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07.04.04@KASI

07.04.04@KASI. Spin of Stellar Mass Black Holes: Key to Gamma-ray Bursts & Hypernovae. Chang-Hwan Lee @. Contents. Motivations. GRB. Hypernova. Spin of Stellar Mass Black Holes. before BH. before BH formation. at birth. at the time of BH formation. after BH. after BH formation. GRB.

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07.04.04@KASI

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  1. 07.04.04@KASI Spin of Stellar Mass Black Holes: Key to Gamma-ray Bursts & Hypernovae Chang-Hwan Lee @

  2. Contents Motivations GRB Hypernova Spin of Stellar Mass Black Holes before BH before BH formation at birth at the time of BH formation after BH after BH formation

  3. GRB Gamma-ray Bursts

  4. GRB Gamma-Ray Burst Duration: milli sec - min 1970s : Vela Satellite 1990s: CGRO, Beppo-SAX 2000s: HETE-II, Swift

  5. GRB

  6. GRB Galactic ?

  7. GRB

  8. GRB • 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 !

  9. GRB Two groups of GRBs • Short Hard Gamma-ray Bursts:Duration time < 2 secNS-NS, NS-LMBH mergers • Long-duration Gamma-ray Bursts:from spinning HMBH HMBH (High-mass black hole) 5-10 solar mass

  10. GRB Short-Hard Gamma-ray Burst : Colliding NS binaries Very Important for Gravitational Waves, too Science 308 (2005) 939

  11. GRB Long-duration GRBs: Afterglow Host Galaxy Association = Distance Estimation

  12. GRB GRB/Supernova Association GRB030329/Supernova Association (z=0.2: closest GRB/Afterglow) Top 10 Scientific Achievement in 2003 [New York Times] Nature 423 (2003), 843, 844, 847 Afterglow GRB980425 SN1998bw

  13. GRB What caused GRB/Supernova ? Most-likely Black Holes Callapsar: Asymmetric Explosion of a Massive Star Most-likely Rapid-Rotation

  14. GRB 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

  15. Hypernova Hypernovae

  16. Hypernova 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

  17. Hypernova Theoretical Black Holes ? Einstein’s General Relativity Sun : r = 3 km Earch : r = 9 mm Light cannot escape ! Total Nonsense !?

  18. Hypernova Observed (visible) Black Holes • Center of galaxies (106-109 Msun) • Intermediate Mass Black Holes (100-104 Msun) • Black Hole Binaries (Soft X-ray Transients )

  19. Hypernova Discovery of X-ray BH Binaries X-rays Mass accretion from a companion star to a compact object

  20. Hypernova Sources of Strong X-ray in the Universe X-ray emission by accretion • Neutron Stars [M < 3 MSun; R <15 km] • Black Holes • … …

  21. Hypernova Now we believe that black holes exist ! X-ray Observations (2002 Nobel Prize) • First Observation 1962 • First X-ray SatelliteUhuru (Dec. 1970) • .. • Current MissionsChandra (NASA) XMM-Newton (Europe) • Future Xeus (ESA), …… Chandra (NASA)

  22. Hypernova BH at the Center of a galaxy (M87) Jet=100000 light year

  23. Hypernova Number of X-ray Sources 1970s 1990s  1,000  50,000

  24. Hypernova 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 !

  25. Hypernova Soft X-ray Transients Black Hole Binaries in our Galaxy Galactic Disk XTE J1118+480

  26. Hypernova X-ray & Optical Telescopes Oscillating Brightness (GRO J1655-40)

  27. Hypernova m=2Msun ; MBH=6Msun Nova Sco 94 [Xi/H]: logarithmic abundances relative to solar Israelial et al. 1999, Nature It’s impossible for normal stars! Where did they come from?

  28. Hypernova Abundances in the secondary of Nova Sco They had to come from black hole progenitor when it exploded. Hypernova to explain the observations.

  29. Hypernova Another evidence ? C.M. System velocity (-106 km/s) : Abrupt Mass Loss by Explosion Mg,Si,S,…

  30. Hypernova Hypernova Explosions from Rotating BH Spinning BH (QPOs) High Black Hole Mass ( > 5 Msun) --- Maximum Neutron Star Mass < 2 Msun

  31. Hypernova Related Issues to be clarified • Neutrinos from hypernova • Nucleosynthesis from hypernova • Evidences of asymmetric explosions • Connection to GRBs • … …

  32. before BH at birth after BH Spin of Stellar Mass Black Holes

  33. Hypernovae in BH X-ray Binaries We have seen it twice. What about the other BH Binaries ? Nova Sco, V4641 Sgr

  34. Q) How can we understand the population of SXTs ? MS companion 15 10 MBH (Msun) Evolved companion 5 1 10 Orbital period (days)

  35. Progenitors • Evolution of BH Progenitor before BH Goal at birth after BH • Evolution of Donor Star Current Observation

  36. 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)

  37. before BH Mass of Iron CoreNS/BH mass

  38. before BH Fe core mass Neutron Star In Close Binaries

  39. before BH • In close binaries, only NS can be formed. • In order to from BH in binaries, the separation has to be far enough. • They have to meet after He core burning is finished • Later evolution doesn’t depend on the envelope. Red Giant H-shell burning Super GiantHe-shell burning Case A Case B Case C

  40. before BH Case C HMBH Case B NS/LMBH A

  41. before BH NS LMBH HMBH Formation in Case C HMBH Phase II Current 1915+105(108 Rsun)

  42. 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.

  43. at birth 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

  44. at birth Tidal interaction rapidlyspinning BH

  45. at birth Marginally bound orbit Kerr Black Holes Inner disk can extend to RSch for a=1 Marginally stable orbit

  46. at birth • Kerr parameter (Lee et al. 2002) Preexplosion orbital period (days)

  47. at birth BH Spin Observation Line Profile Doppler effect + Gravitational Redshifts Indication of BH spin

  48. at birth • Kerr parameter 4U 1543-47GRO J1655-40 Shafee et al. (2006) Preexplosion orbital period (days)

  49. at birth Reconstructed BH Binaries at Birth BH Spin – 10000/sec HN/GRB

  50. at birth What caused GRB/Supernova ? Most-likely Rapidly Spinning Black Holes Callapsar: Asymmetric Explosion of a Massive Star

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