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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').

17954 results found.

  1. GRB 050421: SLOTIS observations
  2. GRB050421: Radio Observations
  3. GRB050421: Radio Observations
  4. GRB 050421: Swift-UVOT observation
  5. GRB 050421: Swift-BAT refined analysis
  6. GRB 050421: ROTSE-III Optical Limits
  7. GRB 050421: early Swift XRT analysis results
  8. GRB 050421: BOOTES-2 simultaneous optical observations
  9. GRB 050421: Optical observations at the INT
  10. Swift Detection of GRB050421
  11. GRB 050416b: Tentative Swift XRT Position
  12. GRB050326: analysis of the XMM-Newton observation
  13. GRB 050418: Swift-BAT refined analysis
  14. Swift-BAT detection of the bright and long GRB 050418
  15. GRB 050416B: optical observations
  16. GRB 050416b: Swift-BAT refined analysis
  17. GRB 050416: Swift/UVOT refined analysis
  18. Swift-BAT detection of GRB 050416b
  19. GRB050412: Radio Observations
  20. GRB 050416: Swift/UVOT detection of afterglow emission
  21. GRB050416: Refined Swift-XRT analysis
  22. GRB050416: Maidanak optical observations
  23. GRB 050416: Swift-BAT refined analysis
  24. GRB 050416,optical observation
  25. GRB 050416: KAIT observations
  26. GRB 050416: Swift XRT Position
  27. GRB 050416: Radio observations
  28. Confirmation of OT for GRB050416
  29. GRB050416: P60 Afterglow Candidate
  30. Swift BAT/XRT Detection of GRB 050416
  31. GRB 050412: Subaru observations
  32. GRB 050412: optical limit
  33. GRB 050412: optical observations
  34. GRB 050408: refined XRT analysis, no jet break seen yet
  35. GRB 050412: early Swift XRT analysis results
  36. GRB 050412: Swift-BAT refined analysis
  37. GRB 050412: ANU 2.3m observations
  38. GRB 050412: Early Optical/Ultraviolet Observations with
  39. GRB 050412: retraction of UVOT transient report
  40. GRB 050412: UVOT transient not in XRT error circle
  41. GRB 050412: Swift XRT Position
  42. GRB050412: optical limit before and during GRB
  43. GRB050412: ROTSE-III Optical Limits
  44. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  45. GRB 050412: IR Observations
  46. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  47. GRB 050410, optical observations
  48. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  49. GRB 050410 R band Optical Observations
  50. GRB050410 : Null detection report
  51. GRB 050410, optical observations
  52. GRB050410: Radio Observations
  53. GRB 050408: Swift XRT measurement of possible jet break
  54. GRB050410: MASTER optical observations
  55. GRB 050410: Early observations with Swift-UVOT
  56. Swift-BAT detection of GRB 050410
  57. GRB 050410: Swift XRT Position
  58. GRB 050408: Properties of the Host Galaxy
  59. GRB 050408: Swift XRT analysis
  60. GRB 050408, optical observations
  61. GRB050408: REM NIR and Optical observation
  62. GRB 050408 Optical Observations
  63. GRB 050408: Optical afterglow confirmed
  64. GRB 050408, optical observations
  65. GRB 050408 optical candidate
  66. GRB 050408: Swift XRT Position
  67. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  68. GRB 050406: early Swift XRT analysis results
  69. GRB 050406 BAT refined analysis
  70. GRB 050406: Early observations with Swift-UVOT
  71. GRB 050406: Swift XRT Position
  72. Swift-BAT detection of GRB 050406
  73. Konus-Wind observation of GRB 050401
  74. GRB050401: Radio observation at 610 MHz with GMRT
  75. GRB 050401: VLT spectroscopic redshift
  76. GRB 050401 Optical Observations
  77. GRB050401: Maidanak optical observation
  78. GRB 050401 BAT refined analysis
  79. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  80. GRB 050402A: IR Observations
  81. GRB 050402: Early observations with Swift-UVOT
  82. Swift Trigger 113225: P60 Observations
  83. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  84. GRB 050401: Optical afterglow candidate
  85. Swift-BAT detection of GRB 050401
  86. GRB 050401: Prompt XRT position
  87. Retraction of three Swift GRB triggers
  88. Swift-BAT detection of GRB 050331b
  89. GRB 050331: Swift UVOT Source
  90. Swift-BAT detection of GRB 050331
  91. GRB 050331: Swift XRT Position
  92. Swift Data Publicly Available Starting April 5, 2005
  93. Konus-Wind observation of GRB 050326
  94. GRB050326: optical limit
  95. GRB 050326: Early observations with Swift-UVOT
  96. GRB 050326 XMM-Newton observation
  97. GRB 050326 : Planned XMM-Newton observation
  98. GRB 050326: Swift XRT Position
  99. GRB050326: optical limit 33min before GRB
  100. GRB 050326 BAT refined analysis

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