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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"

37700 results found.

  1. GRB 050505: Further Swift UVOT observations.
  2. GRB050505: AAVSO observations
  3. GRB050416A : 1 GHz limit from GMRT
  4. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  5. GRB 050505 UVOT
  6. GRB050505: Optical Afterglow Candidate
  7. GRB 050505: Swift XRT Position
  8. GRB 050502a: Optical Observations
  9. GRB 050416b:Swift XRT afterglow upper limits
  10. GRB 050416b:Swift XRT afterglow upper limits
  11. GRB 050504: Swift XRT position
  12. GRB050502: P200 Observations (Correction)
  13. GRB050502: P200 Observations
  14. GRB 050504 : R band observation at Lulin observatory
  15. Swift UVOT observation of GRB 050504
  16. GRB 050504, R band Observations
  17. GRB 050502b, V band Observations
  18. GRB050504: P60 Observations
  19. GRB 050504: A long GRB detected with INTEGRAL
  20. GRB (?) 050504: IR Observations, Intriguing Source
  21. GRB 050502b, Optical observations
  22. GRB050502a: P60 Observations (Correction)
  23. GRB050502a: P60 Observations
  24. Renewal of SGR 1806-20 activity
  25. GRB 050502a: RBO Observations
  26. GRB 050502A: WSRT Radio Observations
  27. GRB050502A: Optical Observations
  28. Swift UVOT refined analysis
  29. Retraction of Swift-BAT trigger 116145
  30. GRB 050502a : R band observation at Lulin observatory
  31. GRB 050502b : optical observation at Lulin observatory
  32. GRB 050502b: Swift XRT Position
  33. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  34. GRB 050502: INTEGRAL results
  35. GRB050502: ANU 1m optical Observations
  36. GRB 050502: Confirmed variability of the afterglow candidate +
  37. GRB 050502: PAIRITEL IR Observations
  38. GRB050502 - Correction on the Optical Candidate from the Liverpool
  39. GRB 050502 - A long GRB detected with INTEGRAL
  40. GRB 050502: ROTSE-III Detection of Possible Counterpart
  41. Swift-BAT Trigger 115881 is not a real GRB
  42. Swift/BAT possible detection of a weak burst GRB050430
  43. GRB 050401: Rc observation
  44. GRB050416a: Radio Detection
  45. GRB 050422: Swift-UVOT observation
  46. GRB 050422: Swift-BAT refined analysis
  47. GRB 050422: Swift XRT Position
  48. Swift Detection of GRB 050422
  49. GRB 050421: NIR observations
  50. GRB 050416: Optical/NIR observations
  51. GRB 050421: SLOTIS observations
  52. GRB 050421: Further Analysis of IR imaging
  53. GRB050421: Radio Observations
  54. GRB050421: Radio Observations
  55. GRB 050421: Swift-UVOT observation
  56. GRB 050421: IR Observations
  57. GRB 050421: Swift-BAT refined analysis
  58. GRB 050421: ROTSE-III Optical Limits
  59. GRB 050421: NIR observations re-examination
  60. GRB 050421: early Swift XRT analysis results
  61. GRB 050421: NIR observations
  62. GRB050421: P60 Observations
  63. GRB 050421: BOOTES-2 simultaneous optical observations
  64. GRB 050421: Optical observations at the INT
  65. GRB 050416b: Tentative Swift XRT Position
  66. GRB 050315: potential host galaxy
  67. GRB 050412: Chandra observations
  68. GRB050416A, optical observations
  69. GRB 050418: Swift-BAT refined analysis
  70. Swift-BAT detection of the bright and long GRB 050418
  71. GRB 050416: Mitsume optical observation
  72. GRB 050416 : optical observation at Xinglong observatory
  73. GRB 050416B: optical observations
  74. GRB 050416b: Swift-BAT refined analysis
  75. GRB 050416b: LCO observations
  76. GRB 050416b: LCO observations
  77. GRB050416B: IR observations
  78. GRB 050416: Swift/UVOT refined analysis
  79. Swift-BAT detection of GRB 050416b
  80. IBAS GRB Alert # 2463: not a GRB
  81. GRB050412: Radio Observations
  82. GRB 050416: Swift/UVOT detection of afterglow emission
  83. GRB 050416: Swift-BAT refined analysis
  84. GRB 050416: ART observations
  85. GRB 050416,optical observation
  86. GRB 050416: KAIT observations
  87. GRB050416: P200 NIR Observations
  88. GRB 050416: Swift XRT Position
  89. GRB 050416: Radio observations
  90. Confirmation of OT for GRB050416
  91. GRB050416: P60 Afterglow Candidate
  92. Swift BAT/XRT Detection of GRB 050416
  93. GRB 050412: Subaru observations
  94. GRB 050408: RTT150 optical observations
  95. GRB 050412: PROMPT VRcIc Observations
  96. GRB 050408: Kuiper 1.5m observations
  97. GRB 050412: optical limit
  98. GRB 050412: optical observations
  99. GRB 050408: refined XRT analysis, no jet break seen yet
  100. GRB 050412: early Swift XRT analysis results

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