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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').

18183 results found.

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

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