Gamma-Ray Bursts (GRBs) are cosmic explosions that occur about oncea day somewhere in the universe. They were discovered by chance in the late1960s, and only in the early 1990s did we obtain strong evidence that theywere occurring in other galaxies, which implied stupendous energies (in a fewseconds they produce what a whole galaxy like our Milky Way emits in a year!).They must thus involve extreme conditions and physical processes. In the lasttwo decades or so, they have become one of the hottest topics of astrophysics,especially when we started detecting them at record-breaking distances(redshifts of almost 10).

Inthis seminar, I will give a broad overview of this Gamma-Ray Burst phenomenon,presenting its main physical features and mechanisms and raising the questionsthat today constitute the main avenues of research on this topic. I will also mention some of the contributions that my collaborators and Ihave made on specific aspects of this big topic.

For more information, contact selkhatib@aus.edu.