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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"

32494 results found.

  1. Swift UVOT observation of GRB 050504
  2. GRB 050504, R band Observations
  3. GRB050504: P60 Observations
  4. GRB 050502b, Optical observations
  5. GRB050502a: P60 Observations (Correction)
  6. GRB050502a: P60 Observations
  7. GRB 050502a: RBO Observations
  8. GRB 050502A: WSRT Radio Observations
  9. GRB050502A: Optical Observations
  10. GRB050502B Swift-BAT refined analysis
  11. GRB050502B: I band source in XRT error circle
  12. Swift UVOT refined analysis
  13. Retraction of Swift-BAT trigger 116145
  14. GRB 050502a : R band observation at Lulin observatory
  15. GRB 050502b : optical observation at Lulin observatory
  16. GRB 050502b: Swift XRT Position
  17. GRB050502B: Optical Limits from ANU 1m
  18. GRB 050502: INTEGRAL results
  19. GRB050502: ANU 1m optical Observations
  20. GRB 050502: Confirmed variability of the afterglow candidate +
  21. GRB 050502: PAIRITEL IR Observations
  22. GRB 050502: ROTSE-III Detection of Possible Counterpart
  23. Swift-BAT Trigger 115881 is not a real GRB
  24. Swift/BAT possible detection of a weak burst GRB050430
  25. GRB 050401: Rc observation
  26. GRB050416a: Radio Detection
  27. GRB 050422: Swift-UVOT observation
  28. GRB 050422: Swift-BAT refined analysis
  29. GRB 050422: Swift XRT Position
  30. GRB 050421: NIR observations
  31. GRB 050416: Optical/NIR observations
  32. GRB 050421: SLOTIS observations
  33. GRB 050421: Further Analysis of IR imaging
  34. GRB050421: Radio Observations
  35. GRB050421: Radio Observations
  36. GRB 050421: Swift-UVOT observation
  37. GRB 050421: IR Observations
  38. GRB 050421: Swift-BAT refined analysis
  39. GRB 050421: ROTSE-III Optical Limits
  40. GRB 050421: NIR observations re-examination
  41. GRB050421
  42. GRB 050421: early Swift XRT analysis results
  43. GRB 050421: NIR observations
  44. GRB050421: P60 Observations
  45. GRB 050421: BOOTES-2 simultaneous optical observations
  46. GRB 050421: Optical observations at the INT
  47. Swift Detection of GRB050421
  48. GRB 050416b: Tentative Swift XRT Position
  49. GRB 050315: potential host galaxy
  50. GRB050418: Null Optical Observations
  51. GRB 050412: Chandra observations
  52. GRB050416A, optical observations
  53. GRB 050418: Swift-BAT refined analysis
  54. GRB 050416: Mitsume optical observation
  55. GRB 050416 : optical observation at Xinglong observatory
  56. GRB 050416B: optical observations
  57. GRB 050416b: Swift-BAT refined analysis
  58. GRB 050416b: LCO observations
  59. GRB 050416b: LCO observations
  60. GRB050416B: IR observations
  61. GRB 050416: Swift/UVOT refined analysis
  62. GRB050412: Radio Observations
  63. GRB 050416: Swift/UVOT detection of afterglow emission
  64. GRB050416: Refined Swift-XRT analysis
  65. GRB 050416: Swift-BAT refined analysis
  66. GRB 050416: ART observations
  67. GRB 050416: KAIT observations
  68. GRB050416: P200 NIR Observations
  69. GRB 050416: Swift XRT Position
  70. GRB 050416: Radio observations
  71. GRB 050412: Subaru observations
  72. GRB 050408: RTT150 optical observations
  73. GRB050408: optical observation
  74. GRB 050412: PROMPT VRcIc Observations
  75. GRB 050408: Kuiper 1.5m observations
  76. GRB 050412: optical limit
  77. GRB 050412: optical observations
  78. GRB 050408: refined XRT analysis, no jet break seen yet
  79. GRB 050412: early Swift XRT analysis results
  80. GRB 050412 : XingLong optical observation
  81. GRB 050412: Swift-BAT refined analysis
  82. GRB 050412: ANU 2.3m observations
  83. GRB 050412: Early Optical/Ultraviolet Observations with
  84. GRB 050412: retraction of UVOT transient report
  85. GRB 050412: Optical limit
  86. GRB 050412: LCO Optical Observations
  87. GRB 050412: Optical observations
  88. GRB050412: P60 Observations
  89. GRB 050412: Swift XRT Position
  90. GRB050412: optical limit before and during GRB
  91. GRB 050412: LCO optical observations
  92. GRB050412: ROTSE-III Optical Limits
  93. GRB050408: Radio Observations
  94. GRB 050401: Optical limit
  95. GRB 050408: Optical limit
  96. GRB050410: P60 Observations
  97. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  98. GRB 050410, optical observations
  99. GRB 050408: PROMPT VRcIc Observations
  100. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT

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