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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"

32706 results found.

  1. GRB 050505: Swift XRT Position
  2. GRB050505 Swift-BAT refined analysis
  3. GRB 050502a: Optical Observations
  4. GRB 050416b:Swift XRT afterglow upper limits
  5. GRB 050416b:Swift XRT afterglow upper limits
  6. Swift-BAT detection of GRB050505
  7. GRB 050504: Swift XRT position
  8. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  9. GRB050502b: Afterglow Confirmation
  10. GRB050502: P200 Observations (Correction)
  11. GRB050502: P200 Observations
  12. GRB 050504 : R band observation at Lulin observatory
  13. Swift UVOT observation of GRB 050504
  14. GRB 050504, R band Observations
  15. GRB050504: P60 Observations
  16. GRB 050502b, Optical observations
  17. GRB050502a: P60 Observations (Correction)
  18. GRB050502a: P60 Observations
  19. GRB 050502a: RBO Observations
  20. GRB 050502A: WSRT Radio Observations
  21. GRB050502A: Optical Observations
  22. GRB050502B Swift-BAT refined analysis
  23. GRB050502B: I band source in XRT error circle
  24. Swift UVOT refined analysis
  25. Retraction of Swift-BAT trigger 116145
  26. GRB 050502a : R band observation at Lulin observatory
  27. GRB 050502b : optical observation at Lulin observatory
  28. GRB 050502b: Swift XRT Position
  29. GRB050502B: Optical Limits from ANU 1m
  30. GRB 050502: INTEGRAL results
  31. GRB050502: ANU 1m optical Observations
  32. GRB 050502: Confirmed variability of the afterglow candidate +
  33. GRB 050502: PAIRITEL IR Observations
  34. GRB 050502: ROTSE-III Detection of Possible Counterpart
  35. Swift-BAT Trigger 115881 is not a real GRB
  36. Swift/BAT possible detection of a weak burst GRB050430
  37. GRB 050401: Rc observation
  38. GRB050416a: Radio Detection
  39. GRB 050422: Swift-UVOT observation
  40. GRB 050422: Swift-BAT refined analysis
  41. GRB 050422: Swift XRT Position
  42. GRB 050421: NIR observations
  43. GRB 050416: Optical/NIR observations
  44. GRB 050421: SLOTIS observations
  45. GRB 050421: Further Analysis of IR imaging
  46. GRB050421: Radio Observations
  47. GRB050421: Radio Observations
  48. GRB 050421: Swift-UVOT observation
  49. GRB 050421: IR Observations
  50. GRB 050421: Swift-BAT refined analysis
  51. GRB 050421: ROTSE-III Optical Limits
  52. GRB 050421: NIR observations re-examination
  53. GRB050421
  54. GRB 050421: early Swift XRT analysis results
  55. GRB 050421: NIR observations
  56. GRB050421: P60 Observations
  57. GRB 050421: BOOTES-2 simultaneous optical observations
  58. GRB 050421: Optical observations at the INT
  59. Swift Detection of GRB050421
  60. GRB 050416b: Tentative Swift XRT Position
  61. GRB 050315: potential host galaxy
  62. GRB050418: Null Optical Observations
  63. GRB 050412: Chandra observations
  64. GRB050416A, optical observations
  65. GRB 050418: Swift-BAT refined analysis
  66. GRB 050416: Mitsume optical observation
  67. GRB 050416 : optical observation at Xinglong observatory
  68. GRB 050416B: optical observations
  69. GRB 050416b: Swift-BAT refined analysis
  70. GRB 050416b: LCO observations
  71. GRB 050416b: LCO observations
  72. GRB050416B: IR observations
  73. GRB 050416: Swift/UVOT refined analysis
  74. GRB050412: Radio Observations
  75. GRB 050416: Swift/UVOT detection of afterglow emission
  76. GRB050416: Refined Swift-XRT analysis
  77. GRB 050416: Swift-BAT refined analysis
  78. GRB 050416: ART observations
  79. GRB 050416: KAIT observations
  80. GRB050416: P200 NIR Observations
  81. GRB 050416: Swift XRT Position
  82. GRB 050416: Radio observations
  83. GRB 050412: Subaru observations
  84. GRB 050408: RTT150 optical observations
  85. GRB050408: optical observation
  86. GRB 050412: PROMPT VRcIc Observations
  87. GRB 050408: Kuiper 1.5m observations
  88. GRB 050412: optical limit
  89. GRB 050412: optical observations
  90. GRB 050408: refined XRT analysis, no jet break seen yet
  91. GRB 050412: early Swift XRT analysis results
  92. GRB 050412 : XingLong optical observation
  93. GRB 050412: Swift-BAT refined analysis
  94. GRB 050412: ANU 2.3m observations
  95. GRB 050412: Early Optical/Ultraviolet Observations with
  96. GRB 050412: retraction of UVOT transient report
  97. GRB 050412: Optical limit
  98. GRB 050412: LCO Optical Observations
  99. GRB 050412: Optical observations
  100. GRB050412: P60 Observations

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