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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"

45716 results found.

  1. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  2. GRB 050505 UVOT
  3. GRB050505: Optical Afterglow Candidate
  4. GRB 050505: Swift XRT Position
  5. GRB050505 Swift-BAT refined analysis
  6. GRB 050502a: Optical Observations
  7. GRB 050416b:Swift XRT afterglow upper limits
  8. GRB 050416b:Swift XRT afterglow upper limits
  9. Swift-BAT detection of GRB050505
  10. GRB 050504: Swift XRT position
  11. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  12. GRB050502b: Afterglow Confirmation
  13. GRB050502: P200 Observations (Correction)
  14. GRB050502: P200 Observations
  15. GRB 050504 : R band observation at Lulin observatory
  16. Swift UVOT observation of GRB 050504
  17. GRB 050504, R band Observations
  18. GRB050504: Faulkes North optical robotic limit
  19. GRB 050502b, V band Observations
  20. GRB050504: P60 Observations
  21. GRB 050504: A long GRB detected with INTEGRAL
  22. GRB (?) 050504: IR Observations, Intriguing Source
  23. GRB 050502b, Optical observations
  24. GRB050502a: P60 Observations (Correction)
  25. GRB050502a: P60 Observations
  26. Renewal of SGR 1806-20 activity
  27. GRB 050502a: RBO Observations
  28. GRB 050502A: WSRT Radio Observations
  29. GRB050502A: Optical Observations
  30. GRB050502B Swift-BAT refined analysis
  31. GRB050502B: I band source in XRT error circle
  32. Swift UVOT refined analysis
  33. Retraction of Swift-BAT trigger 116145
  34. GRB 050502a : R band observation at Lulin observatory
  35. GRB 050502b : optical observation at Lulin observatory
  36. GRB 050502b: Swift XRT Position
  37. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  38. GRB050502B: Optical Limits from ANU 1m
  39. Swift Detection of the Bright Burst GRB050502b
  40. GRB 050502: INTEGRAL results
  41. GRB050502: ANU 1m optical Observations
  42. GRB 050502: Confirmed variability of the afterglow candidate +
  43. GRB 050502: PAIRITEL IR Observations
  44. GRB050502 - Correction on the Optical Candidate from the Liverpool
  45. GRB050502 - Optical Candidate from the Liverpool Telescope
  46. GRB 050502 - A long GRB detected with INTEGRAL
  47. GRB 050502: ROTSE-III Detection of Possible Counterpart
  48. Swift-BAT Trigger 115881 is not a real GRB
  49. Swift/BAT possible detection of a weak burst GRB050430
  50. GRB 050401: Rc observation
  51. GRB050416a: Radio Detection
  52. GRB 050422: Swift-UVOT observation
  53. GRB 050422: Swift-BAT refined analysis
  54. GRB 050422: Swift XRT Position
  55. Swift Detection of GRB 050422
  56. GRB 050421: NIR observations
  57. GRB 050416: Optical/NIR observations
  58. GRB 050421: SLOTIS observations
  59. GRB 050421: Further Analysis of IR imaging
  60. GRB050421: Radio Observations
  61. GRB050421: Radio Observations
  62. GRB 050421: Swift-UVOT observation
  63. GRB 050421: IR Observations
  64. GRB 050421: Swift-BAT refined analysis
  65. GRB 050421: ROTSE-III Optical Limits
  66. GRB 050421: NIR observations re-examination
  67. GRB050421
  68. GRB 050421: early Swift XRT analysis results
  69. GRB 050421: NIR observations
  70. GRB050421: P60 Observations
  71. GRB 050421: BOOTES-2 simultaneous optical observations
  72. GRB 050421: Optical observations at the INT
  73. Swift Detection of GRB050421
  74. GRB 050416b: Tentative Swift XRT Position
  75. GRB 050315: potential host galaxy
  76. GRB050326: analysis of the XMM-Newton observation
  77. GRB050418: Null Optical Observations
  78. GRB 050412: Chandra observations
  79. GRB050416A, optical observations
  80. GRB 050418: Swift-BAT refined analysis
  81. Swift-BAT detection of the bright and long GRB 050418
  82. GRB 050416: Mitsume optical observation
  83. GRB 050416 : optical observation at Xinglong observatory
  84. GRB 050416B: optical observations
  85. GRB 050416b: Swift-BAT refined analysis
  86. GRB 050416b: LCO observations
  87. GRB 050416b: LCO observations
  88. GRB050416B: IR observations
  89. GRB 050416: Swift/UVOT refined analysis
  90. Swift-BAT detection of GRB 050416b
  91. IBAS GRB Alert # 2463: not a GRB
  92. GRB050412: Radio Observations
  93. GRB 050416: Swift/UVOT detection of afterglow emission
  94. GRB050416: Refined Swift-XRT analysis
  95. GRB050416: Maidanak optical observations
  96. GRB 050416: Swift-BAT refined analysis
  97. GRB 050416: ART observations
  98. GRB 050416,optical observation
  99. GRB 050416: KAIT observations
  100. GRB050416: P200 NIR Observations

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