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Exploring Gamma-Ray Bursts: Origins, Types, and Detection Mechanisms

This document provides an overview of Gamma-Ray Bursts (GRBs), including their classifications into short-hard and long-duration events. Key topics include the formation of black holes, neutron star mergers, and their significance in gravitational wave detection. The impacts of GRBs on our understanding of the universe and their association with supernovae and hypernovae are discussed. The advancements in detection methods since the 1970s, including the use of spaceborne telescopes like Swift and LIGO, are highlighted. This exploration is essential for the continued study of cosmic phenomena.

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Exploring Gamma-Ray Bursts: Origins, Types, and Detection Mechanisms

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  1. KGRB@ewha Introduction to GRB and Motivation of KGRB Chang-Hwan Lee @

  2. GRB

  3. GRB Introductio to GRB Short Hard GRB Gravitational Wave Detection NS-NS, NS-BH Mergers Long Soft GRB Collapsar / Hypernova Spin of Stellar Mass Black Holes Another class ? Soomin Jeong’s talk

  4. GRB Gamma-ray Bursts

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

  6. GRB

  7. GRB Galactic ?

  8. GRB

  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. L-GRB Long-duration Gamma-ray Bursts

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

  12. 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

  13. 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 !

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

  15. 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

  16. L-GRB Discovery of X-ray BH Binaries X-rays Mass accretion from a companion star to a compact object

  17. L-GRB X-ray & Optical Telescopes Oscillating Brightness (GRO J1655-40)

  18. L-GRB Number of X-ray Sources (enough to explain GRBs) 1970s 1990s  1,000  50,000

  19. L-GRB Hypernovae in BH binaries (soft X-ray Transients)

  20. L-GRB 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?

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

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

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

  24. L-GRB Reconstructed BH Binaries at Birth HN/GRB BH Spin – 10000/sec

  25. L-GRB Q) How to generate chaotic(?) light curves ?Q) Is there a model that explains all the light curves ?

  26. 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) Talk by Prof. Hyun Kyu Lee

  27. SHB Short-Hard Gamma-ray Bursts

  28. Short-hard GRBs SHB hard BATSE Sample • No optical counterpart (?) • Origin • Neutron star merger? • Magnetar flare? • Supernova? short long soft 0.01 1000 1

  29. 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

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

  31. SHB Laser Interferometer Gravitational Wave Observatory LIGO I : in operation (since 2004) LIGO II: in progress (2010 ?)

  32. 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 ? Soomin Jeong’s Talk

  33. SHB Invisible NS/BH binaries by Bethe/Brown/Lee • NS/LMBH is 5 times more dominant than NS/NS due to hypercritical acctetion. • NS/LMBH will increase LIGO detection rate by factor of 10.

  34. SHB Binary Neutron Stars : Observation vs Prediction Black Holes ? Lee et al., ApJ, accepted (2007)

  35. SHB NS-WD binaries

  36. SHB Pulsar J0751+1807 2.1 ± 0.2 solar mass Nice et al., ApJ 634 (2005) 1242. Nice, talk@40 Years of Pulsar, McGill, Aug 12-17, 2007 1.26 +0.14 -0.12 solar mass Loop-hole in Bayesian analysis for WD mass

  37. SHB R0=17 Mpc (initial LIGO), 280 Mpc (advanced LIGO)

  38. SHB

  39. Korean GRB Theory: -- Progenitors -- Central Engine Observations & Experiment -- afterglow observations (SHBs & L-GRBs) -- gamma-ray telescope

  40. Thank you

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