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Long-duration gamma-ray bursts (GRBs) are powerful cosmic explosions, signaling the death of massive stars. Among them, GRB 221009A is by far the brightest burst ever observed. Because of its enormous energy (Eiso≈ 1055erg) and proximity (z≈ 0.15), GRB 221009A is an exceptionally rare event that pushes the limits of our theories. We present multiwavelength observations covering the first 3 months of its afterglow evolution. The x-ray brightness decays as a power law with slope ≈t−1.66, which is not consistent with standard predictions for jetted emission. We attribute this behavior to a shallow energy profile of the relativistic jet. A similar trend is observed in other energetic GRBs, suggesting that the most extreme explosions may be powered by structured jets launched by a common central engine.
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This content will become publicly available on August 1, 2026
Two-component jet model for the afterglow emission of GRB 201216C and GRB 221009A and implications for jet structure of very-high-energy gamma-ray bursts
- PAR ID:
- 10652366
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of High Energy Astrophysics
- Volume:
- 48
- Issue:
- C
- ISSN:
- 2214-4048
- Page Range / eLocation ID:
- 100415
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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