| A gamma-ray burst(GRB) is the sudden and transient flash of soft gamma rays coming from some random point in the space. The gamma-ray durations range from 10-3 sec to 103 sec. The emission energy is mainly in the range of 0.1100 MeV. The overall observed fluences range from 10-7ergs/cm2 to 10-4 ergs/cm2. Ever since its being discovered in 1967, GRBs are always mysteries. Twenty years after the discovery, they were undetected at any wavelengths other than gamma-rays, which provided poor directional information and hence no direct clues on where they originated. It was not until 1997 that owing to the Italy and Netherlands satellite, BeppoSAX, succeeded in detecting X-rays afterglows which after a delay of some hours yielded sufficiently accurate positions for large ground-based telescope follow-up observation and from which, GRBs were resolved to be located at cosmological distances.Observations show that gamma-ray bursts' electromagnetic energy output during tens of seconds is comparable to that of our entire Milky Way over a few years. This prodigious energy released in a very short time can't be produced by nuclear fusion. The current interpretation of how this jumbo energy release is produced is that a large amount of gravitational energy is released in a few seconds and tens of kilometers region by cataclysmic stellar event. Most of the energy would escape as thermal neutrinos, while another fraction is emitted as gravitational waves. This sudden energy liberation would result in a very high temperature fireball expanding at highly relativistic speeds. To explain the diverse and irregular light curve of the GRB's prompt radiation and the observed...
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