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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').

18034 results found.

  1. GRB 041217: Optical observations
  2. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  3. GRB041228: ROTSE-III Optical Observations
  4. GRB041228: Swift-BAT detection of a burst
  5. GRB041219; RXTE ASM Observations
  6. NIR Observations of GRB 041219
  7. GRB041226: ROTSE-III Optical Observations
  8. GRB041226: Swift-BAT detection of a burst
  9. GRB041223: decay of the afterglow
  10. GRB041224: ROTSE-III Optical Observations
  11. GRB 041223: XRT afterglow spectrum and light curve
  12. GRB 041223 Fluence measured by Swift-BAT
  13. GRB041224: Swift-BAT detection of a soft burst
  14. GRB041223: optical and NIR observations with REM
  15. Swift-BAT Time History of GRB041219
  16. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  17. GRB041223: ROTSE-III Optical Observations
  18. GRB041223: Swift-BAT detection of a bright long burst
  19. GRB041220: Swift-BAT burst
  20. GRB 041219 Optical Observations
  21. GRB041219c: Third Burst in One Day from Swift-BAT
  22. GRB041219b: A Swift-BAT burst
  23. Swift-BAT detection of the bright long burst GRB041219
  24. GRB041217: optical limit 30 min after GRB
  25. GRB041217: Optical Observations
  26. GRB041217: NIR and optical observations with REM
  27. GRB041217: P60 Optical Observations
  28. GRB041217: Infrared Observations
  29. GRB041217: The First GRB Located On-Board Swift
  30. GRB040916: Optical observations
  31. GRB040422: optical and NIR observations at the VLT
  32. GRB040223, improved XMM position
  33. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  34. SAX J0840.7+2248 Optical Observations

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