IL NUOVO CIMENTO DELLA SOCIETAÌ€ ITALIANA DI FISICA. B, GENERAL PHYSICS, RELATIVITY, ASTRONOMY AND MATHEMATICAL PHYSICS AND METHODS
Abstract
X-ray flares are very common features in GRB light curves, and occur from similar to 100 s up to thousands of seconds after the burst, when the prompt-to-afterglow transition is taking place. In the context of external shock, X-ray flares can be ascribed to a thick-shell fireball produced by a long-duration central engine activity. The X-ray flare photons are expected to interact with the forward shock electrons by inverse Compton thus producing high-energy flares that potentially will be detected by GLAST LAT. Such high-energy components could explain the delayed GeV emission detected by EGRET in GRB 940217. Observations with GLAST LAT will give useful information to constrain the origin of X-ray flares.
