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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').

18174 results found.

  1. GRB050215A: ROTSE-III Optical Observations
  2. short/hard GRB 050202, optical observations
  3. GRB 050128: Radio observations
  4. Further analysis of the short Swift-BAT GRB 050202
  5. GRB 050202: Second epoch radio observations
  6. GRB050202: Radio Observations
  7. GRB 050202: Short burst detected by Swift-BAT
  8. SGR1806-20: Swift-BAT detection of a large normal burst
  9. GRB050128: Faulkes Telescope South observations
  10. GRB050128,optical observations
  11. GRB050126: Updated Swift XRT Position
  12. GRB 050126: Radio Observations
  13. GRB050128 Swift-BAT observations
  14. GRB 050128: Swift XRT prompt afterglow position
  15. GRB 050124: K-band afterglow observations
  16. GRB050126: MASTER optical limit for KECK OT
  17. GRB050126: Burst Parameters Measured by BAT
  18. GRB050126: MASTER optical observations
  19. GRB 050126: Prompt XRT detection and localization
  20. GRB050124: No Swift UVOT Detection of Afterglow Emission
  21. GRB 050117a: Radio Observations
  22. GRB050124,optical observation
  23. GRB050124: Updated Swift XRT Position and Fluxes
  24. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  25. GRB050124: Refined BAT position, spectral and fluence information
  26. GRB050124: Swift-BAT position of a double-peaked burst
  27. GRB050117a: Radio Observations
  28. GRB050117a: Refined analysis
  29. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  30. GRB050117b: Swift-BAT detection of a weak burst
  31. GRB050117: optical observation
  32. GRB 050117, I-band observations
  33. GRB 050117: Optical observation
  34. GRB050117: Refined XRT position
  35. GRB050117: MASTER optical observations
  36. MASTER:GRB050117 SWIFT
  37. GRB050117: Swift-BAT detection of a long multi-peaked burst
  38. GRB050117: Swift XRT Position
  39. SGR1806-20: Swift-BAT observations of two additional bursts
  40. SGR 1806-20, RHESSI observations of the 041227 giant flare
  41. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  42. GRB 041217: Optical observations
  43. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  44. GRB041228: ROTSE-III Optical Observations
  45. GRB041228: Swift-BAT detection of a burst
  46. GRB041219; RXTE ASM Observations
  47. NIR Observations of GRB 041219
  48. GRB041226: ROTSE-III Optical Observations
  49. GRB041226: Swift-BAT detection of a burst
  50. GRB041223: decay of the afterglow
  51. GRB041224: ROTSE-III Optical Observations
  52. GRB 041223: XRT afterglow spectrum and light curve
  53. GRB 041223 Fluence measured by Swift-BAT
  54. GRB041224: Swift-BAT detection of a soft burst
  55. GRB041223: optical and NIR observations with REM
  56. Swift-BAT Time History of GRB041219
  57. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  58. GRB041223: ROTSE-III Optical Observations
  59. GRB041223: Swift-BAT detection of a bright long burst
  60. GRB041220: Swift-BAT burst
  61. GRB 041219 Optical Observations
  62. GRB041219c: Third Burst in One Day from Swift-BAT
  63. GRB041219b: A Swift-BAT burst
  64. Swift-BAT detection of the bright long burst GRB041219
  65. GRB041217: optical limit 30 min after GRB
  66. GRB041217: Optical Observations
  67. GRB041217: NIR and optical observations with REM
  68. GRB041217: P60 Optical Observations
  69. GRB041217: Infrared Observations
  70. GRB041217: The First GRB Located On-Board Swift
  71. GRB040916: Optical observations
  72. GRB040422: optical and NIR observations at the VLT
  73. GRB040223, improved XMM position
  74. SN 2003jd (SN/GRB?) - possible association with GRB 030929

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