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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').

18309 results found.

  1. GRB050509B: Optical/Infared observations
  2. GRB 050509b: Swift/UVOT follow-up measurements
  3. GRB 050509b Milagro GeV/TeV Observations
  4. GRB050509B: Optical observations at the Very Large Telescope
  5. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  6. GRB 050509a: Swift-BAT refined analysis
  7. GRB 050509B: WSRT Radio Observations
  8. GRB 050505: SARA Observations
  9. Swift UVOT Follow-up Observations of GRB 050509B
  10. GRB 050509B, Optical Observations
  11. GRB 050509B: Swift/XRT refined analysis
  12. GRB050509a: Swift UVOT observations
  13. GRB 050509b: Optical observations
  14. GRB 050509b: Possible Optical Counterpart
  15. GRB 050509A: Optical observations
  16. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  17. GRB 050509b: optical observations
  18. GRB 050509b: Swift XRT Position
  19. GRB 050509B: ROTSE-III Optical Limits
  20. Swift Detection of GRB050509b: A short duration burst
  21. GRB 050509a: Swift XRT Position
  22. Swift Detection of the Burst GRB050509
  23. Swift-BAT detection of GRB 050507
  24. GRB 050505: early time observations
  25. GRB 050505 - Faulkes Telescope North observations
  26. GRB 050502a: Swift XRT Upper Limit
  27. GRB 050505, simultaneous optical observation
  28. GRB 050505: Further Swift UVOT observations.
  29. GRB050416A : 1 GHz limit from GMRT
  30. GRB 050505 UVOT
  31. GRB 050505: Swift XRT Position
  32. GRB050505 Swift-BAT refined analysis
  33. GRB 050416b:Swift XRT afterglow upper limits
  34. GRB 050416b:Swift XRT afterglow upper limits
  35. Swift-BAT detection of GRB050505
  36. GRB 050504: Swift XRT position
  37. Swift UVOT observation of GRB 050504
  38. GRB 050502b, V band Observations
  39. GRB050502B Swift-BAT refined analysis
  40. GRB050502B: I band source in XRT error circle
  41. Swift UVOT refined analysis
  42. Retraction of Swift-BAT trigger 116145
  43. GRB 050502b : optical observation at Lulin observatory
  44. GRB 050502b: Swift XRT Position
  45. GRB050502B: Optical Limits from ANU 1m
  46. Swift Detection of the Bright Burst GRB050502b
  47. GRB050502: ANU 1m optical Observations
  48. Swift-BAT Trigger 115881 is not a real GRB
  49. Swift/BAT possible detection of a weak burst GRB050430
  50. GRB 050401: Rc observation
  51. GRB050416a: Radio Detection
  52. GRB 050422: Swift-UVOT observation
  53. GRB 050422: Swift-BAT refined analysis
  54. GRB 050422: Swift XRT Position
  55. Swift Detection of GRB 050422
  56. GRB 050421: SLOTIS observations
  57. GRB050421: Radio Observations
  58. GRB050421: Radio Observations
  59. GRB 050421: Swift-UVOT observation
  60. GRB 050421: Swift-BAT refined analysis
  61. GRB 050421: ROTSE-III Optical Limits
  62. GRB 050421: early Swift XRT analysis results
  63. GRB 050421: BOOTES-2 simultaneous optical observations
  64. GRB 050421: Optical observations at the INT
  65. Swift Detection of GRB050421
  66. GRB 050416b: Tentative Swift XRT Position
  67. GRB050326: analysis of the XMM-Newton observation
  68. GRB 050418: Swift-BAT refined analysis
  69. Swift-BAT detection of the bright and long GRB 050418
  70. GRB 050416B: optical observations
  71. GRB 050416b: Swift-BAT refined analysis
  72. GRB 050416: Swift/UVOT refined analysis
  73. Swift-BAT detection of GRB 050416b
  74. GRB050412: Radio Observations
  75. GRB 050416: Swift/UVOT detection of afterglow emission
  76. GRB050416: Refined Swift-XRT analysis
  77. GRB050416: Maidanak optical observations
  78. GRB 050416: Swift-BAT refined analysis
  79. GRB 050416,optical observation
  80. GRB 050416: KAIT observations
  81. GRB 050416: Swift XRT Position
  82. GRB 050416: Radio observations
  83. Confirmation of OT for GRB050416
  84. GRB050416: P60 Afterglow Candidate
  85. Swift BAT/XRT Detection of GRB 050416
  86. GRB 050412: Subaru observations
  87. GRB 050412: optical limit
  88. GRB 050412: optical observations
  89. GRB 050408: refined XRT analysis, no jet break seen yet
  90. GRB 050412: early Swift XRT analysis results
  91. GRB 050412: Swift-BAT refined analysis
  92. GRB 050412: ANU 2.3m observations
  93. GRB 050412: Early Optical/Ultraviolet Observations with
  94. GRB 050412: retraction of UVOT transient report
  95. GRB 050412: UVOT transient not in XRT error circle
  96. GRB 050412: Swift XRT Position
  97. GRB050412: optical limit before and during GRB
  98. GRB050412: ROTSE-III Optical Limits
  99. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  100. GRB 050412: IR Observations

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