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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"

42843 results found.

  1. GRB 050502a: Optical Observations
  2. GRB 050416b:Swift XRT afterglow upper limits
  3. GRB 050416b:Swift XRT afterglow upper limits
  4. Swift-BAT detection of GRB050505
  5. GRB 050504: Swift XRT position
  6. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  7. GRB050502b: Afterglow Confirmation
  8. GRB050502: P200 Observations (Correction)
  9. GRB050502: P200 Observations
  10. Swift UVOT observation of GRB 050504
  11. GRB050504: Faulkes North optical robotic limit
  12. GRB 050502b, V band Observations
  13. GRB050504: P60 Observations
  14. GRB 050504: A long GRB detected with INTEGRAL
  15. GRB (?) 050504: IR Observations, Intriguing Source
  16. GRB 050502b, Optical observations
  17. GRB050502a: P60 Observations (Correction)
  18. Renewal of SGR 1806-20 activity
  19. GRB 050502A: WSRT Radio Observations
  20. GRB050502A: Optical Observations
  21. GRB050502B Swift-BAT refined analysis
  22. GRB050502B: I band source in XRT error circle
  23. Swift UVOT refined analysis
  24. Retraction of Swift-BAT trigger 116145
  25. GRB 050502b: Swift XRT Position
  26. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  27. GRB050502B: Optical Limits from ANU 1m
  28. Swift Detection of the Bright Burst GRB050502b
  29. GRB 050502: INTEGRAL results
  30. GRB050502: ANU 1m optical Observations
  31. GRB 050502: Confirmed variability of the afterglow candidate +
  32. GRB 050502: PAIRITEL IR Observations
  33. GRB050502 - Correction on the Optical Candidate from the Liverpool
  34. GRB050502 - Optical Candidate from the Liverpool Telescope
  35. GRB 050502 - A long GRB detected with INTEGRAL
  36. GRB 050502: ROTSE-III Detection of Possible Counterpart
  37. Swift-BAT Trigger 115881 is not a real GRB
  38. Swift/BAT possible detection of a weak burst GRB050430
  39. GRB 050401: Rc observation
  40. GRB050416a: Radio Detection
  41. GRB 050422: Swift-UVOT observation
  42. GRB 050422: Swift-BAT refined analysis
  43. GRB 050422: Swift XRT Position
  44. Swift Detection of GRB 050422
  45. GRB 050421: NIR observations
  46. GRB 050416: Optical/NIR observations
  47. GRB 050421: SLOTIS observations
  48. GRB 050421: Further Analysis of IR imaging
  49. GRB050421: Radio Observations
  50. GRB050421: Radio Observations
  51. GRB 050421: Swift-UVOT observation
  52. GRB 050421: IR Observations
  53. GRB 050421: Swift-BAT refined analysis
  54. GRB 050421: ROTSE-III Optical Limits
  55. GRB 050421: NIR observations re-examination
  56. GRB050421
  57. GRB 050421: early Swift XRT analysis results
  58. GRB 050421: NIR observations
  59. GRB050421: P60 Observations
  60. GRB 050421: BOOTES-2 simultaneous optical observations
  61. GRB 050421: Optical observations at the INT
  62. Swift Detection of GRB050421
  63. GRB 050416b: Tentative Swift XRT Position
  64. GRB 050315: potential host galaxy
  65. GRB050326: analysis of the XMM-Newton observation
  66. GRB050418: Null Optical Observations
  67. GRB 050412: Chandra observations
  68. GRB050416A, optical observations
  69. GRB 050418: Swift-BAT refined analysis
  70. Swift-BAT detection of the bright and long GRB 050418
  71. GRB 050416: Mitsume optical observation
  72. GRB 050416B: optical observations
  73. GRB 050416b: Swift-BAT refined analysis
  74. GRB 050416b: LCO observations
  75. GRB 050416b: LCO observations
  76. GRB050416B: IR observations
  77. GRB 050416: Swift/UVOT refined analysis
  78. Swift-BAT detection of GRB 050416b
  79. IBAS GRB Alert # 2463: not a GRB
  80. GRB050412: Radio Observations
  81. GRB 050416: Swift/UVOT detection of afterglow emission
  82. GRB050416: Refined Swift-XRT analysis
  83. GRB050416: Maidanak optical observations
  84. GRB 050416: Swift-BAT refined analysis
  85. GRB 050416: ART observations
  86. GRB 050416,optical observation
  87. GRB 050416: KAIT observations
  88. GRB 050416: Swift XRT Position
  89. GRB 050416: Radio observations
  90. Confirmation of OT for GRB050416
  91. GRB050416: P60 Afterglow Candidate
  92. Swift BAT/XRT Detection of GRB 050416
  93. GRB 050412: Subaru observations
  94. GRB 050408: RTT150 optical observations
  95. GRB050408: optical observation
  96. GRB 050412: PROMPT VRcIc Observations
  97. GRB 050408: Kuiper 1.5m observations
  98. GRB 050412: optical limit
  99. GRB 050412: optical observations
  100. GRB 050408: refined XRT analysis, no jet break seen yet

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