Gamma-Ray Burst Early Afterglows

Abstract

The successful launch and operation of NASA's Swift Gamma-Ray Burst Explorer open a new era for the multi-wavelength study of the very early afterglow phase of gamma-ray bursts (GRBs). GRB early afterglow information is essential to explore the unknown physical composition of GRB jets, the link between the prompt gamma-ray emission and the afterglow emission, the GRB central engine activity, as well as the immediate GRB environment. Here I review some of the recent theoretical efforts to address these problems and describe how the latest Swift data give answers to these outstanding questions.Comment: 8 pages, 2 figures, to appear in Proc. of "Astrophysics Sources of High Energy Particles and Radiation" (eds. T. Bulik, G. Madejski and B. Rudak), Torun, Poland, 20-24 June, 200

Gamma-ray burst afterglows

“…That erratic X-ray flares generally require late central engine activities raises the question whether some optical flashes/flares are also due to the same origin (but softer and even less energetic, e.g. Zhang 2005). Recent optical afterglow observations reveal that anomalous optical afterglows seem to be the norm (Stanek et al 2006;Roming et al 2006c).…”