of Sciences, Beijing
Dec 1, 2009, ITP
SMBH properties
Physical BHs: mass, spin and charge
Astrophysical SMBHs• Growth: accretion and mergers• Spins: accretion manner, mergers• Formation: high redshift• Duty cycle: activity, coevolution• Obscuration: unification scheme
Outline
• Introduction: quasars and AGNs• Spins 1) Spins: measured from X-rays 2) Spins: measured from -rays 3) spins: cosmological evolution
• Dual AGNs: gravitation wave
• Conclusions • open questions
AGNs and Quasars: Introduction
• Observations: spectra and classifications• Morphology• Theoretical model
Spectral classification
Obscured AGNs by IR observatiosn
NGC 1068
Accretion disks: AGNs and Quasars
Coevolution of SMBH and galaxies
Measuring SMBH spins from X-rays
BH accretion disk• Release of Gravitational
energy
• Accretion rates hot corona ADAFs (advection-
dominated accretion flows)
• Geometry of Accretion
Measurements of SMBH spins from X-rays
• Spectral shape• Last stable orbit: radiative efficiency
a*: specific angular momentum
Spectral shape + last stable orbit→a*
Reflection of X-rays from cold disk
Line profiles:
affected by the Doppler shifts and gravity
Dependences of profiles on parameters(Fabian et al. 1989; Laor 1990)
• Model parameters: orientation θ emissivity R-β
spins: a*
• a*=0.998, β=0.5
On orientation
On spins
On β
ASCA observation of MCG 6-30-15(Tanaka, et al. 1995, Nature, 375, 659 )
XMM/Newton observations(Fabian et al. 2002, MNRAS, 335, L1)
Suzaku observations (Miniutti et al. 2007, PASJ, 59, S315)
2 Spins of SMBHs from -rays: in M87(Wang et al. 2008, ApJ, 676, L109; Li, Y. et al. 2009, ApJ, 699, 513 )
M87: MBH=3.2 ×109M⊙; D=16Mpc
M87
Conclusions:
1) t ≤ 2 days; 2) Non-beaming effects
GLAST/Fermi observations(Abado et al. 2009, ApJ, 707, 55)
e-rays escaping from the central region
28
e
65.0a
3 Spins: cosmological evolution
QSOgalaxy
QSO
QSOgalaxy
QSO
NN
N
tt
t
tgalaxy
tQSO
Wang et al. (2006;2008): duty cycle
Soltan (1982); Chokshi & Turner (1992); Yu & Tremaine (2002); Marconi et al. (2004): =0.1
Main growth of SMBH is driven by accretion
Understanding trigger of SMBHs: spins
Spin evolution: -equation(Wang, Hu et al. 2009, ApJ, 697, L141)
SDSSin relation ion reverberat :qso
Properties and advantages:
1) only depends on observables
2) deep survey data for δ: up to redshift z
3) no need to compare with local BH mass density
4) Spin evolution
Bolometric luminosity function and density(Hopkins et al. 2007)
Mass function and BH density(Vestergaard et al. 2008; 2009)
Results
Luminosity density
SMBH density
Vestergaard et al. (2009)
Duty cycle
Hopkins et al. (2007)
Cosmological evolution of SMBH spins
King & Pringle (2007;2008): random accretion
Random accretion: spin-down
MnMMn
ii
1
n
i
n
iii LnLLLL
1
2
1
22 ;
2/12/1
nM
Ln
M
La
Evidence for random accretion• Schmidt (1997), Pringle (1998) jet/disk is randomly-orientated torus is randomly-orientated disk+torus+galaxy have random orientation.
• Munoz Marin (2007)
Numerical simulations(Berti & Volonteri 2008)
Pure mergers Merger+standard accretion Merger+random accretion
What is driving the random accretion onto SMBH?
4 Dual AGNs: gravitational wave(Wang et al. 2009, ApJ, 705, L76)
SDSS: Sloan Digital Sky Survey
• 87 type 2 AGN sample
• Measurements: redshifts
• Properties?
Double peaked [O III] profile:
T. Heckman (1980; 1981)Whittle (1985)
Kepler Relation
Liu, Shen, Strauss et al. (2009, arXiv: 0908:2426)
Kepler relation
Merritt & Ekers (2002)
Conclusions
1) fast spins: in MCG -6-30-15 and M87
2) strong evolution of SMBH spins: spin-down
3) merging galaxies: dual AGNs
Open questions
• X-rays: more detailed and high energy solution• -rays: more observations• Spin evolution: co-evolution of SMBHs and
galaxies• Mergers: major and minor mergers.
Thanks for Attention