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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').

17878 results found.

  1. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  2. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  3. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  4. GRB050215B: ROTSE-III optical observations
  5. GRB050215A: ROTSE-III Optical Observations
  6. short/hard GRB 050202, optical observations
  7. GRB 050128: Radio observations
  8. Further analysis of the short Swift-BAT GRB 050202
  9. GRB 050202: Second epoch radio observations
  10. GRB050202: Radio Observations
  11. GRB 050202: Short burst detected by Swift-BAT
  12. SGR1806-20: Swift-BAT detection of a large normal burst
  13. GRB050128: Faulkes Telescope South observations
  14. GRB050128,optical observations
  15. GRB050126: Updated Swift XRT Position
  16. GRB 050126: Radio Observations
  17. GRB050128 Swift-BAT observations
  18. GRB 050128: Swift XRT prompt afterglow position
  19. GRB 050124: K-band afterglow observations
  20. GRB050126: MASTER optical limit for KECK OT
  21. GRB050126: Burst Parameters Measured by BAT
  22. GRB050126: MASTER optical observations
  23. GRB 050126: Prompt XRT detection and localization
  24. GRB050124: No Swift UVOT Detection of Afterglow Emission
  25. GRB 050117a: Radio Observations
  26. GRB050124,optical observation
  27. GRB050124: Updated Swift XRT Position and Fluxes
  28. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  29. GRB050124: Refined BAT position, spectral and fluence information
  30. GRB050124: Swift-BAT position of a double-peaked burst
  31. GRB050117a: Radio Observations
  32. GRB050117a: Refined analysis
  33. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  34. GRB050117b: Swift-BAT detection of a weak burst
  35. GRB050117: optical observation
  36. GRB 050117, I-band observations
  37. GRB 050117: Optical observation
  38. GRB050117: Refined XRT position
  39. GRB050117: MASTER optical observations
  40. MASTER:GRB050117 SWIFT
  41. GRB050117: Swift-BAT detection of a long multi-peaked burst
  42. GRB050117: Swift XRT Position
  43. SGR1806-20: Swift-BAT observations of two additional bursts
  44. SGR 1806-20, RHESSI observations of the 041227 giant flare
  45. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  46. GRB 041217: Optical observations
  47. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  48. GRB041228: ROTSE-III Optical Observations
  49. GRB041228: Swift-BAT detection of a burst
  50. GRB041219; RXTE ASM Observations
  51. NIR Observations of GRB 041219
  52. GRB041226: ROTSE-III Optical Observations
  53. GRB041226: Swift-BAT detection of a burst
  54. GRB041223: decay of the afterglow
  55. GRB041224: ROTSE-III Optical Observations
  56. GRB 041223: XRT afterglow spectrum and light curve
  57. GRB 041223 Fluence measured by Swift-BAT
  58. GRB041224: Swift-BAT detection of a soft burst
  59. GRB041223: optical and NIR observations with REM
  60. Swift-BAT Time History of GRB041219
  61. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  62. GRB041223: ROTSE-III Optical Observations
  63. GRB041223: Swift-BAT detection of a bright long burst
  64. GRB041220: Swift-BAT burst
  65. GRB 041219 Optical Observations
  66. GRB041219c: Third Burst in One Day from Swift-BAT
  67. GRB041219b: A Swift-BAT burst
  68. Swift-BAT detection of the bright long burst GRB041219
  69. GRB041217: optical limit 30 min after GRB
  70. GRB041217: Optical Observations
  71. GRB041217: NIR and optical observations with REM
  72. GRB041217: P60 Optical Observations
  73. GRB041217: Infrared Observations
  74. GRB041217: The First GRB Located On-Board Swift
  75. GRB040916: Optical observations
  76. GRB040422: optical and NIR observations at the VLT
  77. GRB040223, improved XMM position
  78. SN 2003jd (SN/GRB?) - possible association with GRB 030929

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