Swift X-ray afterglows: Where are the X-ray jet breaks?

D. N. Burrows, J. Racusin

Research output: Contribution to journalArticlepeer-review

20 Scopus citations


We examine the Swift/X-ray Telescope (XRT) light curves from the first ∼ 150 Gamma-Ray Burst (GRB) afterglows. Although we expected to find jet breaks at typical times of 1-2 days after the GRB, we find that these appear to be extremely rare. Typical light curves have a break in the slope at about 104 s, followed by a single power law decay whose slope is much too shallow to be consistent with expectations for jet breaks. X-ray light curves typically extend out to ∼ 10 days without any further breaks, until they become too faint for the XRT to detect. In some extreme cases, light curves extend out to more than two months without evidence for jet breaks. This raises concerns about our understanding of afterglow and jet dynamics, and of GRB energetics.

Original languageEnglish (US)
Pages (from-to)1273-1287
Number of pages15
JournalNuovo Cimento della Societa Italiana di Fisica B
Issue number10-11
StatePublished - Oct 2006

All Science Journal Classification (ASJC) codes

  • General Physics and Astronomy


Dive into the research topics of 'Swift X-ray afterglows: Where are the X-ray jet breaks?'. Together they form a unique fingerprint.

Cite this