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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').

453 results found.

  1. Retractions of previous Swift-BAT triggers
  2. GRB 061126: Radio Observations
  3. Konus-Wind observation of GRB 061122
  4. GRB 061121: Swift/UVOT Observations
  5. GRB 061110B: Swift/XRT position
  6. GRB 060923C, Swift-BAT partial refined analysis
  7. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  8. GRB 060729: Swift/UVOT Observations
  9. GRB 060708: Swift detection of a burst with an UVOT countpart
  10. GRB050223: Host Galaxy
  11. GRB 060512: REM NIR observations
  12. GRB060428B - SDSS Pre-Burst Observations
  13. GRB 060428B: KAIT observations
  14. GRB 060428b: Optical afterglow candidate
  15. GRB060421: Swift/UVOT observations
  16. GRB 060421: Swift-XRT refined analysis
  17. GRB(?)060421 : XRT position
  18. Konus-Wind observation of GRB 060313
  19. GRB 060219: Swift-BAT refined analysis
  20. Konus-Wind observation of GRB 060124
  21. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  22. GRB 060115: Refined analysis of the Swift-BAT burst
  23. GRB 060111B: Refined analysis of the Swift-BAT burst
  24. Possible GRB 051221B: Swift XRT position
  25. GRB 051211B: Swift XRT confirmation of the afterglow
  26. Konus-Wind observation of GRB 051028
  27. GRB 050827: Swift XRT preliminary analysis results
  28. GRB050712: XRT refined analysis
  29. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  30. GRB 050525: TAROT observations of the early afterglow
  31. GRB 050509B: Swift/XRT refined analysis
  32. Konus-Wind observation of GRB 050401
  33. GRB050126: Burst Parameters Measured by BAT
  34. Second Epoch VLA observations of SGR 1806-20
  35. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  36. IBAS GRB Alerts 1978-1980
  37. GRB040903 - A XRF?
  38. IPN Summary of SGR1806-20 Activity in 2004
  39. IPN triangulation of GRB031127A and B (quasi-simultaneous; large error boxes)
  40. IPN triangulation of GRB030919 (large error box)
  41. XRF030723(=H2777): Chandra Observations
  42. IPN triangulation of GRB030413 (small error box)
  43. GRB 030115: Radio detection of IR candidate
  44. IPN triangulation of GRB021223 (two large error boxes)
  45. GRB021004(=H2380): Revised Localization with HETE Soft X-ray
  46. IPN triangulation of GRB020914 - clarification and additional information
  47. IPN triangulation of GRB020904
  48. IPN triangulation of GRB020715 (=GRB150702)
  49. IPN triangulation of GRB150702
  50. SGR1900+14: Second Burst Localized by HETE
  51. GRB000326, Radio observations
  52. GRB000301C, optical observations
  53. GRB980703 - BeppoSAX/GRBM detection

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