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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21525 results found.

  1. GRB041224: ROTSE-III Optical Observations
  2. GRB 041223: XRT afterglow spectrum and light curve
  3. GRB 041223 Fluence measured by Swift-BAT
  4. GRB041224: Swift-BAT detection of a soft burst
  5. GRB041223: optical and NIR observations with REM
  6. Swift-BAT Time History of GRB041219
  7. GRB 041223: Detection of Optical Transient with LCO40
  8. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  9. GRB041223: ROTSE-III Optical Observations
  10. GRB041223: Swift-BAT detection of a bright long burst
  11. GRB041220: Swift-BAT burst
  12. GRB 041219 Optical Observations
  13. GRB041219c: Third Burst in One Day from Swift-BAT
  14. GRB041219b: A Swift-BAT burst
  15. Swift-BAT detection of the bright long burst GRB041219
  16. GRB041217: optical limit 30 min after GRB
  17. GRB041217: Optical Observations
  18. GRB041217: NIR and optical observations with REM
  19. GRB041217: P60 Optical Observations
  20. GRB041217: Infrared Observations
  21. GRB041217: The First GRB Located On-Board Swift
  22. GRB040916: Optical observations
  23. GRB040422: optical and NIR observations at the VLT
  24. GRB040223, improved XMM position
  25. SN 2003jd (SN/GRB?) - possible association with GRB 030929

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Download all Circulars as a .tar.gz archive (updated once a day):
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