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ik10@icranet

ik10@icranet.org. Spin of Stellar Mass Black Holes: Key to Gamma-ray Bursts and Hypernovae. In collaboration with G.E. Brown, R.A.M.J. Wijers et al. Chang-Hwan Lee @. Contents. Motivations. GRB. Gamma-ray bursts. Hypernova. Hypernovae. Spin of Stellar Mass Black Holes. before BH.

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ik10@icranet

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  1. ik10@icranet.org Spin ofStellar Mass Black Holes: Key to Gamma-ray Bursts and Hypernovae In collaboration withG.E. Brown, R.A.M.J. Wijers et al. Chang-Hwan Lee @

  2. Contents Motivations GRB Gamma-ray bursts Hypernova Hypernovae Spin of Stellar Mass Black Holes before BH Stellar evolution before BH formation at birth Formation of rapidly spinning BHs key to GRBs & Hypernovae

  3. GRB Two groups of GRBs • Short Hard Gamma-ray Bursts:Duration time < 2 secNS-NS, NS-LMBH mergers • Long-duration Gamma-ray Bursts:associated with Supernovae This talk

  4. L-GRB What caused GRB/Supernova ? Most-likely Rapidly RotatingBlack Holes Woosley et al. Callapsar: Asymmetric Explosion of a Massive Star Most-likely Rapid-Rotation

  5. L-GRB Gamma Ray Bursts from Black Hole Binaries • Energy > 1051 ergs • Rinit = O(100 km) • M < 30 Msun • dT = ms – min • …… BH-binaries are the most natural sources for rapidly rotating black holes BH Spin energy => Energy in GRBs BH Binaries -> Long-duration GRBs (> 2 sec)

  6. Hypernova Hypernovae in BH binaries (soft X-ray Transients)

  7. Hypernova Compact Stars • Neutron Star [M < 3 Msun; R < 15 km] • Black Holes All buildings in Busan 1 cm3 Density of NS

  8. Hypernova Observed (visible) Black Holes • Center of galaxies (106-109 Msun) • Intermediate Mass Black Holes (100-104 Msun) • Black Hole Binaries (5-10 Msun) (Soft X-ray Transients ) This talk

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

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

  11. Hypernova Brightness of Nova Sco 94 (GRO J1655-40) X-ray & Optical Telescopes

  12. 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?

  13. Hypernova Abundances in the secondary of Nova Sco 94 They had to come from black hole progenitor when it exploded. Hypernova to explain the observations.

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

  15. Hypernova Hypernova Explosions from Rotating BH • High Black Hole Mass ( > 5 Msun)--- Maximum Neutron Star Mass < 2 Msun • Evidences of BH Spin in BH Binaries

  16. Black Holes Spin of Stellar Mass Black Holes : key to GRBs & Hypernovae

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

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

  19. before BH Fate of massive stars Mass of Iron CoreNS/BH mass

  20. before BH Fate of massive stars Close binaries Single star H gas No H-shell He He Q) Mass of the Fe core ?

  21. before BH Fe core mass Black Holes Neutron Star In Close Binaries Heger, Woosley et al.

  22. before BH • In order to form 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 much on the H envelope. Super GiantHe-shell burning Red Giant H-shell burning Merge low-mass Fe core high-mass Fe core Neutron Star Black Holes

  23. before BH Case C HMBH Case B NS/LMBH A Schaller et al.

  24. at birth Rapidly Rotating Black Holes • Tidal interaction : Synchronization of BH-progenitor Spin & Binary Orbital Period • Rapidly rotating BH with large Kerr parameter

  25. at birth Tidal interaction Fe rapidlyspinning BH

  26. at birth Kerr parameter (Lee,Brown,Wijers, ApJ 2002) Preexplosion orbital period (days)

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

  28. at birth Innermost stable circular orbit Fabian Miniutti Schwarzschild BH Kerr BH Line Intensity

  29. at birth • Rapidly spinning black holes at birth Shafee et al. (2006) 4U 1543-47GRO J1655-40 Sources for GRB & Hypernovae at birth Preexplosion orbital period (days)

  30. at birth Reconstructed BH Binaries at Birth (before accretion) GRBs/Hypernovae Rapidly spinning BHs

  31. Conclusions • Spin of Stellar Mass BH in 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 • Rapidly-Spinning BH can power both GRB & Hypernovae • Long-time scale GRBs and Hypernovae :- Short orbital period ( P<0.5 day) HMBH binaries are the remnants of long-duration GRBs and Hypernovae

  32. Thank you

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