Four Years of Swift: Gamma Ray Bursts, Active Galactic Nuclei and Other Highlights

Presented by Dirk Grupe, Pennsylvania State University

Swift, one of NASA's most successful missions, was launched exactly 4 years ago today. The primary scientific objectives are to determine the origin of Gamma Ray Bursts (GRB) and to pioneer their use as probes of the early universe. The Swift key characteristics are the rapid response to newly detected GRBs and rapid data dissemination. Swift has revolutionized our understanding of GRBs. It has found that the majority of GRBs show a typical decay behavior with a steep initial decay followed by a plateau phase and another steep decay phase. About half of the GRB afterglows also display very strong flares right after the burst and even at later times suggesting strong internal engine activity. In my talk I will give a decription how Swift works and summarize some of its major discoveries. I will also discuss our observations of Active Galactic Nuclei (AGN) in order to study the spectral energy distribution. Swift with its unique multiwavelength capacity makes it possible to study the optical/UV and X-ray emission of AGN simultaneously. Because AGN are highly variable in X-rays as well as in the UV, simultaneous observations are crucial to understand the spectral energy distribution. I will present an overview of results from Swift on a large sample of AGN.