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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"

23415 results found.

  1. GRB 091126B: Fermi GBM detection
  2. GRB 091126: Fermi GBM detection
  3. GRB 091130B: Swift/UVOT Upper Limits
  4. GRB 091130B: Enhanced Swift-XRT position
  5. Swift trigger 377436 (possible GRB 091130A) is not a burst
  6. GRB 091130B: Swift detection of a burst
  7. GRB 091130: Swift detection of a possible burst
  8. GRB 091127: Radio observations
  9. GRB 091128: Fermi GBM detection
  10. Konus-Wind observation of GRB 091127
  11. GRB 091127: TAROT La Silla observatory optical observations
  12. GRB 091127: LABOCA/APEX submm observations
  13. GRB 091127: Further NOT optical observations
  14. GRB 091127: Swift-XRT afterglow detection and analysis
  15. GRB 091127: TAROT La Silla observatory optical decay
  16. GRB 091127: Swift/UVOT observations
  17. GRB 091127: NOT observations
  18. GRB 091127 : GROND observations
  19. GRB 091127: REM NIR afterglow detection
  20. GRB 091127: Swift detection of a burst
  21. IPN Triangulation of GRB091120
  22. GRB 091120: MAXI GSC detection
  23. GRB 091120: Fermi GBM observation
  24. GRB 091117: TNG optical observations
  25. GRB 091117A: Swift/UVOT followup observations
  26. GRB 091117: VLA radio observations
  27. GRB 091117: Swift-XRT observations
  28. GRB 091117: Evidence for Variability of XRT Source #1
  29. GRB091117: Gemini South Observations
  30. GRB 091117: Swift XRT refined analysis
  31. GRB091111: Swift XRT refined analysis
  32. GRB 091031: Fermi LAT detection of a faint burst
  33. GRB 091112: Swift detection of a possible burst
  34. GRB 091111: BOOTES-3 contemporaneous imaging
  35. GRB 091111: BOOTES-3 observations
  36. GRB 091109A: GROND and VLT observations
  37. GRB 091109B: Swift/UVOT Upper Limits
  38. GRB 091109B: Swift-XRT Team refined analysis
  39. GRB 091109b: Magellan Observations
  40. GRB 091109B: Enhanced Swift-XRT position
  41. GRB 091109B: Optical limits from Watcher
  42. GRB 091109B: ROTSE-III Optical Limits
  43. GRB 091109B: Swift detection of a short burst
  44. GRB 091030: Fermi GBM detection
  45. GRB 091109: Swift-XRT refined analysis
  46. GRB 091109: BOOTES-3 observations
  47. GRB 091109: Swift/UVOT observations
  48. GRB 091109: Enhanced Swift-XRT position
  49. GRB091109: REM detection of the NIR afterglow
  50. GRB 091109: Swift detection of a burst with optical afterglow
  51. GRB 091029: Observations from Stardome Observatory
  52. GRB 091104: Swift/UVOT Upper Limits
  53. GRB091102 : MOA optical upper limit
  54. GRB 091104: Enhanced Swift-XRT position
  55. GRB 091104: Swift detection of a burst
  56. GRB 091102: LABOCA/APEX submm observations
  57. Fermi LAT Upper Limits on GRB 091010
  58. GRB 091102 : Faulkes Telescope South Upper Limits
  59. GRB 091102: Swift/UVOT Upper Limits
  60. GRB 091102: GROND Upper Limits
  61. GRB 091102: BOOTES-3 observations
  62. GRB 091102: Swift/XRT localization
  63. GRB 091102: ROTSE-III Optical Limits
  64. GRB 091102: Swift detection of a burst
  65. GRB 091024: optical observations
  66. GRB 091031: Fermi GBM detection
  67. GRB 091024: Fermi LAT upper limits
  68. GRB 091018, SMARTS optical/IR afterglow observations
  69. GRB091029: Swift/UVOT observations
  70. GRB 091029: Swift XRT refined analysis
  71. GRB 091029: BOOTES-3 observations
  72. GRB 091029: Enhanced Swift-XRT position
  73. GRB091024 optical observations
  74. GRB 091029: GROND Detection of the Optical/NIR Afterglow
  75. GRB 091029: Swift detection of a burst with an optical counterpart
  76. GRB 091024: YNAO-GMG observations
  77. GRB 091026: GROND Upper Limits
  78. Radio afterglow detection from GRB 091020
  79. GRB 091026: Swift/UVOT Upper Limits
  80. GRB 091026: Enhanced Swift-XRT position
  81. Konus-Wind and Konus-RF observations of GRB 091024
  82. GRB 091026: Swift detection of a Gamma Ray Burst
  83. GRB091024 Swift/UVOT Upper Limits
  84. GRB 091020: Early TLS Multicolor detections, red afterglow
  85. GRB 091024: Super-LOTIS early observations
  86. GRB091024: VRcIc Afterglow Observations
  87. GRB 091024: Fermi GBM Observations
  88. GRB 091024: Swift-XRT team refined analysis
  89. Swift-BAT trigger 373691 is a galactic bulge transient
  90. GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
  91. GRB 091024: GRAS004 optical observations
  92. GRB 091024: Swift detection of a burst
  93. GRB 091018: Skynet/PROMPT Continued Observations of Fading
  94. GRB091020 Swift/UVOT observations
  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 : Faulkes Telescope South Observations
  99. GRB 091018: BOOTES-3 observations
  100. GRB091018: Swift/UVOT observations

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