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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"

28199 results found.

  1. GRB 050504: Swift XRT position
  2. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  3. GRB050502b: Afterglow Confirmation
  4. GRB050502: P200 Observations (Correction)
  5. GRB050502: P200 Observations
  6. GRB050502a: P60 Observations (Correction)
  7. GRB050502a: P60 Observations
  8. GRB 050502a: RBO Observations
  9. GRB 050502A: WSRT Radio Observations
  10. GRB050502A: Optical Observations
  11. GRB050502B Swift-BAT refined analysis
  12. GRB050502B: I band source in XRT error circle
  13. Swift UVOT refined analysis
  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: Confirmed variability of the afterglow candidate +
  20. GRB 050502: PAIRITEL IR Observations
  21. GRB 050502: ROTSE-III Detection of Possible Counterpart
  22. Swift-BAT Trigger 115881 is not a real GRB
  23. Swift/BAT possible detection of a weak burst GRB050430
  24. GRB 050401: Rc observation
  25. GRB050416a: Radio Detection
  26. GRB 050422: Swift-UVOT observation
  27. GRB 050422: Swift XRT Position
  28. Swift Detection of GRB 050422
  29. GRB 050421: NIR observations
  30. GRB 050416: Optical/NIR observations
  31. GRB 050421: Further Analysis of IR imaging
  32. GRB050421: Radio Observations
  33. GRB050421: Radio Observations
  34. GRB 050421: Swift-UVOT observation
  35. GRB 050421: IR Observations
  36. GRB 050421: ROTSE-III Optical Limits
  37. GRB 050421: NIR observations re-examination
  38. GRB050421
  39. GRB 050421: early Swift XRT analysis results
  40. GRB 050421: NIR observations
  41. GRB050421: P60 Observations
  42. GRB 050421: Optical observations at the INT
  43. Swift Detection of GRB050421
  44. GRB 050416b: Tentative Swift XRT Position
  45. GRB 050315: potential host galaxy
  46. GRB050326: analysis of the XMM-Newton observation
  47. GRB 050412: Chandra observations
  48. Swift-BAT detection of the bright and long GRB 050418
  49. GRB 050416: Mitsume optical observation
  50. GRB 050416 : optical observation at Xinglong observatory
  51. GRB 050416B: optical observations
  52. GRB 050416: Swift/UVOT refined analysis
  53. Swift-BAT detection of GRB 050416b
  54. GRB050412: Radio Observations
  55. GRB 050416: Swift/UVOT detection of afterglow emission
  56. GRB050416: Refined Swift-XRT analysis
  57. GRB050416: Maidanak optical observations
  58. GRB 050416: Swift-BAT refined analysis
  59. GRB 050416: ART observations
  60. GRB 050416: KAIT observations
  61. GRB050416: P200 NIR Observations
  62. GRB 050416: Swift XRT Position
  63. GRB 050416: Radio observations
  64. Confirmation of OT for GRB050416
  65. GRB050416: P60 Afterglow Candidate
  66. Swift BAT/XRT Detection of GRB 050416
  67. GRB 050412: Subaru observations
  68. GRB050408: optical observation
  69. GRB 050412: PROMPT VRcIc Observations
  70. GRB 050412: optical limit
  71. GRB 050412: optical observations
  72. GRB 050408: refined XRT analysis, no jet break seen yet
  73. GRB 050412: early Swift XRT analysis results
  74. GRB 050412 : XingLong optical observation
  75. GRB 050412: Swift-BAT refined analysis
  76. GRB 050412: ANU 2.3m observations
  77. GRB 050412: Early Optical/Ultraviolet Observations with
  78. GRB 050412: UVOT transient not in XRT error circle
  79. GRB 050412: LCO Optical Observations
  80. GRB 050412: Optical observations
  81. GRB050412: P60 Observations
  82. GRB 050412: Swift XRT Position
  83. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  84. GRB 050412: IR Observations
  85. GRB050408: Radio Observations
  86. GRB 050401: Optical limit
  87. GRB 050408: Optical limit
  88. GRB050410: P60 Observations
  89. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  90. GRB 050410, optical observations
  91. GRB 050408: PROMPT VRcIc Observations
  92. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  93. GRB050410 : Null detection report
  94. GRB 050410, optical observations
  95. GRB050410: Radio Observations
  96. GRB 050408: Swift XRT measurement of possible jet break
  97. GRB 050410: Early observations with Swift-UVOT
  98. Swift-BAT detection of GRB 050410
  99. GRB 050410: Swift XRT Position
  100. GRB 050408: Retraction of Proposed Host Galaxy

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