Cosmic Gamma-Ray Bursts, Their Afterglows, and Their Host Galaxies

Gamma-ray bursts are the most luminous explosions in the Universe, and their origin and mechanism are the focus of intense research and debate. More than three decades after their discovery, and after pioneering breakthroughs from space and ground experiments, their study is entering a new phase with the recently launched Swift satellite. The interplay between these observations and theoretical models of the prompt gamma ray burst and its afterglow is reviewed.

Present knowledge indicates that gamma-ray bursts are linked with massive stars. They will become invaluable probes of the early universe and galaxy formation. In the future, it will be possible to use gamma-ray bursts for two purposes: 1) to probe the history of massive star formation in the Universe by the rate of occurence of gamma-ray bursts, and 2) for the study of galaxy evolution at all lookback times by determining the nature of the galaxy hosts. Because gamma-rays ar...

In the first part of this paper we summarize the discovery and the early study of the gamma-ray bursts. The second part studies the spatial and sky distribution of the bursters. The brightness distribution is also studied. In the conclusion we discuss that these are supporting the cosmological origin of the gamma-ray bursts.

Gamma-ray bursts (GRBs) are among the most violent occurrences in the universe. They are powerful explosions, visible to high redshift, and thought to be the signature of black hole birth. They are highly luminous events and provide excellent probes of the distant universe. GRB research has greatly advanced over the past 10 years with the results from Swift, Fermi and an active follow-up community. In this review we survey the interplay between these recent observations and t...

We show that, if many GRBs are indeed produced by the collapse of massive stars, GRBs and their afterglows provide a powerful probe of the very high redshift (z > 5) universe.

Gamma-ray bursts are the most luminous and probably the most relativistic events in the universe. The last few years have seen a tremendous increase in our knowledge of these events, but the source of the bursts still remains elusive. I will summarise recent progress in this field with special emphasis on our understanding of the possible progenitor systems.

The discovery of X-ray, optical and radio afterglows of GRBs provides an important tool for understanding these sources. Most current models envisage GRB as arising in a cataclysmic stellar event leading to a relativistically expanding fireball, where particle acceleration at shocks lead to nonthermal radiation. The predictions of this scenario are in substantial agreement with the bulk of the observations. In addition, the data show a diversity of finer structure behavior, w...

We show that, if the long GRBs are produced by the collapse of massive stars, GRBs and their afterglows may provide a powerful probe of cosmology and the early universe.

We show that, if the long GRBs are produced by the collapse of massive stars, GRBs and their afterglows may provide a powerful probe of cosmology and the early universe.

We show that, if the long GRBs are produced by the collapse of massive stars, GRBs and their afterglows may provide a powerful probe of cosmology and the early universe.