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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').
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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"

28300 results found.

  1. GRB 091127: Further NOT optical observations
  2. GRB 091127: Fermi GBM detection
  3. GRB 091127: Swift-XRT afterglow detection and analysis
  4. GRB 091127: TAROT La Silla observatory optical decay
  5. GRB 091127: Swift/UVOT observations
  6. GRB 091127: Swift-BAT refined analysis
  7. GRB 091127: NOT observations
  8. GRB 091127 : GROND observations
  9. GRB 091127: REM NIR afterglow detection
  10. GRB 091127: Swift/UVOT Detection of an Optical Afterglow
  11. GRB 091127: Swift detection of a burst
  12. GRB 091120: Fermi GBM observation
  13. GRB 091117A: Suzaku WAM observation of the prompt emission
  14. GRB 091117: TNG optical observations
  15. GRB 091117A: Swift/UVOT followup observations
  16. GRB 091117: VLA radio observations
  17. GRB 091117: Swift-XRT observations
  18. GRB 091117 BAT refined analysis
  19. GRB 091117: Evidence for Variability of XRT Source #1
  20. GRB091117: Gemini South Observations
  21. GRB 091117: Swift XRT refined analysis
  22. GRB 091112: Suzaku WAM observation of the prompt emission
  23. GRB 091102A: Suzaku WAM observation of the prompt emission
  24. GRB 091109B: Suzaku WAM observation of the prompt emission
  25. GRB091111: Swift XRT refined analysis
  26. GRB 091112: Swift-BAT refined analysis
  27. GRB 091031: Fermi LAT detection of a faint burst
  28. GRB 091111: BOOTES-3 contemporaneous imaging
  29. GRB 091111: BOOTES-3 observations
  30. GRB 091109A: GROND and VLT observations
  31. GRB 091109B: Swift/UVOT Upper Limits
  32. GRB 091109B: Swift-XRT Team refined analysis
  33. GRB 091109B: Swift-BAT refined analysis
  34. GRB 091109B: Enhanced Swift-XRT position
  35. GRB 091109B: Optical limits from Watcher
  36. GRB 091109B: ROTSE-III Optical Limits
  37. GRB 091109B: Swift detection of a short burst
  38. GRB 091030: Fermi GBM detection
  39. GRB 091109: Swift-XRT refined analysis
  40. GRB 091109: BOOTES-3 observations
  41. GRB 091109: Swift/UVOT observations
  42. GRB 091109: Faulkes Telescope South observations
  43. GRB 091109: Swift-BAT refined analysis
  44. GRB 091109: Enhanced Swift-XRT position
  45. GRB091109: REM detection of the NIR afterglow
  46. GRB 091109: Swift detection of a burst with optical afterglow
  47. GRB 091029: Observations from Stardome Observatory
  48. GRB 091104: Swift-BAT refined analysis
  49. GRB 091104: Swift XRT Refined Analysis
  50. GRB 091104: Swift/UVOT Upper Limits
  51. GRB 091104: Enhanced Swift-XRT position
  52. GRB 091104: Swift detection of a burst
  53. GRB 091102: LABOCA/APEX submm observations
  54. Fermi LAT Upper Limits on GRB 091010
  55. GRB 091102 : Faulkes Telescope South Upper Limits
  56. GRB 091102: Swift-XRT refined analysis
  57. GRB 091102: Swift/UVOT Upper Limits
  58. GRB 091102: GROND Upper Limits
  59. GRB 091102: BOOTES-3 observations
  60. GRB 091102: Swift-BAT refined analysis
  61. GRB 091102: Swift/XRT localization
  62. GRB 091024: optical observations
  63. GRB 091031: Fermi GBM detection
  64. GRB 091024: Fermi LAT upper limits
  65. GRB 091018, SMARTS optical/IR afterglow observations
  66. GRB 090920: Skynet/DSO Detection
  67. GRB091029: Swift/UVOT observations
  68. GRB 091029: Swift XRT refined analysis
  69. GRB 091029: Swift-BAT refined analysis
  70. GRB 091029: Enhanced Swift-XRT position
  71. GRB091024 optical observations
  72. GRB 091029: GROND Detection of the Optical/NIR Afterglow
  73. GRB 091029: Swift detection of a burst with an optical counterpart
  74. GRB 091020: Fermi GBM observation
  75. GRB 091026: Suzaku WAM observation of the prompt emission
  76. GRB 091026: GROND Upper Limits
  77. GRB 091026: Swift-BAT refined analysis
  78. Radio afterglow detection from GRB 091020
  79. GRB 091026: Swift/UVOT Upper Limits
  80. GRB 091026: Swift-XRT refined analysis
  81. GRB 091026: Enhanced Swift-XRT position
  82. Konus-Wind and Konus-RF observations of GRB 091024
  83. GRB 091026: Swift detection of a Gamma Ray Burst
  84. GRB091024 Swift/UVOT Upper Limits
  85. GRB 091024: Super-LOTIS early observations
  86. GRB 091024: Swift-BAT refined analysis
  87. GRB 091024: Fermi GBM Observations
  88. GRB 091024: Swift-XRT team refined analysis
  89. GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
  90. GRB 091024: GRAS004 optical observations
  91. GRB 091020: Swift-XRT refined analysis
  92. GRB 091018: Swift XRT refined analysis
  93. GRB091020 Swift/UVOT observations
  94. GRB 091020, Swift-BAT refined analysis
  95. GRB 091020: Enhanced Swift-XRT position
  96. GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
  97. GRB 091020: Swift detection of a burst with an optical afterglow
  98. GRB 091018: Skynet/PROMPT Observations of Fading
  99. Konus-RF observation of GRB 091018
  100. GRB 091018 : Faulkes Telescope South Observations

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