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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"

39340 results found.

  1. GRB 050504: A long GRB detected with INTEGRAL
  2. GRB (?) 050504: IR Observations, Intriguing Source
  3. GRB 050502b, Optical observations
  4. GRB050502a: P60 Observations (Correction)
  5. GRB050502a: P60 Observations
  6. Renewal of SGR 1806-20 activity
  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. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  18. Swift Detection of the Bright Burst GRB050502b
  19. GRB 050502: INTEGRAL results
  20. GRB050502: ANU 1m optical Observations
  21. GRB 050502: Confirmed variability of the afterglow candidate +
  22. GRB 050502: PAIRITEL IR Observations
  23. GRB050502 - Correction on the Optical Candidate from the Liverpool
  24. GRB 050502 - A long GRB detected with INTEGRAL
  25. GRB 050502: ROTSE-III Detection of Possible Counterpart
  26. Swift-BAT Trigger 115881 is not a real GRB
  27. Swift/BAT possible detection of a weak burst GRB050430
  28. GRB 050401: Rc observation
  29. GRB050416a: Radio Detection
  30. GRB 050422: Swift-UVOT observation
  31. GRB 050422: Swift-BAT refined analysis
  32. GRB 050422: Swift XRT Position
  33. Swift Detection of GRB 050422
  34. GRB 050421: NIR observations
  35. GRB 050416: Optical/NIR observations
  36. GRB 050421: SLOTIS observations
  37. GRB 050421: Further Analysis of IR imaging
  38. GRB050421: Radio Observations
  39. GRB050421: Radio Observations
  40. GRB 050421: Swift-UVOT observation
  41. GRB 050421: IR Observations
  42. GRB 050421: Swift-BAT refined analysis
  43. GRB 050421: ROTSE-III Optical Limits
  44. GRB 050421: NIR observations re-examination
  45. GRB 050421: early Swift XRT analysis results
  46. GRB 050421: NIR observations
  47. GRB050421: P60 Observations
  48. GRB 050421: BOOTES-2 simultaneous optical observations
  49. GRB 050421: Optical observations at the INT
  50. Swift Detection of GRB050421
  51. GRB 050416b: Tentative Swift XRT Position
  52. GRB 050315: potential host galaxy
  53. GRB 050412: Chandra observations
  54. GRB050416A, optical observations
  55. GRB 050418: Swift-BAT refined analysis
  56. Swift-BAT detection of the bright and long GRB 050418
  57. GRB 050416: Mitsume optical observation
  58. GRB 050416 : optical observation at Xinglong observatory
  59. GRB 050416B: optical observations
  60. GRB 050416b: Swift-BAT refined analysis
  61. GRB 050416b: LCO observations
  62. GRB 050416b: LCO observations
  63. GRB050416B: IR observations
  64. GRB 050416: Swift/UVOT refined analysis
  65. Swift-BAT detection of GRB 050416b
  66. IBAS GRB Alert # 2463: not a GRB
  67. GRB050412: Radio Observations
  68. GRB 050416: Swift/UVOT detection of afterglow emission
  69. GRB 050416: Swift-BAT refined analysis
  70. GRB 050416: ART observations
  71. GRB 050416,optical observation
  72. GRB 050416: KAIT observations
  73. GRB050416: P200 NIR Observations
  74. GRB 050416: Swift XRT Position
  75. GRB 050416: Radio observations
  76. Confirmation of OT for GRB050416
  77. GRB050416: P60 Afterglow Candidate
  78. Swift BAT/XRT Detection of GRB 050416
  79. GRB 050412: Subaru observations
  80. GRB 050408: RTT150 optical observations
  81. GRB 050412: PROMPT VRcIc Observations
  82. GRB 050408: Kuiper 1.5m observations
  83. GRB 050412: optical limit
  84. GRB 050412: optical observations
  85. GRB 050408: refined XRT analysis, no jet break seen yet
  86. GRB 050412: early Swift XRT analysis results
  87. GRB 050412 : XingLong optical observation
  88. GRB 050412: Swift-BAT refined analysis
  89. GRB 050412: ANU 2.3m observations
  90. GRB 050412: Early Optical/Ultraviolet Observations with
  91. GRB 050412: retraction of UVOT transient report
  92. GRB 050412: UVOT transient not in XRT error circle
  93. GRB 050408: SDSS Field Calibration
  94. GRB 050412: Optical limit
  95. GRB 050412: LCO Optical Observations
  96. GRB 050412: Optical observations
  97. GRB050412: P60 Observations
  98. GRB 050412: Swift XRT Position
  99. GRB050412: optical limit before and during GRB
  100. GRB 050412: LCO optical observations

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