3.  DISCOVERY  EARLY OBSERVATIONS  BATSE / BEPPOSAX  ROTSE / OPTICAL COUNTERPARTS  ENERGIES  SOURCES

4. Vela 5

5. EARLY OBSERVATIONS SCIENTISTS NOTICED ABOUT 10 TO 15 GRB A YEAR. LASTING SEVERAL MILLISECONDS TO SEVERAL MINUTES. TREMENDOUS ENERGIES RANDOM DIRECTIONS DURING THE PEAK INSTANT, THE GRB OUTSHINES THE REST OF THE UNIVERSE IN GAMMA RAYS. EARLY MODEL PROPOSED NEUTRON STARS LOCATED IN THE DISK OF THE MILKY WAY AS A SOURCE.

6. ANIMATION OF A GRB.

7. Compton gamma ray observatory

9. DISTRIBUTION OF GAMMA RAY BURSTS

10. BEPPOSAX

11. BeppoSAX observations of GRB970228. On the Left is the original observation on Feb. 28 th. On Right is the same region of the sky on mar. 3 rd Showing the burst has dimmed.

12. robotic optical transient search experiment (rotse)

13.  within seconds grb’s can emit more energy than the sun will release during its entire 10 billion years of life.  if a large grb occurred within about 3,000 light-years of us, it would be catastrophic to life on Earth. ENERGIES  most of a burst’s energy comes in the form of radiation between 100,000 and1 hundred million electron volts.  even though it was 10 billion light- years away, a Grb990123 produced an optical flash so bright that it could have been seen with a pair of binoculars.

14. Is the energy Beamed?

15. HYPERNOVA

16. Merger of neutron stars

18. Thank you. Any questions?