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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

18188 results found.

  1. Swift Detection of the Burst GRB050509
  2. Swift-BAT detection of GRB 050507
  3. GRB 050505: early time observations
  4. GRB 050505 - Faulkes Telescope North observations
  5. GRB 050502a: Swift XRT Upper Limit
  6. GRB 050505, simultaneous optical observation
  7. GRB 050505: Further Swift UVOT observations.
  8. GRB050416A : 1 GHz limit from GMRT
  9. GRB 050505 UVOT
  10. GRB 050505: Swift XRT Position
  11. GRB050505 Swift-BAT refined analysis
  12. GRB 050416b:Swift XRT afterglow upper limits
  13. GRB 050416b:Swift XRT afterglow upper limits
  14. Swift-BAT detection of GRB050505
  15. GRB 050504: Swift XRT position
  16. Swift UVOT observation of GRB 050504
  17. GRB 050502b, V band Observations
  18. GRB050502B Swift-BAT refined analysis
  19. GRB050502B: I band source in XRT error circle
  20. Swift UVOT refined analysis
  21. Retraction of Swift-BAT trigger 116145
  22. GRB 050502b : optical observation at Lulin observatory
  23. GRB 050502b: Swift XRT Position
  24. GRB050502B: Optical Limits from ANU 1m
  25. Swift Detection of the Bright Burst GRB050502b
  26. GRB050502: ANU 1m optical Observations
  27. Swift-BAT Trigger 115881 is not a real GRB
  28. Swift/BAT possible detection of a weak burst GRB050430
  29. GRB 050401: Rc observation
  30. GRB050416a: Radio Detection
  31. GRB 050422: Swift-UVOT observation
  32. GRB 050422: Swift-BAT refined analysis
  33. GRB 050422: Swift XRT Position
  34. Swift Detection of GRB 050422
  35. GRB 050421: SLOTIS observations
  36. GRB050421: Radio Observations
  37. GRB050421: Radio Observations
  38. GRB 050421: Swift-UVOT observation
  39. GRB 050421: Swift-BAT refined analysis
  40. GRB 050421: ROTSE-III Optical Limits
  41. GRB 050421: early Swift XRT analysis results
  42. GRB 050421: BOOTES-2 simultaneous optical observations
  43. GRB 050421: Optical observations at the INT
  44. Swift Detection of GRB050421
  45. GRB 050416b: Tentative Swift XRT Position
  46. GRB050326: analysis of the XMM-Newton observation
  47. GRB 050418: Swift-BAT refined analysis
  48. Swift-BAT detection of the bright and long GRB 050418
  49. GRB 050416B: optical observations
  50. GRB 050416b: Swift-BAT refined analysis
  51. GRB 050416: Swift/UVOT refined analysis
  52. Swift-BAT detection of GRB 050416b
  53. GRB050412: Radio Observations
  54. GRB 050416: Swift/UVOT detection of afterglow emission
  55. GRB050416: Refined Swift-XRT analysis
  56. GRB050416: Maidanak optical observations
  57. GRB 050416: Swift-BAT refined analysis
  58. GRB 050416,optical observation
  59. GRB 050416: KAIT observations
  60. GRB 050416: Swift XRT Position
  61. GRB 050416: Radio observations
  62. Confirmation of OT for GRB050416
  63. GRB050416: P60 Afterglow Candidate
  64. Swift BAT/XRT Detection of GRB 050416
  65. GRB 050412: Subaru observations
  66. GRB 050412: optical limit
  67. GRB 050412: optical observations
  68. GRB 050408: refined XRT analysis, no jet break seen yet
  69. GRB 050412: early Swift XRT analysis results
  70. GRB 050412: Swift-BAT refined analysis
  71. GRB 050412: ANU 2.3m observations
  72. GRB 050412: Early Optical/Ultraviolet Observations with
  73. GRB 050412: retraction of UVOT transient report
  74. GRB 050412: UVOT transient not in XRT error circle
  75. GRB 050412: Swift XRT Position
  76. GRB050412: optical limit before and during GRB
  77. GRB050412: ROTSE-III Optical Limits
  78. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  79. GRB 050412: IR Observations
  80. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  81. GRB 050410, optical observations
  82. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  83. GRB 050410 R band Optical Observations
  84. GRB050410 : Null detection report
  85. GRB 050410, optical observations
  86. GRB050410: Radio Observations
  87. GRB 050408: Swift XRT measurement of possible jet break
  88. GRB050410: MASTER optical observations
  89. GRB 050410: Early observations with Swift-UVOT
  90. Swift-BAT detection of GRB 050410
  91. GRB 050410: Swift XRT Position
  92. GRB 050408: Properties of the Host Galaxy
  93. GRB 050408: Swift XRT analysis
  94. GRB 050408, optical observations
  95. GRB050408: REM NIR and Optical observation
  96. GRB 050408 Optical Observations
  97. GRB 050408: Optical afterglow confirmed
  98. GRB 050408, optical observations
  99. GRB 050408 optical candidate
  100. GRB 050408: Swift XRT Position

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