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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"

19662 results found.

  1. GRB 091020: Swift-XRT refined analysis
  2. GRB 091018: Swift XRT refined analysis
  3. GRB091020 Swift/UVOT observations
  4. GRB 091020, Swift-BAT refined analysis
  5. GRB 091020: Enhanced Swift-XRT position
  6. GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
  7. GRB 091020: Swift detection of a burst with an optical afterglow
  8. GRB 091018: Skynet/PROMPT Observations of Fading
  9. Konus-RF observation of GRB 091018
  10. GRB 091018 : Faulkes Telescope South Observations
  11. GRB091018: Swift/UVOT observations
  12. GRB 091018: Swift-BAT refined analysis
  13. GRB 091018: Enhanced Swift-XRT position
  14. GRB 091018: ROTSE-III Detection of Optical Counterpart
  15. GRB 091018: Swift detection of a burst with optical afterglow
  16. GRB 090726 R band observations
  17. GRB 091010: Swift-XRT refined analysis
  18. Radio observation of GRB090927 with ATCA
  19. GRB 091010: Fermi GBM observation
  20. GRB 090531A: Skynet/PROMPT Observations
  21. GRB 090530A: Skynet/DSO Detections
  22. GRB 091010: Enhanced XRT position
  23. GRB 091010: GROND afterglow candidate
  24. GRB 091010: Swift/UVOT Upper Limits
  25. GRB 091010: Swift-XRT position
  26. GRB 090518: Skynet/PROMPT Observations
  27. Short-Duration GRB 090621: Skynet/Dolomiti Observations
  28. GRB 090812: Skynet/PROMPT and GORT Observations
  29. GRB 091003: Lick observations and possible SDSS host galaxy
  30. GRB 090926B: Skynet/PROMPT Observations
  31. GRB 090929B: Suzaku WAM observation of the prompt emission
  32. GRB 091003: Swift-XRT confirmation of fading afterglow
  33. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  34. GRB 091003: UVOT-enhanced XRT position
  35. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  36. GRB 091003: Swift XRT analysis
  37. GRB 091003A: Fermi LAT detection
  38. GRB 090929A: Swift/UVOT Observations
  39. GRB 090929A, Swift-BAT refined analysis
  40. GRB 090929B, Swift-BAT refined analysis
  41. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  42. GRB 090929A: Swift-XRT non-detection
  43. Konus-Wind observation of GRB 090929A
  44. Konus-Wind observation of GRB 090929B
  45. GRB 090927: Fermi GBM observation
  46. GRB 090929B: Swift-XRT refined analysis
  47. GRB 090929B: Skynet/DSO Observations
  48. GRB 090929B: Swift/UVOT Observations
  49. Konus-RF observation of GRB 090929A
  50. GRB 090929B: RAPTOR Discovery of Optical Counterpart
  51. GRB 090929A BAT location of the Fermi GBM burst
  52. Correction: GRB 090929B: Enhanced Swift-XRT position
  53. GRB 090929: Enhanced Swift-XRT position
  54. GRB 090929B: Swift detection of a burst
  55. GRB090926A: Swift-XRT refined analysis
  56. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  57. GRB 090926B: Fermi GBM detection
  58. GRB 090927: Zadko Telescope observations
  59. GRB 090927, Swift-BAT refined analysis of the possibly short burst
  60. Swift/UVOT observations of GRB 090927
  61. GRB 090927: Swift XRT refined analysis
  62. GRB 090927: Enhanced Swift-XRT position
  63. GRB090926B: Swift/UVOT Upper Limits
  64. GRB090926A: Swift/UVOT observations
  65. GRB 090927: Swift/UVOT detection of an optical afterglow
  66. GRB 090927: Swift detection of a short burst
  67. GRB 090926B: MAXI GSC detection
  68. GRB 090926B: Swift XRT refined analysis
  69. GRB 090926B: Swift-BAT refined analysis
  70. GRB 090926A: Swift/UVOT detection of an optical afterglow
  71. GRB 090926A: Skynet/PROMPT Discovery of the Optical Afterglow
  72. GRB090926A: UVOT-enhanced XRT position
  73. GRB 090926B: Swift detection of a burst
  74. GRB 090926: Fermi LAT detection
  75. GRB090904B : IRSF NIR upper limit
  76. Swift returns to normal operations
  77. GRB 090715B: Skynet/PROMPT Detections
  78. GRB 090916: Swift-XRT upper limit
  79. GRB 090807: Skynet/DSO Observations
  80. Swift-BAT temporarily off-line for a few days
  81. Short-Duration GRB 090916: Skynet/PROMPT Observations
  82. GRB 090912: optical observation
  83. GRB 090915: Swift/UVOT detection of an optical afterglow candidate
  84. GRB 090916, Swift-BAT refined analysis
  85. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  86. GRB 090916: Swift detection of a short burst
  87. GRB 090915 Swift-BAT detection of a burst in ground analysis
  88. GRB 090827: Confirmation of the X-ray afterglow
  89. GRB 090912: Swift-XRT refined analysis
  90. GRB 090912, Swift-BAT refined analysis
  91. GRB 090912: Swift/UVOT Upper Limits
  92. GRB 090912: Enhanced Swift-XRT position
  93. GRB 090912: Swift detection of a burst
  94. GRB 090814A: Skynet/DSO & GORT Observations
  95. GRB 090823: Swift XRT confirmation of the X-ray afterglow
  96. GRB 090904B: GROND detection of the optical afterglow
  97. GRB 090904A: Swift/UVOT Refined Analysis
  98. GRB 090904B: Swift/UVOT Refined Analysis
  99. GRB 090904B: Fermi GBM detection
  100. GRB 090904A: Swift-XRT refined analysis

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