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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').

18187 results found.

  1. Swift-BAT detection of GRB 050507
  2. GRB 050505: early time observations
  3. GRB 050505 - Faulkes Telescope North observations
  4. GRB 050502a: Swift XRT Upper Limit
  5. GRB 050505, simultaneous optical observation
  6. GRB 050505: Further Swift UVOT observations.
  7. GRB050416A : 1 GHz limit from GMRT
  8. GRB 050505 UVOT
  9. GRB 050505: Swift XRT Position
  10. GRB050505 Swift-BAT refined analysis
  11. GRB 050416b:Swift XRT afterglow upper limits
  12. GRB 050416b:Swift XRT afterglow upper limits
  13. Swift-BAT detection of GRB050505
  14. GRB 050504: Swift XRT position
  15. Swift UVOT observation of GRB 050504
  16. GRB 050502b, V band Observations
  17. GRB050502B Swift-BAT refined analysis
  18. GRB050502B: I band source in XRT error circle
  19. Swift UVOT refined analysis
  20. Retraction of Swift-BAT trigger 116145
  21. GRB 050502b : optical observation at Lulin observatory
  22. GRB 050502b: Swift XRT Position
  23. GRB050502B: Optical Limits from ANU 1m
  24. Swift Detection of the Bright Burst GRB050502b
  25. GRB050502: ANU 1m optical Observations
  26. Swift-BAT Trigger 115881 is not a real GRB
  27. Swift/BAT possible detection of a weak burst GRB050430
  28. GRB 050401: Rc observation
  29. GRB050416a: Radio Detection
  30. GRB 050422: Swift-UVOT observation
  31. GRB 050422: Swift-BAT refined analysis
  32. GRB 050422: Swift XRT Position
  33. Swift Detection of GRB 050422
  34. GRB 050421: SLOTIS observations
  35. GRB050421: Radio Observations
  36. GRB050421: Radio Observations
  37. GRB 050421: Swift-UVOT observation
  38. GRB 050421: Swift-BAT refined analysis
  39. GRB 050421: ROTSE-III Optical Limits
  40. GRB 050421: early Swift XRT analysis results
  41. GRB 050421: BOOTES-2 simultaneous optical observations
  42. GRB 050421: Optical observations at the INT
  43. Swift Detection of GRB050421
  44. GRB 050416b: Tentative Swift XRT Position
  45. GRB050326: analysis of the XMM-Newton observation
  46. GRB 050418: Swift-BAT refined analysis
  47. Swift-BAT detection of the bright and long GRB 050418
  48. GRB 050416B: optical observations
  49. GRB 050416b: Swift-BAT refined analysis
  50. GRB 050416: Swift/UVOT refined analysis
  51. Swift-BAT detection of GRB 050416b
  52. GRB050412: Radio Observations
  53. GRB 050416: Swift/UVOT detection of afterglow emission
  54. GRB050416: Refined Swift-XRT analysis
  55. GRB050416: Maidanak optical observations
  56. GRB 050416: Swift-BAT refined analysis
  57. GRB 050416,optical observation
  58. GRB 050416: KAIT observations
  59. GRB 050416: Swift XRT Position
  60. GRB 050416: Radio observations
  61. Confirmation of OT for GRB050416
  62. GRB050416: P60 Afterglow Candidate
  63. Swift BAT/XRT Detection of GRB 050416
  64. GRB 050412: Subaru observations
  65. GRB 050412: optical limit
  66. GRB 050412: optical observations
  67. GRB 050408: refined XRT analysis, no jet break seen yet
  68. GRB 050412: early Swift XRT analysis results
  69. GRB 050412: Swift-BAT refined analysis
  70. GRB 050412: ANU 2.3m observations
  71. GRB 050412: Early Optical/Ultraviolet Observations with
  72. GRB 050412: retraction of UVOT transient report
  73. GRB 050412: UVOT transient not in XRT error circle
  74. GRB 050412: Swift XRT Position
  75. GRB050412: optical limit before and during GRB
  76. GRB050412: ROTSE-III Optical Limits
  77. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  78. GRB 050412: IR Observations
  79. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  80. GRB 050410, optical observations
  81. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  82. GRB 050410 R band Optical Observations
  83. GRB050410 : Null detection report
  84. GRB 050410, optical observations
  85. GRB050410: Radio Observations
  86. GRB 050408: Swift XRT measurement of possible jet break
  87. GRB050410: MASTER optical observations
  88. GRB 050410: Early observations with Swift-UVOT
  89. Swift-BAT detection of GRB 050410
  90. GRB 050410: Swift XRT Position
  91. GRB 050408: Properties of the Host Galaxy
  92. GRB 050408: Swift XRT analysis
  93. GRB 050408, optical observations
  94. GRB050408: REM NIR and Optical observation
  95. GRB 050408 Optical Observations
  96. GRB 050408: Optical afterglow confirmed
  97. GRB 050408, optical observations
  98. GRB 050408 optical candidate
  99. GRB 050408: Swift XRT Position
  100. Swift-UVOT Optical Counterpart Candidate to XRF 050406

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