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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').
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.

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

21769 results found.

  1. GRB 091024: Super-LOTIS early observations
  2. GRB 091024: Fermi GBM Observations
  3. GRB 091024: Swift-XRT team refined analysis
  4. GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
  5. GRB 091024: GRAS004 optical observations
  6. Konus-Wind observations of GRB 091010
  7. GRB091020 Swift/UVOT observations
  8. GRB 091020: Enhanced Swift-XRT position
  9. GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
  10. GRB 091020: Swift detection of a burst with an optical afterglow
  11. GRB 091018: Skynet/PROMPT Observations of Fading
  12. Konus-RF observation of GRB 091018
  13. GRB 091018 : Faulkes Telescope South Observations
  14. GRB 091018: BOOTES-3 observations
  15. GRB091018: Swift/UVOT observations
  16. GRB 091018: Swift-BAT refined analysis
  17. GRB 091018: Enhanced Swift-XRT position
  18. GRB 091015: Skynet/PROMPT Observations
  19. GRB 091018: Swift detection of a burst with optical afterglow
  20. GRB 091010: optical obsevation
  21. GRB 091010: Swift-XRT refined analysis
  22. GRB 091010: Suzaku WAM observation of the prompt emission
  23. Radio observation of GRB090927 with ATCA
  24. Radio observation of GRB090926a with ATCA
  25. Radio observation of GRB080916c with ATCA
  26. GRB 091010: Fermi GBM observation
  27. GRB 090531A: Skynet/PROMPT Observations
  28. GRB 091010: Enhanced XRT position
  29. GRB 091010 optical upper limits
  30. Detection of a short GRB 090929A by RT-2 Experiment
  31. GRB 091010: GROND afterglow candidate
  32. GRB 091010: Swift/UVOT Upper Limits
  33. GRB 090518: Skynet/PROMPT Observations
  34. GRB 090904A: afterglow confirmation
  35. GRB 090812: Skynet/PROMPT and GORT Observations
  36. GRB 091003A: Suzaku WAM observation of the prompt emission
  37. GRB 090926B: Skynet/PROMPT Observations
  38. GRB 091003: WHT ACAM observations
  39. Konus-Wind observation of GRB 091003A
  40. GRB 090929B: Suzaku WAM observation of the prompt emission
  41. GRB 090929A: Suzaku WAM observation of the prompt emission
  42. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  43. GRB 091003: UVOT-enhanced XRT position
  44. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  45. GRB 091003A: Fermi LAT detection
  46. GRB 090929A, Swift-BAT refined analysis
  47. GRB 090929B, Swift-BAT refined analysis
  48. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  49. Konus-Wind observation of GRB 090929A
  50. Konus-Wind observation of GRB 090929B
  51. GRB 090929B: Gemini-N upper limits
  52. GRB 090929B: Swift/UVOT Observations
  53. Konus-RF observation of GRB 090929A
  54. GRB 090929B: RAPTOR Discovery of Optical Counterpart
  55. Correction: GRB 090929B: Enhanced Swift-XRT position
  56. GRB 090929: Enhanced Swift-XRT position
  57. GRB 090929B: Swift detection of a burst
  58. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  59. Konus-Wind and Konus-RF observations of GRB 090926A
  60. GRB 090927: Zadko Telescope observations
  61. Swift/UVOT observations of GRB 090927
  62. GRB 090927: Swift XRT refined analysis
  63. GRB 090926A: Suzaku WAM observation of the prompt emission
  64. GRB 090927: Enhanced Swift-XRT position
  65. GRB090926B: Swift/UVOT Upper Limits
  66. GRB090926A: Swift/UVOT observations
  67. GRB 090926B: optical object in error circle
  68. GRB 090926B: NOT optical observation
  69. GRB 090926B: Swift XRT 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. GRB 090715B: Skynet/PROMPT Detections
  76. GRB 090916: Swift-XRT upper limit
  77. GRB 090915: GROND upper limits
  78. Short-Duration GRB 090916: Skynet/PROMPT Observations
  79. GRB 090915: SARA detection of afterglow candidate
  80. GRB 090912: optical observation
  81. GRB 090915: Swift/UVOT detection of an optical afterglow candidate
  82. GRB 090902B: Skynet/PROMPT Observations
  83. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  84. GRB 090915 Swift-BAT detection of a burst in ground analysis
  85. GRB 090827: Confirmation of the X-ray afterglow
  86. GRB 090912: Swift/UVOT Upper Limits
  87. GRB 090912 optical upper limit
  88. GRB 090912: Enhanced Swift-XRT position
  89. GRB 090912: Swift detection of a burst
  90. GRB 090823: Swift XRT confirmation of the X-ray afterglow
  91. GRB 090904B: GROND detection of the optical afterglow
  92. GRB 090831A: Suzaku WAM observation of the prompt emission
  93. GRB 090904B: Swift/UVOT Refined Analysis
  94. GRB 090902B: Suzaku WAM observation of the prompt emission
  95. GRB 090829A: Suzaku WAM observation of the prompt emission
  96. GRB 090904A: Enhanced Swift XRT position
  97. GRB 090904B: Swift-BAT refined analysis
  98. GRB 090902B: VLA radio detection
  99. GRB 090904A: Swift-BAT refined analysis
  100. GRB 090904B: Enhanced Swift-XRT position

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