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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').
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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.

Advanced Search Examples (click to copy):

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

27408 results found.

  1. GRB 061213: MASTER-VWF-Kislovodsk observations
  2. GRB 061210: Gemini/GMOS Observations
  3. GRB061210: Radio Observations
  4. GRB 061210: MDM Observation
  5. GRB 061210, Swift-BAT refined analysis of the SHB
  6. GRB 061210: Swift-BAT detection of a short burst
  7. Optical Afterglow observations of GRB 061126
  8. GRB061126: update on the Swift-XRT afterglow light curve
  9. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  10. GRB 061202: TORTOREM optical upper limits
  11. GRB061126 : NMSU 1.0m observations
  12. GRB 061202: Swift XRT refined analysis
  13. GRB061202: FRAM early follow-up limit
  14. GRB061202 optical limit by "Pi of the Sky"
  15. Konus-Wind observation of GRB 061201
  16. GRB061202: optical/NIR observations with REM
  17. GRB061202: Swift/UVOT Upper Limits
  18. GRB 061202, Swift-BAT refined analysis
  19. GRB 061202: Swift detection of a burst
  20. GRB 061201: Swift XRT Team refined analysis
  21. GRB 061201: Initial UVOT Observations
  22. GRB 061201, Swift-BAT refined analysis of the SHB
  23. GRB 061201: Swift detection of a short hard burst
  24. GRB 061201: Coincidence with a Galaxy Cluster
  25. GRB 061122: GETS observation
  26. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  27. GRB 061126: Early Super-LOTIS Observations
  28. GRB 061126: optical observation
  29. GRB061126: Optical afterglow observations from MIRO
  30. GRB061126: Optical afterglow observations from MIRO
  31. GRB 061126: Swift-XRT refined analysis
  32. GRB 061126: Swift/UVOT Observations
  33. GRB 061126, Swift-BAT refined analysis
  34. GRB 061126: SARA Observations
  35. GRB 061126: Early Detection of the IR Afterglow
  36. GRB 061126: Faulkes Telescope North Optical Observations
  37. GRB 061126: Swift/UVOT Afterglow Detection
  38. GRB 061126: XRT position
  39. GRB 061126: Swift detection of a burst
  40. GRB 061121: Ep,i - Eiso correlation
  41. GRB061122: Swift/UVOT Optical Observations
  42. GRB 061121: ART detection in Ic
  43. GRB061122: Swift-XRT position
  44. GRB 061121 declared "Burst of Interest" by Swift team
  45. Konus-Wind and Konus-A observations of GRB 061121
  46. Swift-BAT trigger 239987 is not a GRB
  47. GRB 061121: Swift/UVOT Observations
  48. GRB 061121: Swift-XRT Team Refined Analysis
  49. GRB 061121, Swift-BAT refined analysis
  50. GRB061121, optical observation
  51. GRB 061121: Faulkes Telescope North Optical Observation
  52. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  53. GRB 061121: Swift detection of a bright burst with an optical counterpart
  54. GRB 060111B: Swift UVOT Refined Magnitudes
  55. Swift-BAT triggers 238544 and 238546 are not GRBs
  56. GRB 061110B: NIR Observations
  57. Swift/UVOT Upper Limits for GRB061110b
  58. Swift/UVOT Upper Limits for GRB061110a
  59. GRB 061110B, Swift-BAT refined analysis
  60. GRB061110B: Optical observations at Crni Vrh
  61. GRB 061110B: Swift/XRT position
  62. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  63. GRB 061110B: Swift-UVOT Initial Observation
  64. GRB 061110A, Swift-BAT refined analysis
  65. GRB 061110B: TAROT Calern observatory optical observations
  66. GRB 061110B: Swift detection of a burst
  67. GRB 061110: ROTSE-III Optical Limits
  68. GRB 061110: Swift detection of a burst
  69. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  70. GRB 061109: optical observation
  71. GRB 061109: TAROT Calern observatory optical observations
  72. GRB 061109: Swift detection of a possible burst
  73. GRB061028: MAGIC telescope GeV observation
  74. GRB 061027: TAROT La Silla observatory optical observations
  75. GRB 061102: Swift/UVOT Magnitude Upper Limits
  76. GRB 061102, XRT refined analysis
  77. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  78. GRB061102B: Super-LOTIS observations
  79. GRB 061028: Optical R passband observations
  80. GRB 061102B: Swift detection of a possible burst
  81. GRB 061102, Swift-BAT refined analysis
  82. GRB 061102: Swift detection of a burst
  83. GRB 061028: VLA Observation
  84. GRB 061028: MDM Observations
  85. GRB 061028: SARA upper limit
  86. GRB 061028: z band imaging
  87. GRB061028: XRT refined analysis
  88. GRB 061028: Swift/UVOT Observations
  89. GRB 061028, Swift-BAT refined analysis
  90. GRB 061028: TAROT Calern observatory late optical observations
  91. GRB 061028: TAROT Calern observatory optical observations
  92. GRB 061028: Swift detection of a burst
  93. GRB 061027, Swift refined analysis of a possible burst
  94. GRB 061027: Swift detection of a possible burst
  95. GRB061025: Swift XRT refined analysis
  96. GRB061025: Swift/UVOT observations
  97. GRB 061019: MITSuME upper limits
  98. GRB 061025: ROTSE-III Optical Limits
  99. GRB 061021, Swift-BAT Lag analysis
  100. Konus-Wind observation of GRB 061021

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