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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

14854 results found.

  1. Swift Trigger 381591: Uncatalogued UVOT Source
  2. GRB 091230: Swift/UVOT Observations
  3. Trigger 381591: Swift detection of a possible burst
  4. Trigger 381434: Swift detection of a possible burst
  5. GRB 091221: UVOT Confirmation of an Optical Afterglow
  6. GRB 091221: ROTSE-III Detection of Optical Counterpart
  7. GRB 091221: Swift detection of a burst
  8. Trigger 379449: Swift detection of a possible burst
  9. GRB091208B: Swift/UVOT refined analysis
  10. GRB 091208B: Swift detection of a burst with an optical afterglow
  11. GRB 091208: Swift detection of a burst
  12. GRB 091117: Chandra Observations
  13. Short X-ray Transient Detection by MAXI/GSC
  14. GRB 091123: Fermi GBM detection of a very long burst
  15. GRB 091126B: Fermi GBM detection
  16. GRB 091126: Fermi GBM detection
  17. GRB 091130B: SDSS galaxy at XRT location
  18. GRB 091130B: Swift detection of a burst
  19. GRB 091130: Swift detection of a possible burst
  20. GRB 091128: Fermi GBM detection
  21. GRB 091127: Fermi GBM detection
  22. GRB 091127: Swift-XRT afterglow detection and analysis
  23. GRB 091127: REM NIR afterglow detection
  24. GRB 091127: Swift/UVOT Detection of an Optical Afterglow
  25. GRB 091127: Liverpool Telescope afterglow candidate
  26. GRB 091127: Swift detection of a burst
  27. GRB 091120: MAXI GSC detection
  28. GRB 091031: Fermi LAT detection of a faint burst
  29. GRB 091112: Swift detection of a possible burst
  30. GRB 091109B: Optical limits from Watcher
  31. GRB 091109B: Swift detection of a short burst
  32. GRB091109: Correction to GCN 10139
  33. GRB 091030: Fermi GBM detection
  34. GRB 091109: BOOTES-3 observations
  35. GRB091109: REM detection of the NIR afterglow
  36. GRB 091109: Swift detection of a burst with optical afterglow
  37. GRB 091104: Swift detection of a burst
  38. Fermi LAT Upper Limits on GRB 091010
  39. GRB 091102 : Faulkes Telescope South Upper Limits
  40. GRB 091102: BOOTES-3 observations
  41. GRB 091102: Swift detection of a burst
  42. GRB 091031: Fermi GBM detection
  43. GRB 091024: Fermi LAT upper limits
  44. GRB 090920: Skynet/DSO Detection
  45. GRB091029: Swift/UVOT observations
  46. GRB 091029: GROND Detection of the Optical/NIR Afterglow
  47. GRB 091029: Swift detection of a burst with an optical counterpart
  48. GRB 091020: Late TLS detection
  49. Radio afterglow detection from GRB 091020
  50. GRB 091026: Swift detection of a Gamma Ray Burst
  51. GRB 091024: KAIT optical afterglow observations
  52. GRB 091024: Faulkes Telescope North Afterglow Candidate
  53. GRB 091024: Swift detection of a burst
  54. GRB091020 Swift/UVOT observations
  55. GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
  56. GRB 091020: Swift detection of a burst with an optical afterglow
  57. GRB 091018: VLT/X-shooter spectra
  58. GRB091018: Swift/UVOT observations
  59. GRB 091018: ROTSE-III Detection of Optical Counterpart
  60. GRB 091018: Swift detection of a burst with optical afterglow
  61. GRB 090726 R band observations
  62. GRB 091010: RXTE detection
  63. Detection of a short GRB 090929A by RT-2 Experiment
  64. GRB 091003: Lick observations and possible SDSS host galaxy
  65. GRB 091003: WHT ACAM observations
  66. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  67. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  68. GRB 091003A: Fermi LAT detection
  69. GRB 091003A: Fermi GBM detection
  70. GRB 090929A: Swift-XRT non-detection
  71. GRB 090929B: Swift/UVOT Observations
  72. GRB 090929B: Swift detection of a burst
  73. GRB 090929A: Fermi GBM detection
  74. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  75. GRB 090926B: Fermi GBM detection
  76. GRB 090927: Swift/UVOT detection of an optical afterglow
  77. GRB 090927: Swift detection of a short burst
  78. GRB 090926B: MAXI GSC detection
  79. GRB 090926A: Swift/UVOT detection of an optical afterglow
  80. GRB 090926B: Swift detection of a burst
  81. GRB 090926: Fermi LAT detection
  82. GRB 090926: Fermi GBM detection
  83. GRB 090925: Fermi GBM detection
  84. GRB 090922A: Fermi GBM detection
  85. GRB 090915: GROND upper limits
  86. GRB 090915: SARA detection of afterglow candidate
  87. GRB 090915: Swift/UVOT detection of an optical afterglow candidate
  88. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  89. GRB 090916: Swift detection of a short burst
  90. GRB 090915 Swift-BAT detection of a burst in ground analysis
  91. GRB 090827: Confirmation of the X-ray afterglow
  92. GRB 090912: Swift detection of a burst
  93. GRB 090910: Fermi GBM detection
  94. GRB 090904B: GROND detection of the optical afterglow
  95. GRB 090904B: Fermi GBM detection
  96. GRB 090902B: VLA radio detection
  97. GRB 090904B: Swift detection of a burst
  98. GRB 090904: Swift detection of a burst
  99. GRB 090902B: ROTSE-III Detection of Optical Afterglow
  100. GRB 090902B: Swift/UVOT refined analysis

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