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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"

36215 results found.

  1. GRB 050509b: Swift XRT Position
  2. GRB 050509B: ROTSE-III Optical Limits
  3. GRB 050509a: Swift XRT Position
  4. Swift-BAT detection of GRB 050507
  5. GRB 050505: Keck I-band Magnitude
  6. GRB 050505: early time observations
  7. GRB 050505 - Faulkes Telescope North observations
  8. GRB 050502a: Swift XRT Upper Limit
  9. GRB 050505, simultaneous optical observation
  10. GRB 050505: Further Swift UVOT observations.
  11. GRB050505: AAVSO observations
  12. GRB050416A : 1 GHz limit from GMRT
  13. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  14. GRB 050505 UVOT
  15. GRB050505: Optical Afterglow Candidate
  16. GRB 050505: Swift XRT Position
  17. GRB 050502a: Optical Observations
  18. GRB 050416b:Swift XRT afterglow upper limits
  19. GRB 050416b:Swift XRT afterglow upper limits
  20. GRB 050504: Swift XRT position
  21. GRB050502: P200 Observations (Correction)
  22. GRB050502: P200 Observations
  23. GRB 050504 : R band observation at Lulin observatory
  24. Swift UVOT observation of GRB 050504
  25. GRB 050504, R band Observations
  26. GRB 050502b, V band Observations
  27. GRB050504: P60 Observations
  28. GRB 050504: A long GRB detected with INTEGRAL
  29. GRB (?) 050504: IR Observations, Intriguing Source
  30. GRB 050502b, Optical observations
  31. GRB050502a: P60 Observations (Correction)
  32. GRB050502a: P60 Observations
  33. Renewal of SGR 1806-20 activity
  34. GRB 050502a: RBO Observations
  35. GRB 050502A: WSRT Radio Observations
  36. GRB050502A: Optical Observations
  37. Swift UVOT refined analysis
  38. Retraction of Swift-BAT trigger 116145
  39. GRB 050502a : R band observation at Lulin observatory
  40. GRB 050502b : optical observation at Lulin observatory
  41. GRB 050502b: Swift XRT Position
  42. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  43. GRB 050502: INTEGRAL results
  44. GRB050502: ANU 1m optical Observations
  45. GRB 050502: Confirmed variability of the afterglow candidate +
  46. GRB 050502: PAIRITEL IR Observations
  47. GRB050502 - Correction on the Optical Candidate from the Liverpool
  48. GRB 050502 - A long GRB detected with INTEGRAL
  49. GRB 050502: ROTSE-III Detection of Possible Counterpart
  50. Swift-BAT Trigger 115881 is not a real GRB
  51. Swift/BAT possible detection of a weak burst GRB050430
  52. GRB 050401: Rc observation
  53. GRB050416a: Radio Detection
  54. GRB 050422: Swift-UVOT observation
  55. GRB 050422: Swift-BAT refined analysis
  56. GRB 050422: Swift XRT Position
  57. Swift Detection of GRB 050422
  58. GRB 050421: NIR observations
  59. GRB 050416: Optical/NIR observations
  60. GRB 050421: SLOTIS observations
  61. GRB 050421: Further Analysis of IR imaging
  62. GRB050421: Radio Observations
  63. GRB050421: Radio Observations
  64. GRB 050421: Swift-UVOT observation
  65. GRB 050421: IR Observations
  66. GRB 050421: Swift-BAT refined analysis
  67. GRB 050421: ROTSE-III Optical Limits
  68. GRB 050421: NIR observations re-examination
  69. GRB 050421: early Swift XRT analysis results
  70. GRB 050421: NIR observations
  71. GRB050421: P60 Observations
  72. GRB 050421: BOOTES-2 simultaneous optical observations
  73. GRB 050421: Optical observations at the INT
  74. GRB 050416b: Tentative Swift XRT Position
  75. GRB 050315: potential host galaxy
  76. GRB 050412: Chandra observations
  77. GRB050416A, optical observations
  78. GRB 050418: Swift-BAT refined analysis
  79. Swift-BAT detection of the bright and long GRB 050418
  80. GRB 050416: Mitsume optical observation
  81. GRB 050416 : optical observation at Xinglong observatory
  82. GRB 050416B: optical observations
  83. GRB 050416b: Swift-BAT refined analysis
  84. GRB 050416b: LCO observations
  85. GRB 050416b: LCO observations
  86. GRB050416B: IR observations
  87. GRB 050416: Swift/UVOT refined analysis
  88. Swift-BAT detection of GRB 050416b
  89. IBAS GRB Alert # 2463: not a GRB
  90. GRB050412: Radio Observations
  91. GRB 050416: Swift/UVOT detection of afterglow emission
  92. GRB 050416: Swift-BAT refined analysis
  93. GRB 050416: ART observations
  94. GRB 050416,optical observation
  95. GRB 050416: KAIT observations
  96. GRB050416: P200 NIR Observations
  97. GRB 050416: Swift XRT Position
  98. GRB 050416: Radio observations
  99. Confirmation of OT for GRB050416
  100. GRB050416: P60 Afterglow Candidate

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