Hypernovae and Black Holes

이창환 ( 서울대학교 )

End of Life? or

Beginning of New Life?

• We have seen 15 black hole binaries in our Galaxy.

• We have seen evidences of Hypernovae explosions in black hole binaries

• Ironically, Black Holes are the sources of the most energetic explosions in the Universe after Big Bang

Final Conclusion will be

Believe or Not

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 Seoul

What is Theoretical Black Hole?

Sun : r = 3 km

Earch : r = 9 mm

Total Nonsense !?

Einstein’s General Relativity

Light cannot escape !

Soueces of Strong X-ray in the Universe

• Neutron Stars [M < 3 MSun; R <15 km]

• Black Holes

• … …

Theoretical Candidates

Radiation from accreting material

Now Scientists believe that black hole exists !

X-ray Observations

•First Observation 1962

•First X-ray Satellite Uhuru (Dec. 1970)

•..

•Current Missions Chandra (NASA) XMM-Newton (Europe)

•Future Xeus (ESA), Constellation-X(NASA), etc

Chandra (NASA)

What is black hole in real observation ?• Strong souce of X-ray emission

• X-ray emission region is very small

• No stable star exists with given mass & size

We call it a Black Hole !

Beyond Neutron Star

Black Hole Binaries in our Galaxy

XTE J1118+480Galactic Disk

Explosions from black holes ?

Oscillating Brightness (GRO J1655-40)

X-ray & Optical Telescopes

15 Black Hole Binaries observed

> 3000 active

black hole binaries

in our Galaxy

Nova Sco 94

N O 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

m=2Msun ; MBH=6Msun

It’s impossible for normal stars!

Where did they come from?

Abundances in the secondary of Nova Sco

Hypernova to explain the observations.

[Hypernova=1031 Atomic Bomb at Hiroshima]

N O 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

They had to come from black hole progenitor when it exploded.

System velocity (-106 km/s) :

Abrupt Mass Loss by Explosion

Another evidence ?C.M.

Mg,Si,S,…

Hypernova Explosions from Rotating BH

Spinning BH (QPOs)

High Black Hole Mass ( > 5 Msun)

--- Maximum Neutron Star Mass < 3 Msun

1. From where ?

태양의 1-2 배

태양의 20-30 배 질량

2. How to form ?

외부 팽창 , 내부 수축

공전주기 < 12 시간

3. How to extract energy ?

블랙홀 자전 초당 1 만번

Hypernovae

Accretion Disk

Rotating black hole is not so greedy!

Falling material can survive!

New Life !

Supernovae Hypernovae

Hypernovae in BH X-ray Binaries

We have seen it twice.

So, it happens Everywhere ?

Nova Sco, V4641 Sgr

Hypernovae

Hypernovae in BH X-ray Binaries

ApJ, in press

동아일보 4 월 24 일

• We have seen 15 black hole binaries in our Galaxy.

• We have seen evidences of hypernovae.

Final Conclusion

If you believe, you will see the BHs !

Blessed are those who believe !

Ironically, Black Holes are the sources of the most energetic explosions in the Universe after Big Bang

Why am I doing this ?

It’s a lot of fun !

Thanks for your attendance !