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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

17828 results found.

  1. GRB041226: ROTSE-III Optical Observations
  2. GRB041226: Swift-BAT detection of a burst
  3. GRB041223: decay of the afterglow
  4. GRB041224: ROTSE-III Optical Observations
  5. GRB 041223: XRT afterglow spectrum and light curve
  6. GRB 041223 Fluence measured by Swift-BAT
  7. GRB041224: Swift-BAT detection of a soft burst
  8. GRB041223: optical and NIR observations with REM
  9. Swift-BAT Time History of GRB041219
  10. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  11. GRB041223: ROTSE-III Optical Observations
  12. GRB041223: Swift-BAT detection of a bright long burst
  13. GRB041220: Swift-BAT burst
  14. GRB 041219 Optical Observations
  15. GRB041219c: Third Burst in One Day from Swift-BAT
  16. GRB041219b: A Swift-BAT burst
  17. Swift-BAT detection of the bright long burst GRB041219
  18. GRB041217: optical limit 30 min after GRB
  19. GRB041217: Optical Observations
  20. GRB041217: NIR and optical observations with REM
  21. GRB041217: P60 Optical Observations
  22. GRB041217: Infrared Observations
  23. GRB041217: The First GRB Located On-Board Swift
  24. GRB040916: Optical observations
  25. GRB040422: optical and NIR observations at the VLT
  26. GRB040223, improved XMM position
  27. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  28. SAX J0840.7+2248 Optical Observations

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