Transcript Most-likely Black Holes

07.02.27@apctp
Spin of Stellar Mass Black Holes:
Hypernova and BH Spin Correlation in Soft X-ray BH Binaries
Chang-Hwan Lee @
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Compact Stars
• White Dwarf [M < 1.4 Msun; R=1000 km]
• Neutron Star [M < 3 Msun; R < 15 km]
• Black Holes
Density of Neutron Star
1 cm3
All buildings in Busan
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Theoretical Black Holes ?
Einstein’s General Relativity
Sun : r = 3 km
Earch : r = 9 mm
Light cannot escape !
Total Nonsense !?
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Observed (visible) Black Holes
 Center of galaxies [106-109 Msun]
 Black Hole Binaries
(Soft X-ray Transients )
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Discovery of blackhole binaries
Discovery of X-ray Binaries
X-rays
Mass accretion from a companion star to a compact object
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Sources of Strong X-ray in the Universe
X-ray emission by accretion
• Neutron Stars [M < 3 MSun; R <15 km]
• Black Holes
•……
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Now we believe that black holes exist !
X-ray Observations (2002 Nobel Prize)
•First Observation 1962
•First X-ray Satellite
Uhuru (Dec. 1970)
Chandra (NASA)
•..
•Current Missions
Chandra (NASA)
XMM-Newton (Europe)
•Future
Xeus (ESA), ……
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BH at the Center of a galaxy (M87)
Jet=100000 light year
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Number of X-ray Sources
1970s
 1,000
1990s
 50,000
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What is a black hole in real observation ?
• Souce
of strong X-ray emission
• X-ray emission region is very small
• No stable star exists with given mass & size
5-10 Msun
Beyond Neutron Star
We call it a Black Hole !
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Soft X-ray Transients
Black Hole Binaries in our Galaxy
Galactic Disk
XTE J1118+480
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X-ray & Optical Telescopes
Oscillating Brightness (GRO J1655-40)
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m=2Msun ; MBH=6Msun
N
O
Nova Sco 94
Mg
Si
S
Ti
Fe
[Xi/H]
0.45 1.00 0.90
0.90 0.75 0.90 0.10
error
0.50 0.30 0.40
0.30 0.20 0.40 0.20
[Xi/H]: logarithmic abundances relative to solar
Israelial et al. 1999, Nature
It’s impossible for normal stars!
Where did they come from?
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Abundances in the secondary of Nova Sco
N
[Xi/H]
O
Mg
0.45 1.00 0.90
Si
S
Ti
Fe
0.90 0.75 0.90 0.10
They had to come from black hole progenitor
error
0.50 0.30 0.40 0.30 0.20 0.40 0.20
when it exploded.
Hypernova to explain the observations.
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Another evidence ?
System velocity (-106 km/s) :
C.M.
Abrupt Mass Loss by Explosion
Mg,Si,S,…
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Hypernova Explosions from Rotating BH
Spinning BH (QPOs)
High Black Hole Mass ( > 5 Msun)
--- Maximum Neutron Star Mass < 2 Msun
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Related Issues to be clarified
•
Neutrinos from hypernova
•
Nucleosynthesis from hypernova
•
Evidences of asymmetric explosions
•
Connection to GRBs
•
……
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Hypernovae in BH X-ray Binaries
We have seen it twice.
So, does it happen everywhere ?
Nova Sco, V4641 Sgr
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Q) How can we understand the population of SXTs ?
MS companion
MBH (Msun)
15
10
5
Evolved companion
1
10
Orbital period (days)
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Progenitors
 Evolution of BH Progenitor
 before BH
Goal :
At the time BH Formation
 after BH
 Evolution of Donor Star
Current Observation
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before BH
High Mass Black Hole progenitor (20-40 Msolar)
 Bigger star evolves fast !
 High Mass Black Hole is formed when the separation is
large (Case C; meet at supergiant stage)
 NS/LMBH is formed when the separation is relatively
small (Case A, B; meet at/before red giant stage)
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before BH
Fe core mass
Neutron
Star
In Close Binaries
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before BH
Case C
Case B
HMBH
NS/LMBH
A
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before BH
HMBH Formation in Case C
NS
LMBH
HMBH
Phase II
Current
1915+105
(108 Rsun)
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before BH
Formation of Stellar Mass Black Holes
Assumption
 Case C Mass Transfer (in supergiant stage of BH
progenitor)
 If BH formation through Case B (in giant stage) is
possible, contrary to the observation, we should
see about 10 times more BHs in our Galaxy.
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At the time of BH Formation
Rapidly Rotating Black Holes
 Assumption: Synchronization of BH-Progenitor
Spin & Binary Orbital Period
 Rapidly rotating BH with large Kerr parameter
(even close to 1)
 SXTs with short orbital periods 
Possible sources of Hypernovae/GRB
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Marginally bound orbit
Kerr Black Holes
Inner disk can extend
to RSch for a=1
Marginally stable orbit
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At the time of BH Formation
 Kerr parameter (Lee et al. 2002)
Preexplosion orbital period (days)
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BH Spin Observation
Line Profile
Doppler effect +
Gravitational Redshifts
Indication of
BH spin
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At the time of BH Formation
 Kerr parameter
4U 1543-47
GRO J1655-40
Shafee et al. (2006)
Preexplosion orbital period (days)
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At the time BH Formation
Reconstructed BH Binaries at Birth
BH Spin – 10000/sec
HN/GRB
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At the time BH Formation
Gamma Ray Bursts from Black Hole Systems
• Energy > 1051 ergs
Most likely BHs !
• Rinit = O(100 km)
• M < 30 Msun
• dT = ms – min
•……
BH Binary is natural source of
rapidly rotating black hole
Energy in Hypernovae = Energy in GRBs
BH Binaries -> Long-duration GRBs (> 2 sec)
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after BH
Shrink
MS companion
I: Hubble Time
II: Main Sequence
III: Oveflow at t=0
Evolved Companion
Expand
AML: Angular Mom Loss
Nu: Nuclear Burning33
after BH
Current
Observation
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after BH
OK
?
15 Msun
10 Msun
Q) How to Evolve ?
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after BH
 Kerr parameter
4U 1543-47
GRO J1655-40
McClintock et al. (2006)
GRS 1915+105
P=33 days
a* > 0.98
Preexplosion orbital period (days)
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after BH
Q) How to form BHs in 10-15 Msun ?
 problem 1:
It’s hard to form BH with masses > 10 Msun from
stellar evolution.
 problem 2:
The current separation is too large.
 Problem 3:
Observed Kerr parameter is too big.
 easiest solution:
Accrete extra mass after BH formation
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after BH
?
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after BH
Conservative Mass Transfer
V4641 Sgr
Data: 33.5 days
GRS 1915+105
2.817 days
Consistent within error range
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after BH
1915+105
V4641 Sgr
15 Msun
9.5 Msun + 6.5 Msun
10 Msun
P=3 day
14 Msun + 2 Msun
P=33 days
Beauty of Simple Physical Laws !
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after BH
Spin-up due to accretion
GRS 1915+105
a* > 0.98
McClintock et al. (2006)
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after BH
 Kerr parameter
GRS 1915+105
P=33 days
a* > 0.98
4U 1543-47
GRO J1655-40
Preexplosion orbital period (days)
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At the time BH Formation
Pre-Explosion Properties
V4641 & 1915
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At the time BH Formation
Reconstructed BH Binaries at Birth
BH Spin – 10000/sec
HN/GRB
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Conclusions
•
Soft X-ray BH binaries

Formation and evolution :
- only “Case C mass transfer” can explain HMBH in binaries.

Spin of stellar-mass BHs :
- tidal (BH progenitor spin-orbit) interaction is consistent
with the current BH spin observation

Long-time scale GRBs and Hypernovae :
- Short orbital period ( P<0.5 day) HMBH binaries are the
sources of long-duration GRBs and Hypernovae
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Motivations
Gamma-Ray Burst
Duration: milli sec - min
1970s : Vela Satellite
1990s: CGRO, BeppoSAX
2000s: HETE-II, Swift
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Motivations
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Motivations
Galactic ?
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Motivations
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Motivations
 Gamma-Ray Bursts are the brightest events
in the Universe.
 During their peak, they emit more energy
than all the stars and galaxies in the
Universe combined !
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Motivations
Two groups of GRBs
 Short Hard Gamma-ray Bursts:
Duration time < 2 sec
NS-NS, NS-LMBH mergers
 Long-duration Gamma-ray Bursts:
from spinning HMBH
HMBH (High-mass black hole)
5-10 solar mass
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Motivations
Short-Hard Gamma-ray Burst : Colliding NS binaries
Very Important for
Gravitational Waves, too
Science 308 (2005) 939
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Motivations
Long-duration GRBs: Afterglow
Host Galaxy
Association
= Distance
Estimation
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Motivations
GRB/Supernova Association
GRB030329/Supernova Association
(z=0.2: closest GRB/Afterglow)
Top 10 Scientific Achievement in Afterglow
2003
[New York Times]
Nature 423 (2003), 843, 844, 847
GRB980425
SN1998bw
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Motivations
What caused GRB/Supernova ?
Most-likely
Black Holes
Callapsar: Asymmetric
Explosion of a Massive Star
Most-likely Rapid-Rotation
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Motivations
How to form rapidly spinning black holes?
Most likely in binaries (Soft X-ray Transients)
Companion star can keep the BH
progenitor rotating
Formation of rapidly rotating stellar mass BHs
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