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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"
  1. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  2. GRB050502B: Optical Limits from ANU 1m
  3. Swift Detection of the Bright Burst GRB050502b
  4. GRB 050502: INTEGRAL results
  5. GRB050502: ANU 1m optical Observations
  6. GRB 050502: Confirmed variability of the afterglow candidate +
  7. GRB 050502: PAIRITEL IR Observations
  8. GRB050502 - Correction on the Optical Candidate from the Liverpool
  9. GRB050502 - Optical Candidate from the Liverpool Telescope
  10. GRB 050502 - A long GRB detected with INTEGRAL
  11. GRB 050502: ROTSE-III Detection of Possible Counterpart
  12. Swift-BAT Trigger 115881 is not a real GRB
  13. Swift/BAT possible detection of a weak burst GRB050430
  14. GRB 050401: Rc observation
  15. GRB050416a: Radio Detection
  16. GRB 050422: Swift-UVOT observation
  17. GRB 050422: Swift-BAT refined analysis
  18. GRB 050422: Swift XRT Position
  19. Swift Detection of GRB 050422
  20. GRB 050421: NIR observations
  21. GRB 050416: Optical/NIR observations
  22. GRB 050421: SLOTIS observations
  23. GRB 050421: Further Analysis of IR imaging
  24. GRB050421: Radio Observations
  25. GRB050421: Radio Observations
  26. GRB 050421: Swift-UVOT observation
  27. GRB 050421: IR Observations
  28. GRB 050421: Swift-BAT refined analysis
  29. GRB 050421: ROTSE-III Optical Limits
  30. GRB 050421: NIR observations re-examination
  31. GRB050421
  32. GRB 050421: early Swift XRT analysis results
  33. GRB 050421: NIR observations
  34. GRB050421: P60 Observations
  35. GRB 050421: BOOTES-2 simultaneous optical observations
  36. GRB 050421: Optical observations at the INT
  37. Swift Detection of GRB050421
  38. GRB 050416b: Tentative Swift XRT Position
  39. GRB 050315: potential host galaxy
  40. GRB050326: analysis of the XMM-Newton observation
  41. GRB050418: Null Optical Observations
  42. GRB 050412: Chandra observations
  43. GRB050416A, optical observations
  44. GRB 050418: Swift-BAT refined analysis
  45. Swift-BAT detection of the bright and long GRB 050418
  46. GRB 050416: Mitsume optical observation
  47. GRB 050416 : optical observation at Xinglong observatory
  48. GRB 050416B: optical observations
  49. GRB 050416b: Swift-BAT refined analysis
  50. GRB 050416b: LCO observations
  51. GRB 050416b: LCO observations
  52. GRB050416B: IR observations
  53. GRB 050416: Swift/UVOT refined analysis
  54. Swift-BAT detection of GRB 050416b
  55. IBAS GRB Alert # 2463: not a GRB
  56. GRB050412: Radio Observations
  57. GRB 050416: Swift/UVOT detection of afterglow emission
  58. GRB050416: Refined Swift-XRT analysis
  59. GRB050416: Maidanak optical observations
  60. GRB 050416: Swift-BAT refined analysis
  61. GRB 050416: ART observations
  62. GRB 050416,optical observation
  63. GRB 050416: KAIT observations
  64. GRB050416: P200 NIR Observations
  65. GRB 050416: Swift XRT Position
  66. GRB 050416: Radio observations
  67. Confirmation of OT for GRB050416
  68. GRB050416: P60 Afterglow Candidate
  69. Swift BAT/XRT Detection of GRB 050416
  70. GRB 050412: Subaru observations
  71. GRB 050408: RTT150 optical observations
  72. GRB050408: optical observation
  73. GRB 050412: PROMPT VRcIc Observations
  74. GRB 050408: Kuiper 1.5m observations
  75. GRB 050412: optical limit
  76. GRB 050412: optical observations
  77. GRB 050408: refined XRT analysis, no jet break seen yet
  78. GRB 050412: early Swift XRT analysis results
  79. GRB 050412 : XingLong optical observation
  80. GRB 050412: Swift-BAT refined analysis
  81. GRB 050412: ANU 2.3m observations
  82. GRB 050412: Early Optical/Ultraviolet Observations with
  83. GRB 050412: retraction of UVOT transient report
  84. GRB 050412: UVOT transient not in XRT error circle
  85. GRB 050408: SDSS Field Calibration
  86. GRB 050412: Optical limit
  87. GRB 050412: LCO Optical Observations
  88. GRB 050412: Optical observations
  89. GRB050412: P60 Observations
  90. GRB 050412: Swift XRT Position
  91. GRB050412: optical limit before and during GRB
  92. GRB 050412: LCO optical observations
  93. GRB050412: ROTSE-III Optical Limits
  94. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  95. GRB 050412: IR and Optical observations
  96. GRB 050412: IR Observations
  97. GRB050408: Radio Observations
  98. GRB 050401: Optical limit
  99. GRB 050408: Optical limit
  100. GRB050410: P60 Observations

Advanced

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