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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').

18174 results found.

  1. GRB 050504: Swift XRT position
  2. Swift UVOT observation of GRB 050504
  3. GRB 050502b, V band Observations
  4. GRB050502B Swift-BAT refined analysis
  5. GRB050502B: I band source in XRT error circle
  6. Swift UVOT refined analysis
  7. Retraction of Swift-BAT trigger 116145
  8. GRB 050502b : optical observation at Lulin observatory
  9. GRB 050502b: Swift XRT Position
  10. GRB050502B: Optical Limits from ANU 1m
  11. Swift Detection of the Bright Burst GRB050502b
  12. GRB050502: ANU 1m optical Observations
  13. Swift-BAT Trigger 115881 is not a real GRB
  14. Swift/BAT possible detection of a weak burst GRB050430
  15. GRB 050401: Rc observation
  16. GRB050416a: Radio Detection
  17. GRB 050422: Swift-UVOT observation
  18. GRB 050422: Swift-BAT refined analysis
  19. GRB 050422: Swift XRT Position
  20. Swift Detection of GRB 050422
  21. GRB 050421: SLOTIS observations
  22. GRB050421: Radio Observations
  23. GRB050421: Radio Observations
  24. GRB 050421: Swift-UVOT observation
  25. GRB 050421: Swift-BAT refined analysis
  26. GRB 050421: ROTSE-III Optical Limits
  27. GRB 050421: early Swift XRT analysis results
  28. GRB 050421: BOOTES-2 simultaneous optical observations
  29. GRB 050421: Optical observations at the INT
  30. Swift Detection of GRB050421
  31. GRB 050416b: Tentative Swift XRT Position
  32. GRB050326: analysis of the XMM-Newton observation
  33. GRB 050418: Swift-BAT refined analysis
  34. Swift-BAT detection of the bright and long GRB 050418
  35. GRB 050416B: optical observations
  36. GRB 050416b: Swift-BAT refined analysis
  37. GRB 050416: Swift/UVOT refined analysis
  38. Swift-BAT detection of GRB 050416b
  39. GRB050412: Radio Observations
  40. GRB 050416: Swift/UVOT detection of afterglow emission
  41. GRB050416: Refined Swift-XRT analysis
  42. GRB050416: Maidanak optical observations
  43. GRB 050416: Swift-BAT refined analysis
  44. GRB 050416,optical observation
  45. GRB 050416: KAIT observations
  46. GRB 050416: Swift XRT Position
  47. GRB 050416: Radio observations
  48. Confirmation of OT for GRB050416
  49. GRB050416: P60 Afterglow Candidate
  50. Swift BAT/XRT Detection of GRB 050416
  51. GRB 050412: Subaru observations
  52. GRB 050412: optical limit
  53. GRB 050412: optical observations
  54. GRB 050408: refined XRT analysis, no jet break seen yet
  55. GRB 050412: early Swift XRT analysis results
  56. GRB 050412: Swift-BAT refined analysis
  57. GRB 050412: ANU 2.3m observations
  58. GRB 050412: Early Optical/Ultraviolet Observations with
  59. GRB 050412: retraction of UVOT transient report
  60. GRB 050412: UVOT transient not in XRT error circle
  61. GRB 050412: Swift XRT Position
  62. GRB050412: optical limit before and during GRB
  63. GRB050412: ROTSE-III Optical Limits
  64. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  65. GRB 050412: IR Observations
  66. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  67. GRB 050410, optical observations
  68. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  69. GRB 050410 R band Optical Observations
  70. GRB050410 : Null detection report
  71. GRB 050410, optical observations
  72. GRB050410: Radio Observations
  73. GRB 050408: Swift XRT measurement of possible jet break
  74. GRB050410: MASTER optical observations
  75. GRB 050410: Early observations with Swift-UVOT
  76. Swift-BAT detection of GRB 050410
  77. GRB 050410: Swift XRT Position
  78. GRB 050408: Properties of the Host Galaxy
  79. GRB 050408: Swift XRT analysis
  80. GRB 050408, optical observations
  81. GRB050408: REM NIR and Optical observation
  82. GRB 050408 Optical Observations
  83. GRB 050408: Optical afterglow confirmed
  84. GRB 050408, optical observations
  85. GRB 050408 optical candidate
  86. GRB 050408: Swift XRT Position
  87. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  88. GRB 050406: early Swift XRT analysis results
  89. GRB 050406 BAT refined analysis
  90. GRB 050406: Early observations with Swift-UVOT
  91. GRB 050406: Swift XRT Position
  92. Swift-BAT detection of GRB 050406
  93. Konus-Wind observation of GRB 050401
  94. GRB050401: Radio observation at 610 MHz with GMRT
  95. GRB 050401: VLT spectroscopic redshift
  96. GRB 050401 Optical Observations
  97. GRB050401: Maidanak optical observation
  98. GRB 050401 BAT refined analysis
  99. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  100. GRB 050402A: IR Observations

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