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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').

18182 results found.

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

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