Implication of Temporal Structure in GRB

Abstract

The highly variable temporal structure observed in most GRBs provides us with unexpected clues. We show that variable GRBs cannot be produced by external shocks models and consequently cannot be produced by an ``explosive'' inner engine. The observed temporal structure must reflect the activity of the inner engine that must be producing unsteady and irregular ``wind'' which is converted to radiation via internal shocks.

3 page latex file. Complete uuencoded compressed PS file is also available at ftp://shemesh.fiz.huji.ac.il or at http://shemesh.fiz.huji.ac.il/papers/PaS_texas.uu to appear in Proc. of 18th Texas symposium