Spins of supermassive black holes in quasars and galaxies

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

NGC 5548 (AGN) versus NGC 3277 (Normal)

Accretion disks: AGNs and Quasars

Coevolution of SMBH and galaxies

Quasar evolution

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 momentumSpectral 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

NNN

ttt

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

nML

nMLa

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