The early afterglow

R. Sari*, T. Piran

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

33 Scopus citations


We calculate the expected spectrum and light curves of the early afterglow. For short GRBs the peak of the afterglow will be delayed, typically, by few dozens of seconds after the burst. The X-ray and γ-ray characteristics of this delayed emission provide a way to discriminate between late internal shocks emission (part of the GRB) and the early afterglow signal. Detection of this delayed emission will prove the internal shock scenario as producing the GRB, and will pinpoint the initial Lorentz factor γ0. In the optical band, the dominant emission arises from the reverse shock. This shock, carries a comparable amount of energy to the forward shock. It radiates this energy at much lower frequencies, producing a short optical flash of 15th magnitude or brighter.

Original languageAmerican English
Pages (from-to)537-538
Number of pages2
JournalAstronomy and Astrophysics Supplement Series
Issue number3
StatePublished - Sep 1999
Externally publishedYes


Dive into the research topics of 'The early afterglow'. Together they form a unique fingerprint.

Cite this