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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.

Advanced Search Examples (click to copy):

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

28083 results found.

  1. GRB 090531A: Skynet/PROMPT Observations
  2. GRB 090530A: Skynet/DSO Detections
  3. GRB 091010: Enhanced XRT position
  4. GRB 091010 optical upper limits
  5. Detection of a short GRB 090929A by RT-2 Experiment
  6. GRB 091010: GROND afterglow candidate
  7. GRB 091010: Swift/UVOT Upper Limits
  8. GRB 091010: Swift-XRT position
  9. GRB 090910: SuperAGILE Localization of a Long GRB
  10. GRB 090926A: Skynet/PROMPT Observations of Day 6 - 11 Fading
  11. GRB 090518: Skynet/PROMPT Observations
  12. Short-Duration GRB 090621: Skynet/Dolomiti Observations
  13. GRB 090904A: afterglow confirmation
  14. GRB 090812: Skynet/PROMPT and GORT Observations
  15. GRB 091003A: Suzaku WAM observation of the prompt emission
  16. GRB 090926B: Skynet/PROMPT Observations
  17. GRB 091003: WHT ACAM observations
  18. GRB 090929B: Suzaku WAM observation of the prompt emission
  19. GRB 090929A: Suzaku WAM observation of the prompt emission
  20. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  21. GRB 091003: Skynet/DSO Observations
  22. GRB 091003: UVOT-enhanced XRT position
  23. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  24. GRB 091003A: Fermi LAT detection
  25. GRB 090926A: Skynet/PROMPT Observations of Day 4 - 6 Fading Rate
  26. GRB 091003A: Fermi GBM detection
  27. GRB 090926A: Skynet/PROMPT Observations of Post-Peak Fading
  28. GRB 090929A, Swift-BAT refined analysis
  29. GRB 090929B, Swift-BAT refined analysis
  30. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  31. GRB 090929A: Swift-XRT non-detection
  32. Konus-Wind observation of GRB 090929B
  33. GRB 090929B: Swift-XRT refined analysis
  34. GRB 090929B: Gemini-N upper limits
  35. GRB 090929B: Skynet/DSO Observations
  36. GRB 090929B: Swift/UVOT Observations
  37. GRB 090929B: RAPTOR Discovery of Optical Counterpart
  38. GRB 090929A BAT location of the Fermi GBM burst
  39. Correction: GRB 090929B: Enhanced Swift-XRT position
  40. GRB 090929: Enhanced Swift-XRT position
  41. GRB 090929B: Swift detection of a burst
  42. GRB 090929A: Fermi GBM detection
  43. GRB090926A: Swift-XRT refined analysis
  44. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  45. GRB 090927: Zadko Telescope observations
  46. GRB 090927, Swift-BAT refined analysis of the possibly short burst
  47. Swift/UVOT observations of GRB 090927
  48. GRB 090926A: Skynet/PROMPT Continued Observations
  49. GRB 090927: Swift XRT refined analysis
  50. GRB 090926A: Suzaku WAM observation of the prompt emission
  51. GRB 090927: Enhanced Swift-XRT position
  52. GRB090926B: Swift/UVOT Upper Limits
  53. GRB090926A: Swift/UVOT observations
  54. GRB 090927: Swift/UVOT detection of an optical afterglow
  55. GRB 090927: Swift detection of a short burst
  56. GRB 090926B: optical object in error circle
  57. GRB 090926B: MAXI GSC detection
  58. GRB 090926B: NOT optical observation
  59. GRB 090926B: Swift XRT refined analysis
  60. GRB 090926B: Swift-BAT refined analysis
  61. GRB 090926A: Swift/UVOT detection of an optical afterglow
  62. GRB090926A: UVOT-enhanced XRT position
  63. GRB 090926B: Swift detection of a burst
  64. GRB 090926: Fermi LAT detection
  65. GRB 090926: Fermi GBM detection
  66. GRB 090925: Fermi GBM detection
  67. GRB090922A: correction to Fermi location
  68. GRB 090922A: Fermi GBM detection
  69. GRB 090715B: Skynet/PROMPT Detections
  70. GRB 090726: Skynet/GORT Observations
  71. GRB 090916: Swift-XRT upper limit
  72. GRB 090807: Skynet/DSO Observations
  73. GRB 090915: GROND upper limits
  74. Short-Duration GRB 090916: Skynet/PROMPT Observations
  75. GRB 090915: SARA detection of afterglow candidate
  76. GRB 090912: optical observation
  77. GRB 090915: Swift/UVOT detection of an optical afterglow candidate
  78. GRB 090702: Skynet/GORT Observations
  79. GRB 090902B: Skynet/PROMPT Observations
  80. GRB 090916, Swift-BAT refined analysis
  81. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  82. GRB 090915 Swift-BAT detection of a burst in ground analysis
  83. GRB 090827: Confirmation of the X-ray afterglow
  84. GRB 090912: Swift-XRT refined analysis
  85. GRB 090912, Swift-BAT refined analysis
  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 090910: Fermi GBM detection
  91. GRB 090814A: Skynet/DSO & GORT Observations
  92. GRB 090823: Swift XRT confirmation of the X-ray afterglow
  93. GRB 090904B: GROND detection of the optical afterglow
  94. GRB 090831A: Suzaku WAM observation of the prompt emission
  95. GRB 090904B: Swift/UVOT Refined Analysis
  96. GRB 090902B: Suzaku WAM observation of the prompt emission
  97. GRB 090829A: Suzaku WAM observation of the prompt emission
  98. GRB 090904B: Fermi GBM detection
  99. GRB 090904A: Swift-XRT refined analysis
  100. GRB 090904B: Swift XRT Refined Analysis

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