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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"

32692 results found.

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

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