1. Kunihito IOKA (Osaka Univ.) 1.Observation 2.Fireball 3.Internal shock 4.Afterglow 5.Jet 6.Central engine 7.Links with other fields 8.Luminosity-lag 9.X-ray flash 10.Summary

2. 1. Observation Gamma-Ray Burst Brightest object Vela satellites in 1967 Origin has been a puzzle

3. ～ 1000 events/yr Angular distribution Isotropic

4. Spatial distribution Homogeneous in Euclidean Inhomogeneous

5. Duration Long-soft Short-hard Long burst Short burst

6. Spectrum Band spectrum Non-thermal

7. Afterglow Beppo-SAX in 1997 X-ray Radio

8. Optical → Redshift Redshift

9. Luminosity Time GRB Summary of observation ～ 1000 events/yr Isotropic, Inhomogeneous ～ 200 keV 10 -3 s ～ 10 3 s : short, long Afterglow X-ray Optical Radio Redshift >msec

10. 2. Fireball Compactness problem Relativistic motion MeV  MeV

11. Fireball +Baryon Thermal

12. Ｃｅｎｔｒａｌ ｅｎｇｉｎｅ Ｏｐｔｉｃａｌｌｙ ｔｈｉｃｋ ｒｅｇｉｏｎ Ｉｎｔｅｒｎａｌ ｓｈｏｃｋｓ Ｅｘｔｅｒｎａｌ ｓｈｏｃｋｓ ？ ＩＳＭ Internal-External shock model time Luminosity

13. 3. Internal shock Two shell collision Kobayashi,Piran&Sari(97) Many shell

14. Time scale Pulse width Pulse interval Nakar&Piran(02)

15. 4. Afterglow External shock Hydrodynamics

16. ① Electron Fermi acceleration ② Magnetic field Relativistic shock Jump condition Electron synchrotron emission

17. Spectrum

18. Collapsar, Hypernova

19. ｒｅｖｅｒｓｅ ｓｈｏｃｋｆｏｒｗａｒｄ ｓｈｏｃｋ Shock emission Optical flash

20. 5. Jet Jet & Relativistic beaming ・ Relativistic beaming ・ Jet Jet in afterglow ：ｓｉｄｅｗａｙｓ ｅｘｐａｎｓｉｏｎ Energy, Event rate, Model

21. Total Break in afterglowPolarization A few %

22. Total energy

23. 6. Central engine ① Ｃｏｌｌａｐｓｅ ｏｆ ｍａｓｓｉｖｅ ｓｔａｒ ② Ｍｅｒｇｅｒｓ ｏｆ ｃｏｍｐａｃｔ ｏｂｊｅｃｔｓ ・Ｂａｒｙｏｎ ｆｒｅｅ ・Ｌｏｃａｔｉｏｎ ｗｉｔｈｉｎ ｈｏｓｔ ｇａｌａｘｉｅｓ ・ＧＲＢ - Ｓｕｐｅｒｎｏｖａ （ｅ. ｇ. ，ＳＮ１９９８ｂｗ） ？Ｈｉｇｈ ａｍｂｉｅｎｔ ｇａｓ ｄｅｎｓｉｔｙ ？？ Collapsar, Hypernova

24. Host galaxy

25. SN1998bw-GRB980425 Lightcurve Fe line

26. 7. Links with other fields CR, HE, HE  Cosmology

27. 8. Luminosity-lag  XX Ｌｕｍｉｎｏｓｉｔｙ Ｔｉｍｅ ・Ｓｔａｎｄａｒｄ ｃａｎｄｌｅ ？ ・Ｂｒｉｇｈｔｅｒ ｔｈａｎ ＳＮｅ Ia ・Ｌｅｓｓ ｅｘｔｉｎｃｔｉｏｎ ApJ,554,L163(01)

29. Viewing angle of a single jet ？ ？ ？ ⇒Ｌｕｍｉｎｏｓｉｔｙ - ｌａｇ ｒｅｌａｔｉｏｎ ？

30. Thin jet Ｅｍｉｓｓｉｖｉｔｙ ～Ｂａｎｄ ｓｐｅｃｔｒｕｍ Ｓｐｅｃｔｒｕｍ

32. Luminosity-Lag Relation Lag:

33. Pulse profile Luminosity-width ＦＲＥＤ（Ｆａｓｔ Ｒｉｓｅ Ｅｘｐｏｎｅｎｔｉａｌ Ｄｅｃａｙ）

34. Viewing angle ① Ｐｅａｋ ｌｕｍｉｎｏｓｉｔｙ - ｓｐｅｃｔｒａｌ ｌａｇ ｒｅｌａｔｉｏｎ ② Ｐｅａｋ ｌｕｍｉｎｏｓｉｔｙ - ｖａｒｉａｂｉｌｉｔｙ ｒｅｌａｔｉｏｎ ③ Ｌｕｍｉｎｏｓｉｔｙ - ｗｉｄｔｈ ｒｅｌａｔｉｏｎ GRB 980425 Ａ ｔｙｐｉｃａｌ ＧＲＢ ⇒Ａｓｓｏｃｉａｔｉｏｎ ｏｆ ＧＲＢｓ ｗｉｔｈ ＳＮｅ

35. 9. X-ray flash

36. Off-axis GRB

37. Flux/Fluence Ratio ApJ,571,L31(02)

38. VolumeViewing angle

39. 10. Summary GRB : Internal shock Afterglow : External shock Jet Viewing angle Various relations, X-ray flash Central engine ??? Collapsar? Merger? CR, HE, HE , GW, Cosmology