Transcript Hypernovae
Hypernovae and Black Holes End of Life? or Beginning of New Life? 이창환 (서울대학교) Final Conclusion will be Believe or Not • 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 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? Einstein’s General Relativity Sun : r = 3 km Earch : r = 9 mm Light cannot escape ! Total Nonsense !? Soueces of Strong X-ray in the Universe Radiation from accreting material Theoretical Candidates • Neutron Stars [M < 3 MSun; R <15 km] • Black Holes •…… 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 Beyond Neutron Star We call it a Black Hole ! Black Hole Binaries in our Galaxy Galactic Disk XTE J1118+480 Explosions from black holes ? X-ray & Optical Telescopes Oscillating Brightness (GRO J1655-40) 15 Black Hole Binaries observed > 3000 active black hole binaries in our Galaxy 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? 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. [Hypernova=1031 Atomic Bomb at Hiroshima] Another evidence ? C.M. System velocity (-106 km/s) : Abrupt Mass Loss by Explosion Mg,Si,S,… Hypernova Explosions from Rotating BH Spinning BH (QPOs) High Black Hole Mass ( > 5 Msun) --- Maximum Neutron Star Mass < 3 Msun 동아일보 2002년 4월 24일 1. From where ? 태양의 1-2배 태양의 20-30배 질량 2. How to form ? 공전주기 < 12시간 외부 팽창, 내부 수축 Hypernovae 3. How to extract energy ? 블랙홀 자전 초당 1만번 Accretion Disk Rotating black hole is not so greedy! Falling material can survive! Supernovae Hypernovae New Life ! Hypernovae in BH X-ray Binaries We have seen it twice. So, it happens Everywhere ? Nova Sco, V4641 Sgr Hypernovae in BH X-ray Binaries Hypernovae ApJ 575 (2002) 996 Final Conclusion • We have seen 15 black hole binaries in our Galaxy. • We have seen evidences of hypernovae. Ironically, Black Holes are the sources of the most energetic explosions in the Universe after Big Bang If you believe, you will see the BHs ! Blessed are those who believe ! Why am I doing this ? It’s a lot of fun ! Thanks for your attendance !