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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').

18145 results found.

  1. GRB050117b: Swift-BAT detection of a weak burst
  2. GRB050117: optical observation
  3. GRB 050117, I-band observations
  4. GRB 050117: Optical observation
  5. GRB050117: Refined XRT position
  6. GRB050117: MASTER optical observations
  7. MASTER:GRB050117 SWIFT
  8. GRB050117: Swift-BAT detection of a long multi-peaked burst
  9. GRB050117: Swift XRT Position
  10. SGR1806-20: Swift-BAT observations of two additional bursts
  11. SGR 1806-20, RHESSI observations of the 041227 giant flare
  12. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  13. GRB 041217: Optical observations
  14. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  15. GRB041228: ROTSE-III Optical Observations
  16. GRB041228: Swift-BAT detection of a burst
  17. GRB041219; RXTE ASM Observations
  18. NIR Observations of GRB 041219
  19. GRB041226: ROTSE-III Optical Observations
  20. GRB041226: Swift-BAT detection of a burst
  21. GRB041223: decay of the afterglow
  22. GRB041224: ROTSE-III Optical Observations
  23. GRB 041223: XRT afterglow spectrum and light curve
  24. GRB 041223 Fluence measured by Swift-BAT
  25. GRB041224: Swift-BAT detection of a soft burst
  26. GRB041223: optical and NIR observations with REM
  27. Swift-BAT Time History of GRB041219
  28. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  29. GRB041223: ROTSE-III Optical Observations
  30. GRB041223: Swift-BAT detection of a bright long burst
  31. GRB041220: Swift-BAT burst
  32. GRB 041219 Optical Observations
  33. GRB041219c: Third Burst in One Day from Swift-BAT
  34. GRB041219b: A Swift-BAT burst
  35. Swift-BAT detection of the bright long burst GRB041219
  36. GRB041217: optical limit 30 min after GRB
  37. GRB041217: Optical Observations
  38. GRB041217: NIR and optical observations with REM
  39. GRB041217: P60 Optical Observations
  40. GRB041217: Infrared Observations
  41. GRB041217: The First GRB Located On-Board Swift
  42. GRB040916: Optical observations
  43. GRB040422: optical and NIR observations at the VLT
  44. GRB040223, improved XMM position
  45. SN 2003jd (SN/GRB?) - possible association with GRB 030929

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