Joint Astrophysics Colloquium

Joint Astrophyscis Seminar

Gamma-Ray Bursts in the Swift Era

Rosalba Perna

JILA/U. Colorado, Bolder

The launch of the Swift satellite has marked the beginning of a new era in Gamma-Ray Burst (GRB) science. I will start with a brief review of the status of GRB observations prior to Swift, and our understanding of their progenitors for the class of long bursts. I will then discuss how GRB data during the Swift era are improving our understanding of the properties of the progenitors of long GRBs, shedding light on the nature of short bursts, and impacting several areas of cosmology. In particular, I will discuss how GRBs can be used to trace the evolution of the mean density of the medium with redshift and the properties of dust in high-z galaxies. Dectection of GRBs at very high redshifts can help set constraints on the small-scale power spectrum of density fluctuations. Statistical studies of short GRBs can improve our understanding of evolutionary binary scenarios. Finally, I will discuss how the new, unexpected observations of X-ray flares are beginning to probe the extreme conditions of the GRB engine.