black hole chaos the environments of the most super- massive black holes in the universe belinda...
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Black Hole Chaos
The Environments of the most super-massive black holes in the
UniverseBelinda Wilkes, Chandra X-ray Center, CfA
Francesca Civano, CfA
Black Hole
Matter spiraling inwards → accretion disk
• Nothing beats gravity → collapses forever• Light cannot escape from inside the event horizon
Stellar Mass Black Hole• Big, old star blows up
• Can be seen when in binary star systems
• BH pulls matter from companion star
• Bright, variable/bursting sources
BH and accretion disk
Star Jet
Black Hole: Mass and Spin
• Properties determine their effects on their surroundings• Spinning BH has a smaller “size” (event horizon is closer in)
No spin With spin
Super-massive Black Hole (SMBH) Galaxy-sized!
• Formed in centers of galaxies in early Universe
• 1 million – 1 billion times Sun’s mass
• SMBH size ~ our solar system (15 lt mins)
• SMBH grows as material falls in
Central Regions: Accretion Disk spinning around
SMBH• Matter spirals in to galactic
center and forms an accretion disk (~few lt.yrs.)
• Becomes very hot and outshines the 10 billion stars in the host galaxy → Quasar
• Hottest near center • X-rays good clear view, even
when edge-on• BH grows as matter falls in• Other matter is pushed
outwards: jets, winds
Artist’s Impressions!
But this one is real: Cen A
Model of Polar Jets
Proga et al. 2003
Accretion with latitude-dependent angular momentum and radial magnetic field can launch and sustain a jet
Radio Jets
• Electrons spiral around magnetic field at velocities close to light
• Emit radio-X-rays “non-thermal” emission
radio
Chandra X-ray Observatory
NASA’s X-ray Eye on the Universe
Launched in 1999
Actual Chandra First Light• Point source to focus
telescope• PKS0637-75, quasar at large
distance (z=0.5, 3 Gpc)• Shadow on side!• Known to have radio jet• X-ray Jet visible: 5” long,
200,000 lyrs
X-ray/Radio Jets in Quasars: M87 Galaxy
M87 jet in X-ray, radio and optical
More jets!
Cygnus A radio
3C273 X-ray
MS0735.6Radio/X-ray
Accretion Disk Winds
• Wind blown off surface of accretion disk
• Accelerated by radiation pressure
• High velocity gas observed
Proga et al. 2000AD surface
X-ray source
How do SMBHs form and grow?
• Secular: accreting from within the galaxy• Group: accretes from within the group of galaxies• Cosmological: accretes from cold dark matter filaments• Major Mergers:
Hopkins et al (2008)