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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"

36013 results found.

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