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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"

19615 results found.

  1. GRB091026 : IRSF NIR upper limit
  2. GRB091102 : MOA optical upper limit
  3. GRB 091104: Enhanced Swift-XRT position
  4. GRB 091104: Swift detection of a burst
  5. GRB 091102 : Faulkes Telescope South Upper Limits
  6. GRB 091102A: Fermi GBM observation
  7. GRB 091102: Swift-XRT refined analysis
  8. GRB 091102: Swift/UVOT Upper Limits
  9. GRB 091102: GROND Upper Limits
  10. GRB 091102: Swift-BAT refined analysis
  11. GRB 091102: Swift/XRT localization
  12. GRB 091102: ROTSE-III Optical Limits
  13. GRB 091102: Swift/UVOT Finding Chart Observation
  14. GRB 091102: Swift detection of a burst
  15. GRB 091024: optical observations
  16. GRB 091024: Fermi LAT upper limits
  17. GRB 090920: Skynet/DSO Detection
  18. GRB091029: Swift/UVOT observations
  19. GRB 091029: Swift XRT refined analysis
  20. GRB 091029: Swift-BAT refined analysis
  21. GRB 091029: Enhanced Swift-XRT position
  22. GRB 091029: Skynet/PROMPT Observations of Peak and Fading
  23. GRB 091029: GROND Detection of the Optical/NIR Afterglow
  24. GRB 091029: Swift detection of a burst with an optical counterpart
  25. A mistake in testing a new function in Swift
  26. GRB 091020: Fermi GBM observation
  27. GRB 091026: Suzaku WAM observation of the prompt emission
  28. GRB 091026: GROND Upper Limits
  29. GRB 091020: Late TLS detection
  30. GRB 091026: Swift-BAT refined analysis
  31. Radio afterglow detection from GRB 091020
  32. GRB 091026: Swift/UVOT Upper Limits
  33. GRB 091024: Burst was outside the Swift-BAT FOV after T0(BAT)+460sec
  34. GRB 091026: Swift-XRT refined analysis
  35. GRB 091026: Enhanced Swift-XRT position
  36. Konus-Wind and Konus-RF observations of GRB 091024
  37. GRB 091026: Updated Swift-XRT position
  38. GRB 091026: Swift detection of a Gamma Ray Burst
  39. Swift-BAT Triggers 373776-373778 are not real
  40. GRB091024 Swift/UVOT Upper Limits
  41. GRB 091024: TLS Upper Limit
  42. GRB 091020: Early TLS Multicolor detections, red afterglow
  43. GRB 091024: KAIT optical afterglow observations
  44. GRB 091024: Swift-BAT refined analysis
  45. Swift-BAT Triggers 373679-373684 are not real
  46. GRB 091024: Fermi GBM Observations
  47. GRB 091024: Swift-XRT team refined analysis
  48. Swift-BAT trigger 373691 is a galactic bulge transient
  49. GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
  50. GRB 091024: Faulkes Telescope North Afterglow Candidate
  51. GRB 091024: Swift detection of a burst
  52. GRB 091020: Swift-XRT refined analysis
  53. GRB 091018: Swift XRT refined analysis
  54. GRB091020 Swift/UVOT observations
  55. GRB 091020, Swift-BAT refined analysis
  56. GRB 091020: Enhanced Swift-XRT position
  57. GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
  58. GRB 091020: Swift detection of a burst with an optical afterglow
  59. GRB 091018: Skynet/PROMPT Observations of Fading
  60. Konus-RF observation of GRB 091018
  61. GRB 091018 : Faulkes Telescope South Observations
  62. GRB091018: Swift/UVOT observations
  63. GRB 091018: Swift-BAT refined analysis
  64. GRB 091018: Enhanced Swift-XRT position
  65. GRB 091018: ROTSE-III Detection of Optical Counterpart
  66. GRB 091018: Swift detection of a burst with optical afterglow
  67. GRB 090726 R band observations
  68. GRB 091010: Swift-XRT refined analysis
  69. Radio observation of GRB090927 with ATCA
  70. GRB 091010: Fermi GBM observation
  71. GRB 090531A: Skynet/PROMPT Observations
  72. GRB 090530A: Skynet/DSO Detections
  73. GRB 091010: Enhanced XRT position
  74. GRB 091010: GROND afterglow candidate
  75. GRB 091010: Swift/UVOT Upper Limits
  76. GRB 091010: Swift-XRT position
  77. GRB 090518: Skynet/PROMPT Observations
  78. Short-Duration GRB 090621: Skynet/Dolomiti Observations
  79. GRB 090812: Skynet/PROMPT and GORT Observations
  80. GRB 091003: Lick observations and possible SDSS host galaxy
  81. GRB 090926B: Skynet/PROMPT Observations
  82. GRB 090929B: Suzaku WAM observation of the prompt emission
  83. GRB 091003: Swift-XRT confirmation of fading afterglow
  84. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  85. GRB 091003: UVOT-enhanced XRT position
  86. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  87. GRB 091003: Swift XRT analysis
  88. GRB 091003A: Fermi LAT detection
  89. GRB 090929A: Swift/UVOT Observations
  90. GRB 090929A, Swift-BAT refined analysis
  91. GRB 090929B, Swift-BAT refined analysis
  92. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  93. GRB 090929A: Swift-XRT non-detection
  94. Konus-Wind observation of GRB 090929A
  95. Konus-Wind observation of GRB 090929B
  96. GRB 090927: Fermi GBM observation
  97. GRB 090929B: Swift-XRT refined analysis
  98. GRB 090929B: Skynet/DSO Observations
  99. GRB 090929B: Swift/UVOT Observations
  100. Konus-RF observation of GRB 090929A

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