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07.04.27@Ewha. Gamma-ray Bursts and Black Holes. Chang-Hwan Lee @. Contents. Motivations. SHB. Short-hard Gamma-ray burst. L-GRB. Long-duration Gamma-ray bursts. Hypernova. Spin of Stellar Mass Black Holes. before BH. before BH formation. at birth. at the time of BH formation.
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07.04.27@Ewha Gamma-ray Bursts and Black Holes Chang-Hwan Lee @
Contents Motivations SHB Short-hard Gamma-ray burst L-GRB Long-duration Gamma-ray bursts 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
SHB L-GRB Gamma-ray Bursts
SHB L-GRB Gamma-Ray Burst Duration: milli sec - min 1970s : Vela Satellite 1990s: CGRO, Beppo-SAX 2000s: HETE-II, Swift
SHB L-GRB
SHB L-GRB Galactic ?
SHB L-GRB
SHB L-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 !
SHB L-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
SHB Short-Hard Gamma-ray Bursts
Short-hard GRBs SHB hard BATSE Sample • No optical counterpart (?) • Origin • Neutron star merger? • Magnetar flare? • Supernova? short long soft 0.01 1000 1
SHB Short-Hard Gamma-ray Burst : Colliding NS binaries Very Important for Gravitational Waves, too Science 308 (2005) 939
SHB Gravitation Wave from Binary Neutron Star B1913+16 Hulse & Taylor (1975) Effect of Gravitational Wave Radiation 1993 Nobel PrizeHulse & Taylor LIGO was based on one DNS until 2002
SHB Laser Interferometer Gravitational Wave Observatory LIGO I : in operation (since 2004) LIGO II: in progress (2010 ?)
SHB NS (radio pulsar) which coalesce within Hubble time (2003)(2004) (1990) (2004) (1975) (1990)(2000) Not important Globular Cluster : no binary evolution White Dwarf companion
GW & SHB Short-Hard Gamma-ray Bursts (SHBs) • Observed NS-NS binaries are inconsistent with SHBs • Invisible old ( > 6 Gyr) NS binaries are responsible for short-hard gamma-ray bursts (SHBs) Nakar et al. What are the invisible old NS binaries ? Calculation by Soomin Jeong (PNU)
GW & SHB Invisible NS/BH binaries by Bethe/Brown/Lee • NS/LMBH is 10 times more dominant than NS/NS due to hypercritical acctetion. • NS/LMBH will increase LIGO detection rate by factor of 20.
GW & SHB Final primary mass Hypercritical accretion
GW & SHB R0=17 Mpc (initial LIGO), 280 Mpc (advanced LIGO)
L-GRB Long-duration Gamma-ray Bursts
L-GRB Long-duration GRBs: Afterglow Host Galaxy Association = Distance Estimation
L-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
L-GRB What caused GRB/Supernova ? Most-likely Black Holes Callapsar: Asymmetric Explosion of a Massive Star Most-likely Rapid-Rotation
L-GRB How to form rapidly spinning black holes? Most likely in BH binaries (Soft X-ray Transients) Companion star can keep BH progenitor rotating Formation of rapidly rotating stellar mass BHs
L-GRB Q) How to generate chaotic(?) light curves ?Q) Is there a model that explains all the light curves ?
L-GRB A Generic GRB Fireball UV/opt/IR/radio gamma-ray X-ray UV/optical IR mm radio gamma-ray central photosphere internal external shocks engine shocks (reverse & forward)
Hypernova Hypernovae in BH binaries (soft X-ray Transients)
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
Hypernova Theoretical Black Holes ? Einstein’s General Relativity Sun : r = 3 km Earch : r = 9 mm Light cannot escape ! Total Nonsense !?
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 )
Hypernova Discovery of X-ray BH Binaries X-rays Mass accretion from a companion star to a compact object
Hypernova Sources of Strong X-ray in the Universe X-ray emission by accretion • Neutron Stars [M < 3 MSun; R <15 km] • Black Holes • … …
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)
Hypernova BH at the Center of a galaxy (M87) Jet=100000 light year
Hypernova Number of X-ray Sources 1970s 1990s 1,000 50,000
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 !
Hypernova Soft X-ray Transients Black Hole Binaries in our Galaxy Galactic Disk XTE J1118+480
Hypernova X-ray & Optical Telescopes Oscillating Brightness (GRO J1655-40)
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?
Hypernova Abundances in the secondary of Nova Sco They had to come from black hole progenitor when it exploded. Hypernova to explain the observations.
Hypernova Another evidence ? C.M. System velocity (-106 km/s) : Abrupt Mass Loss by Explosion Mg,Si,S,…
Hypernova Hypernova Explosions from Rotating BH Spinning BH (QPOs) High Black Hole Mass ( > 5 Msun) --- Maximum Neutron Star Mass < 2 Msun
Hypernova Related Issues to be clarified • Neutrinos from hypernova • Nucleosynthesis from hypernova • Evidences of asymmetric explosions • Connection to GRBs • … …
Spin of Stellar Mass Black Holes : key to GRBs & Hypernovae
Evidences of Hypernovae in BH Binaries We have seen it twice. What about the other BH Binaries ? Nova Sco, V4641 Sgr
Q) How can we understand the population of SXTs ? MS companion 15 10 MBH (Msun) Evolved companion 5 1 10 Orbital period (days)
Progenitors • Evolution of BH Progenitor before BH Goal at birth after BH • Evolution of Donor Star Current Observation
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)
before BH Mass of Iron CoreNS/BH mass