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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"

43707 results found.

  1. GRB 050504: Swift XRT position
  2. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  3. GRB050502b: Afterglow Confirmation
  4. GRB050502: P200 Observations (Correction)
  5. GRB050502: P200 Observations
  6. GRB 050504 : R band observation at Lulin observatory
  7. Swift UVOT observation of GRB 050504
  8. GRB050504: Faulkes North optical robotic limit
  9. GRB 050502b, V band Observations
  10. GRB050504: P60 Observations
  11. GRB 050504: A long GRB detected with INTEGRAL
  12. GRB (?) 050504: IR Observations, Intriguing Source
  13. GRB050502a: P60 Observations (Correction)
  14. Renewal of SGR 1806-20 activity
  15. GRB 050502a: RBO Observations
  16. GRB 050502A: WSRT Radio Observations
  17. GRB050502A: Optical Observations
  18. GRB050502B Swift-BAT refined analysis
  19. GRB050502B: I band source in XRT error circle
  20. Swift UVOT refined analysis
  21. Retraction of Swift-BAT trigger 116145
  22. GRB 050502b : optical observation at Lulin observatory
  23. GRB 050502b: Swift XRT Position
  24. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  25. GRB050502B: Optical Limits from ANU 1m
  26. Swift Detection of the Bright Burst GRB050502b
  27. GRB 050502: INTEGRAL results
  28. GRB050502: ANU 1m optical Observations
  29. GRB 050502: Confirmed variability of the afterglow candidate +
  30. GRB 050502: PAIRITEL IR Observations
  31. GRB050502 - Correction on the Optical Candidate from the Liverpool
  32. GRB050502 - Optical Candidate from the Liverpool Telescope
  33. GRB 050502 - A long GRB detected with INTEGRAL
  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. Swift Detection of GRB 050422
  43. GRB 050421: NIR observations
  44. GRB 050416: Optical/NIR observations
  45. GRB 050421: SLOTIS observations
  46. GRB 050421: Further Analysis of IR imaging
  47. GRB050421: Radio Observations
  48. GRB050421: Radio Observations
  49. GRB 050421: Swift-UVOT observation
  50. GRB 050421: IR Observations
  51. GRB 050421: Swift-BAT refined analysis
  52. GRB 050421: ROTSE-III Optical Limits
  53. GRB 050421: NIR observations re-examination
  54. GRB050421
  55. GRB 050421: early Swift XRT analysis results
  56. GRB 050421: NIR observations
  57. GRB050421: P60 Observations
  58. GRB 050421: BOOTES-2 simultaneous optical observations
  59. GRB 050421: Optical observations at the INT
  60. Swift Detection of GRB050421
  61. GRB 050416b: Tentative Swift XRT Position
  62. GRB 050315: potential host galaxy
  63. GRB050326: analysis of the XMM-Newton observation
  64. GRB050418: Null Optical Observations
  65. GRB 050412: Chandra observations
  66. GRB050416A, optical observations
  67. GRB 050418: Swift-BAT refined analysis
  68. Swift-BAT detection of the bright and long GRB 050418
  69. GRB 050416: Mitsume optical observation
  70. GRB 050416B: optical observations
  71. GRB 050416b: Swift-BAT refined analysis
  72. GRB 050416b: LCO observations
  73. GRB 050416b: LCO observations
  74. GRB050416B: IR observations
  75. GRB 050416: Swift/UVOT refined analysis
  76. Swift-BAT detection of GRB 050416b
  77. IBAS GRB Alert # 2463: not a GRB
  78. GRB050412: Radio Observations
  79. GRB 050416: Swift/UVOT detection of afterglow emission
  80. GRB050416: Refined Swift-XRT analysis
  81. GRB050416: Maidanak optical observations
  82. GRB 050416: Swift-BAT refined analysis
  83. GRB 050416: ART observations
  84. GRB 050416,optical observation
  85. GRB 050416: KAIT observations
  86. GRB050416: P200 NIR Observations
  87. GRB 050416: Swift XRT Position
  88. GRB 050416: Radio observations
  89. Confirmation of OT for GRB050416
  90. GRB050416: P60 Afterglow Candidate
  91. Swift BAT/XRT Detection of GRB 050416
  92. GRB 050412: Subaru observations
  93. GRB 050408: RTT150 optical observations
  94. GRB050408: optical observation
  95. GRB 050412: PROMPT VRcIc Observations
  96. GRB 050408: Kuiper 1.5m observations
  97. GRB 050412: optical limit
  98. GRB 050412: optical observations
  99. GRB 050408: refined XRT analysis, no jet break seen yet
  100. GRB 050412: early Swift XRT analysis results

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