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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"

41734 results found.

  1. GRB 050502a: Optical Observations
  2. GRB 050416b:Swift XRT afterglow upper limits
  3. GRB 050416b:Swift XRT afterglow upper limits
  4. Swift-BAT detection of GRB050505
  5. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  6. GRB050502b: Afterglow Confirmation
  7. GRB050502: P200 Observations (Correction)
  8. GRB050502: P200 Observations
  9. GRB 050504 : R band observation at Lulin observatory
  10. Swift UVOT observation of GRB 050504
  11. GRB 050504, R band Observations
  12. GRB050504: Faulkes North optical robotic limit
  13. GRB 050502b, V band Observations
  14. GRB050504: P60 Observations
  15. GRB 050504: A long GRB detected with INTEGRAL
  16. GRB (?) 050504: IR Observations, Intriguing Source
  17. GRB 050502b, Optical observations
  18. GRB050502a: P60 Observations (Correction)
  19. GRB050502a: P60 Observations
  20. Renewal of SGR 1806-20 activity
  21. GRB 050502a: RBO Observations
  22. GRB 050502A: WSRT Radio Observations
  23. GRB050502A: Optical Observations
  24. GRB050502B Swift-BAT refined analysis
  25. GRB050502B: I band source in XRT error circle
  26. Swift UVOT refined analysis
  27. GRB 050502a : R band observation at Lulin observatory
  28. GRB 050502b : optical observation at Lulin observatory
  29. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  30. GRB050502B: Optical Limits from ANU 1m
  31. Swift Detection of the Bright Burst GRB050502b
  32. GRB050502: ANU 1m optical Observations
  33. GRB 050502: PAIRITEL IR Observations
  34. GRB 050502 - A long GRB detected with INTEGRAL
  35. GRB 050502: ROTSE-III Detection of Possible Counterpart
  36. Swift/BAT possible detection of a weak burst GRB050430
  37. GRB 050401: Rc observation
  38. GRB050416a: Radio Detection
  39. GRB 050422: Swift-UVOT observation
  40. GRB 050422: Swift-BAT refined analysis
  41. Swift Detection of GRB 050422
  42. GRB 050421: NIR observations
  43. GRB 050416: Optical/NIR observations
  44. GRB 050421: SLOTIS 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: Swift-BAT refined analysis
  51. GRB 050421: ROTSE-III Optical Limits
  52. GRB 050421: NIR observations re-examination
  53. GRB050421
  54. GRB 050421: early Swift XRT analysis results
  55. GRB 050421: NIR observations
  56. GRB050421: P60 Observations
  57. GRB 050421: BOOTES-2 simultaneous optical observations
  58. GRB 050421: Optical observations at the INT
  59. Swift Detection of GRB050421
  60. GRB 050416b: Tentative Swift XRT Position
  61. GRB 050315: potential host galaxy
  62. GRB050326: analysis of the XMM-Newton observation
  63. GRB050418: Null Optical Observations
  64. GRB 050412: Chandra observations
  65. GRB050416A, optical observations
  66. GRB 050418: Swift-BAT refined analysis
  67. GRB 050416: Mitsume optical observation
  68. GRB 050416 : optical observation at Xinglong observatory
  69. GRB 050416B: optical observations
  70. GRB 050416b: LCO observations
  71. GRB 050416b: LCO observations
  72. GRB050416B: IR observations
  73. GRB 050416: Swift/UVOT refined analysis
  74. Swift-BAT detection of GRB 050416b
  75. GRB050412: Radio Observations
  76. GRB 050416: Swift/UVOT detection of afterglow emission
  77. GRB050416: Refined Swift-XRT analysis
  78. GRB050416: Maidanak optical observations
  79. GRB 050416: ART observations
  80. GRB 050416,optical observation
  81. GRB 050416: KAIT observations
  82. GRB050416: P200 NIR Observations
  83. GRB 050416: Radio observations
  84. Confirmation of OT for GRB050416
  85. GRB050416: P60 Afterglow Candidate
  86. Swift BAT/XRT Detection of GRB 050416
  87. GRB 050412: Subaru observations
  88. GRB 050408: RTT150 optical observations
  89. GRB050408: optical observation
  90. GRB 050412: PROMPT VRcIc Observations
  91. GRB 050408: Kuiper 1.5m observations
  92. GRB 050412: optical limit
  93. GRB 050412: optical observations
  94. GRB 050408: refined XRT analysis, no jet break seen yet
  95. GRB 050412 : XingLong optical observation
  96. GRB 050412: Swift-BAT refined analysis
  97. GRB 050412: ANU 2.3m observations
  98. GRB 050412: Early Optical/Ultraviolet Observations with
  99. GRB 050412: UVOT transient not in XRT error circle
  100. GRB 050412: Optical limit

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