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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"

28113 results found.

  1. Swift-BAT detection of GRB 050507
  2. GRB 050505: Keck I-band Magnitude
  3. GRB 050505: early time observations
  4. GRB 050502a: Swift XRT Upper Limit
  5. GRB 050505: Further Swift UVOT observations.
  6. GRB050505: AAVSO observations
  7. GRB050416A : 1 GHz limit from GMRT
  8. GRB 050505 UVOT
  9. GRB050505: Optical Afterglow Candidate
  10. GRB 050505: Swift XRT Position
  11. GRB 050502a: Optical Observations
  12. GRB 050416b:Swift XRT afterglow upper limits
  13. GRB 050416b:Swift XRT afterglow upper limits
  14. Swift-BAT detection of GRB050505
  15. GRB 050504: Swift XRT position
  16. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  17. GRB050502b: Afterglow Confirmation
  18. GRB050502: P200 Observations (Correction)
  19. GRB050502: P200 Observations
  20. GRB050502a: P60 Observations (Correction)
  21. GRB050502a: P60 Observations
  22. GRB 050502a: RBO Observations
  23. GRB 050502A: WSRT Radio Observations
  24. GRB050502A: Optical Observations
  25. GRB050502B Swift-BAT refined analysis
  26. GRB050502B: I band source in XRT error circle
  27. Swift UVOT refined analysis
  28. GRB 050502a : R band observation at Lulin observatory
  29. GRB 050502b : optical observation at Lulin observatory
  30. GRB 050502b: Swift XRT Position
  31. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  32. Swift Detection of the Bright Burst GRB050502b
  33. GRB 050502: Confirmed variability of the afterglow candidate +
  34. GRB 050502: PAIRITEL IR Observations
  35. GRB 050502: ROTSE-III Detection of Possible Counterpart
  36. Swift-BAT Trigger 115881 is not a real GRB
  37. Swift/BAT possible detection of a weak burst GRB050430
  38. GRB 050401: Rc observation
  39. GRB050416a: Radio Detection
  40. GRB 050422: Swift-UVOT observation
  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: Further Analysis of IR imaging
  46. GRB050421: Radio Observations
  47. GRB050421: Radio Observations
  48. GRB 050421: Swift-UVOT observation
  49. GRB 050421: IR Observations
  50. GRB 050421: ROTSE-III Optical Limits
  51. GRB 050421: NIR observations re-examination
  52. GRB050421
  53. GRB 050421: early Swift XRT analysis results
  54. GRB 050421: NIR observations
  55. GRB050421: P60 Observations
  56. GRB 050421: Optical observations at the INT
  57. Swift Detection of GRB050421
  58. GRB 050416b: Tentative Swift XRT Position
  59. GRB 050315: potential host galaxy
  60. GRB050326: analysis of the XMM-Newton observation
  61. GRB 050412: Chandra observations
  62. Swift-BAT detection of the bright and long GRB 050418
  63. GRB 050416: Mitsume optical observation
  64. GRB 050416 : optical observation at Xinglong observatory
  65. GRB 050416B: optical observations
  66. GRB 050416: Swift/UVOT refined analysis
  67. Swift-BAT detection of GRB 050416b
  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: KAIT observations
  75. GRB050416: P200 NIR Observations
  76. GRB 050416: Swift XRT Position
  77. GRB 050416: Radio observations
  78. Confirmation of OT for GRB050416
  79. GRB050416: P60 Afterglow Candidate
  80. Swift BAT/XRT Detection of GRB 050416
  81. GRB 050412: Subaru observations
  82. GRB050408: optical observation
  83. GRB 050412: PROMPT VRcIc Observations
  84. GRB 050412: optical limit
  85. GRB 050412: optical observations
  86. GRB 050408: refined XRT analysis, no jet break seen yet
  87. GRB 050412: early Swift XRT analysis results
  88. GRB 050412 : XingLong optical observation
  89. GRB 050412: Swift-BAT refined analysis
  90. GRB 050412: ANU 2.3m observations
  91. GRB 050412: Early Optical/Ultraviolet Observations with
  92. GRB 050412: UVOT transient not in XRT error circle
  93. GRB 050412: LCO Optical Observations
  94. GRB 050412: Optical observations
  95. GRB050412: P60 Observations
  96. GRB 050412: Swift XRT Position
  97. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  98. GRB 050412: IR Observations
  99. GRB050408: Radio Observations
  100. GRB 050401: Optical limit

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