galactic environment of nearby quiescent supermassive black holes

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Galactic Environment of Nearby Quiescent Supermassive Black Holes Q. Daniel Wang University of Massachusetts

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Galactic Environment of Nearby Quiescent Supermassive Black Holes. Q. Daniel Wang University of Massachusetts. SMBH and bulge mass correlation. SMBH and galaxy formation are closely related. Every galaxy probably contains a SMBH. Their masses are correlated. - PowerPoint PPT Presentation

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Page 1: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Galactic Environment of Nearby Quiescent Supermassive Black

Holes

Q. Daniel Wang

University of Massachusetts

Page 2: Galactic Environment of Nearby Quiescent Supermassive Black Holes

SMBH and galaxy formation are closely related

• Every galaxy probably contains a SMBH.

• Their masses are correlated.

• Physically, how this correlation is achieved is not clear.

• The SMBH growth is largely from gas accretion AGNs

SMBH and bulge mass correlation

Page 3: Galactic Environment of Nearby Quiescent Supermassive Black Holes

But most of SMBHs are not active in nearby galaxies. They are starved.

Why?

• Little gas falls into the galaxy center?

• Or the infalling gas is being removed, due to episodic AGN feedback or some continuous processes?

Answering these questions will help to understand the formation of SMBHs and galaxies in general.

Page 4: Galactic Environment of Nearby Quiescent Supermassive Black Holes

M31 (d=780 kpc)

IRAC 8 micro0.5-2 keV2-8 keV

Li & Wang 2007

Page 5: Galactic Environment of Nearby Quiescent Supermassive Black Holes

GALEX far-UV excess vs. Hα

Page 6: Galactic Environment of Nearby Quiescent Supermassive Black Holes

M31*: SMBH and its vicinity

• A red star cluster forming an elongated disk (Tremaine 1995)

• Mbh ~ 2 x 108 Msun (Bender et al. 2005)

• Apparent young (A-type) stars (t ~ 200 Myr) around the SMBH

• Alternatively, they may be post-HB stars formed from stripped redgiants and/or stellar mergers (e.g., Demargue & Virani 2007).

P3 (M31*)

P2

P1

Page 7: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Chandra/ACIS 0.5-8 keV vs. HST/ACS (F330W)

Chandra/ACIS limit on the X-ray luminosity of M31*

• Lx ~ 1(+-0.3)x1036 erg/s, consistent with the previous 3 upper limit from a Chandra/HRC (Garcia et al. 2005)

• kT ~ 0.3 keV• n ~ 0.1 cm-3

• Rb ~ 0.9”, Lb ~ 3x1040 erg/s

M31*P1

SSS

Page 8: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Chandra/ACIS source detection

With 1’ radius:

• Lx > 1036 erg/s: an enhanced number density dynamic formation

• 1036 > Lx > 1035: a deficit destruction of loosely bound LMXB?

Page 9: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Unresolved emission along the major-axis

Lx < 1035: : below the detection limit:

• CVs and active stars• hard (2-8 keV) emission

follows the near-IR light: a stellar origin

• soft (0.5-2 keV) emission only follows the near-IR light at large radii; excess in the inner bulge diffuse gas

0.5-1(2-8) keV; along major-axis

Page 10: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Diffuse soft X-ray emission

•stellar contribution subtracted•characteristics of hot gas in the bulge:

•z0 ~ 600 pc;

•T~ 0.3 keV;

•L0.5-2 keV ~ 31038 erg/s

IRAC 8 micro, K-band, 0.5-2 keV

Page 11: Galactic Environment of Nearby Quiescent Supermassive Black Holes

0.5-1(1-2) keV; along minor-axis

Diffuse emission along the minor axis

• X-ray shadows of spiral arms: extraplanar hot gas with a height > 2.5 kpc

Page 12: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Galactic bulge simulation• Parallel, adaptive mesh

refinement FLASH code• Finest refinement in one

octant down to 6 pc• Stellar mass injection

and SNe, following stellar light

• SN rate ~ 4x10-4 /yr• Mass injection rate ~0.1

Msun/yr)

10x10x10 kpc3 box

density distribution

Page 13: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Galactic Bulge Wind: Simulation

3x3x3 kpc3 box, density distribution

• Radiative cooling is not important in the bulge region, consistent with the observation

• Energy not dissipated locally

• Most of the energy is in the bulk motion and in waves

• The wind solution does depend on the outer boundary condition!

Page 14: Galactic Environment of Nearby Quiescent Supermassive Black Holes

0.5-2 keV diffuse X-ray vs. Spitzer MIPS 24 μm

Page 15: Galactic Environment of Nearby Quiescent Supermassive Black Holes

The Milky Way

Page 16: Galactic Environment of Nearby Quiescent Supermassive Black Holes

~ 1055 erg, or > 104

SNe is needed over the past 2 x 107 years!

Page 17: Galactic Environment of Nearby Quiescent Supermassive Black Holes

ROSAT Survey (1.5-keV Band)

Page 18: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Chandra survey of the Galactic center

Wang et al. (2002)

Page 19: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Massive star forming region: Composite Chandra map

Arches

Quintuplet GC

Chandra Intensity:

•1-4 keV

•4-6 keV

•4-9 keV

Wang, Hui, & Lang (2006)

Page 20: Galactic Environment of Nearby Quiescent Supermassive Black Holes

X-ray Flare from Sgr A*

Baganoff et al. (2003)

•Peak L(2-10 keV) 1035 erg s-1

•Lasted for about 3 hrs•Variability ~ a few minutesBut the observed Lx is ~10-4 of the expected!

Page 21: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Diffuse X-ray Spectrum

Decomposed into three components:

• CVs with T ~ 108 K• Hot gas with T ~

107K• Nonthermal: inverse

Compton scattering, bremstrahlung, and reflection

Hui & Wang 2008

Page 22: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Imaging decomposition

CV Hot gas

nonthermal

absorption

Page 23: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Hot gas vs. radio continuum

Page 24: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Comparison with other extended X-ray-emitting features

Sgr A*

IRS 13

PWN

Diffuse

The spectra of Sgr A*, IRS 13, and diffuse X-ray emission all show the Fe K line at ~6.6 keV NEI emission from gas heated recently (net~103 cm-3 yr).

Page 25: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Ongoing: 1) Deep Chandra Survey, 2) HST/NICMOS mapping of NIR continuum and Paschen- line emission (32’x13’, 144 orbits)

Great Observatory mapping of the GC

VLA 20cm Spitzer 8 m 1-9 keV

VLA 20cmSpitzer 8mSpitzer 3.6m

Page 26: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Conclusions• Cool gas is expected to fall into nuclear regions

of disk galaxies.• The gas can be heated, however, responsible for

excess of far-UV and Halpha emission as well as mass-loading to hot gas

• The heating may be due to steepening ofSN waves.

• The mass-loaded gas can produce subsonic outflows, consistent with X-ray observations:– moderate luminosity– low temperature– broad spatial distribution.

• Stellar energy feedback in galactic bulges may lead to the starvation of SMBHs!

Page 27: Galactic Environment of Nearby Quiescent Supermassive Black Holes

T ≤107 K

Filling factor?

Composition?

Physical properties?

Heating and cooling?

Mass loading?

CMZ

Page 28: Galactic Environment of Nearby Quiescent Supermassive Black Holes

Magnetic loopsCorona

Galactic disk