The First Survey of X-ray Flares from Gamma Ray Bursts Observed by Swift: Spectral Properties and Energetics

Understand

Observations of gamma ray bursts (GRBs) with Swift produced the initially surprising result that many bursts have large X-ray flares superimposed on the underlying afterglow.

• The flares were sometimes intense, had rapid rise and decay phases, and occurred late relative to the ``prompt'' phase.
• Some remarkable flares are observed with fluence comparable to the prompt GRB fluence.
• Many GRBs have several flares, which are sometimes overlapping.