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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"

28232 results found.

  1. GRB 091029: Swift-BAT refined analysis
  2. GRB 091029: Enhanced Swift-XRT position
  3. GRB091024 optical observations
  4. GRB 091029: GROND Detection of the Optical/NIR Afterglow
  5. GRB 091029: Swift detection of a burst with an optical counterpart
  6. GRB 091020: Fermi GBM observation
  7. GRB 091026: Suzaku WAM observation of the prompt emission
  8. GRB 091026: GROND Upper Limits
  9. GRB 091026: Swift-BAT refined analysis
  10. Radio afterglow detection from GRB 091020
  11. GRB 091026: Swift/UVOT Upper Limits
  12. GRB 091026: Swift-XRT refined analysis
  13. GRB 091026: Enhanced Swift-XRT position
  14. Konus-Wind and Konus-RF observations of GRB 091024
  15. GRB 091026: Swift detection of a Gamma Ray Burst
  16. GRB091024 Swift/UVOT Upper Limits
  17. GRB 091024: Super-LOTIS early observations
  18. GRB 091024: Swift-BAT refined analysis
  19. GRB 091024: Fermi GBM Observations
  20. GRB 091024: Swift-XRT team refined analysis
  21. GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
  22. GRB 091024: GRAS004 optical observations
  23. GRB 091020: Swift-XRT refined analysis
  24. GRB 091018: Swift XRT refined analysis
  25. GRB091020 Swift/UVOT observations
  26. GRB 091020, Swift-BAT refined analysis
  27. GRB 091020: Enhanced Swift-XRT position
  28. GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
  29. GRB 091020: Swift detection of a burst with an optical afterglow
  30. GRB 091018: Skynet/PROMPT Observations of Fading
  31. Konus-RF observation of GRB 091018
  32. GRB 091018 : Faulkes Telescope South Observations
  33. GRB091018: Swift/UVOT observations
  34. GRB 091018: Swift-BAT refined analysis
  35. GRB 091018: Enhanced Swift-XRT position
  36. GRB 091018: ROTSE-III Detection of Optical Counterpart
  37. GRB 091015: Skynet/PROMPT Observations
  38. GRB 091018: Swift detection of a burst with optical afterglow
  39. GRB 091010: optical obsevation
  40. GRB 090726 R band observations
  41. GRB 091010: optical afterglow candidate rejection
  42. GRB 091010: Swift-XRT refined analysis
  43. GRB 091010: Suzaku WAM observation of the prompt emission
  44. GRB 091010: AGILE-MCAL measurement and GRID upper limit
  45. Radio observation of GRB090927 with ATCA
  46. Radio observation of GRB090926a with ATCA
  47. Radio observation of GRB080916c with ATCA
  48. GRB 091010: Fermi GBM observation
  49. GRB 091010: Faulkes Telescope North observations
  50. GRB 090531A: Skynet/PROMPT Observations
  51. GRB 090530A: Skynet/DSO Detections
  52. GRB 091010: Enhanced XRT position
  53. GRB 091010 optical upper limits
  54. Detection of a short GRB 090929A by RT-2 Experiment
  55. GRB 091010: GROND afterglow candidate
  56. GRB 091010: Swift/UVOT Upper Limits
  57. GRB 091010: Swift-XRT position
  58. GRB 090910: SuperAGILE Localization of a Long GRB
  59. GRB 090926A: Skynet/PROMPT Observations of Day 6 - 11 Fading
  60. GRB 090518: Skynet/PROMPT Observations
  61. Short-Duration GRB 090621: Skynet/Dolomiti Observations
  62. GRB 090904A: afterglow confirmation
  63. GRB 090812: Skynet/PROMPT and GORT Observations
  64. GRB 091003A: Suzaku WAM observation of the prompt emission
  65. GRB 090926B: Skynet/PROMPT Observations
  66. GRB 091003: WHT ACAM observations
  67. GRB 090929B: Suzaku WAM observation of the prompt emission
  68. GRB 090929A: Suzaku WAM observation of the prompt emission
  69. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  70. GRB 091003: Skynet/DSO Observations
  71. GRB 091003: UVOT-enhanced XRT position
  72. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  73. GRB 091003A: Fermi LAT detection
  74. GRB 090926A: Skynet/PROMPT Observations of Day 4 - 6 Fading Rate
  75. GRB 091003A: Fermi GBM detection
  76. GRB 090926A: Skynet/PROMPT Observations of Post-Peak Fading
  77. GRB 090929A, Swift-BAT refined analysis
  78. GRB 090929B, Swift-BAT refined analysis
  79. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  80. GRB 090929A: Swift-XRT non-detection
  81. Konus-Wind observation of GRB 090929B
  82. GRB 090929B: Swift-XRT refined analysis
  83. GRB 090929B: Gemini-N upper limits
  84. GRB 090929B: Skynet/DSO Observations
  85. GRB 090929B: Swift/UVOT Observations
  86. GRB 090929B: RAPTOR Discovery of Optical Counterpart
  87. GRB 090929A BAT location of the Fermi GBM burst
  88. Correction: GRB 090929B: Enhanced Swift-XRT position
  89. GRB 090929: Enhanced Swift-XRT position
  90. GRB 090929B: Swift detection of a burst
  91. GRB 090929A: Fermi GBM detection
  92. GRB090926A: Swift-XRT refined analysis
  93. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  94. GRB 090927: Zadko Telescope observations
  95. GRB 090927, Swift-BAT refined analysis of the possibly short burst
  96. Swift/UVOT observations of GRB 090927
  97. GRB 090926A: Skynet/PROMPT Continued Observations
  98. GRB 090927: Swift XRT refined analysis
  99. GRB 090926A: Suzaku WAM observation of the prompt emission
  100. GRB 090927: Enhanced Swift-XRT position

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