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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"

45692 results found.

  1. GRB050502a: P60 Observations
  2. Renewal of SGR 1806-20 activity
  3. GRB 050502a: RBO Observations
  4. GRB 050502A: WSRT Radio Observations
  5. GRB050502A: Optical Observations
  6. GRB050502B Swift-BAT refined analysis
  7. GRB050502B: I band source in XRT error circle
  8. Swift UVOT refined analysis
  9. Retraction of Swift-BAT trigger 116145
  10. GRB 050502a : R band observation at Lulin observatory
  11. GRB 050502b : optical observation at Lulin observatory
  12. GRB 050502b: Swift XRT Position
  13. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  14. GRB050502B: Optical Limits from ANU 1m
  15. Swift Detection of the Bright Burst GRB050502b
  16. GRB 050502: INTEGRAL results
  17. GRB050502: ANU 1m optical Observations
  18. GRB 050502: Confirmed variability of the afterglow candidate +
  19. GRB 050502: PAIRITEL IR Observations
  20. GRB050502 - Correction on the Optical Candidate from the Liverpool
  21. GRB050502 - Optical Candidate from the Liverpool Telescope
  22. GRB 050502 - A long GRB detected with INTEGRAL
  23. GRB 050502: ROTSE-III Detection of Possible Counterpart
  24. Swift-BAT Trigger 115881 is not a real GRB
  25. Swift/BAT possible detection of a weak burst GRB050430
  26. GRB 050401: Rc observation
  27. GRB050416a: Radio Detection
  28. GRB 050422: Swift-UVOT observation
  29. GRB 050422: Swift-BAT refined analysis
  30. GRB 050422: Swift XRT Position
  31. Swift Detection of GRB 050422
  32. GRB 050421: NIR observations
  33. GRB 050416: Optical/NIR observations
  34. GRB 050421: SLOTIS observations
  35. GRB 050421: Further Analysis of IR imaging
  36. GRB050421: Radio Observations
  37. GRB050421: Radio Observations
  38. GRB 050421: Swift-UVOT observation
  39. GRB 050421: IR Observations
  40. GRB 050421: Swift-BAT refined analysis
  41. GRB 050421: ROTSE-III Optical Limits
  42. GRB 050421: NIR observations re-examination
  43. GRB050421
  44. GRB 050421: early Swift XRT analysis results
  45. GRB 050421: NIR observations
  46. GRB050421: P60 Observations
  47. GRB 050421: BOOTES-2 simultaneous optical observations
  48. GRB 050421: Optical observations at the INT
  49. Swift Detection of GRB050421
  50. GRB 050416b: Tentative Swift XRT Position
  51. GRB 050315: potential host galaxy
  52. GRB050326: analysis of the XMM-Newton observation
  53. GRB050418: Null Optical Observations
  54. GRB 050412: Chandra observations
  55. GRB050416A, optical observations
  56. GRB 050418: Swift-BAT refined analysis
  57. Swift-BAT detection of the bright and long GRB 050418
  58. GRB 050416: Mitsume optical observation
  59. GRB 050416 : optical observation at Xinglong observatory
  60. GRB 050416B: optical observations
  61. GRB 050416b: Swift-BAT refined analysis
  62. GRB 050416b: LCO observations
  63. GRB 050416b: LCO observations
  64. GRB050416B: IR observations
  65. GRB 050416: Swift/UVOT refined analysis
  66. Swift-BAT detection of GRB 050416b
  67. IBAS GRB Alert # 2463: not a GRB
  68. GRB050412: Radio Observations
  69. GRB 050416: Swift/UVOT detection of afterglow emission
  70. GRB050416: Refined Swift-XRT analysis
  71. GRB050416: Maidanak optical observations
  72. GRB 050416: Swift-BAT refined analysis
  73. GRB 050416: ART observations
  74. GRB 050416,optical observation
  75. GRB 050416: KAIT observations
  76. GRB050416: P200 NIR Observations
  77. GRB 050416: Swift XRT Position
  78. GRB 050416: Radio observations
  79. Confirmation of OT for GRB050416
  80. GRB050416: P60 Afterglow Candidate
  81. Swift BAT/XRT Detection of GRB 050416
  82. GRB 050412: Subaru observations
  83. GRB 050408: RTT150 optical observations
  84. GRB050408: optical observation
  85. GRB 050412: PROMPT VRcIc Observations
  86. GRB 050408: Kuiper 1.5m observations
  87. GRB 050412: optical limit
  88. GRB 050412: optical observations
  89. GRB 050408: refined XRT analysis, no jet break seen yet
  90. GRB 050412: early Swift XRT analysis results
  91. GRB 050412 : XingLong optical observation
  92. GRB 050412: Swift-BAT refined analysis
  93. GRB 050412: ANU 2.3m observations
  94. GRB 050412: Early Optical/Ultraviolet Observations with
  95. GRB 050412: retraction of UVOT transient report
  96. GRB 050412: UVOT transient not in XRT error circle
  97. GRB 050408: SDSS Field Calibration
  98. GRB 050412: Optical limit
  99. GRB 050412: LCO Optical Observations
  100. GRB 050412: Optical observations

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