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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').

18345 results found.

  1. GRB050326: analysis of the XMM-Newton observation
  2. GRB 050418: Swift-BAT refined analysis
  3. Swift-BAT detection of the bright and long GRB 050418
  4. GRB 050416B: optical observations
  5. GRB 050416b: Swift-BAT refined analysis
  6. GRB 050416: Swift/UVOT refined analysis
  7. Swift-BAT detection of GRB 050416b
  8. GRB050412: Radio Observations
  9. GRB 050416: Swift/UVOT detection of afterglow emission
  10. GRB050416: Refined Swift-XRT analysis
  11. GRB050416: Maidanak optical observations
  12. GRB 050416: Swift-BAT refined analysis
  13. GRB 050416,optical observation
  14. GRB 050416: KAIT observations
  15. GRB 050416: Swift XRT Position
  16. GRB 050416: Radio observations
  17. Confirmation of OT for GRB050416
  18. GRB050416: P60 Afterglow Candidate
  19. Swift BAT/XRT Detection of GRB 050416
  20. GRB 050412: Subaru observations
  21. GRB 050412: optical limit
  22. GRB 050412: optical observations
  23. GRB 050408: refined XRT analysis, no jet break seen yet
  24. GRB 050412: early Swift XRT analysis results
  25. GRB 050412: Swift-BAT refined analysis
  26. GRB 050412: ANU 2.3m observations
  27. GRB 050412: Early Optical/Ultraviolet Observations with
  28. GRB 050412: retraction of UVOT transient report
  29. GRB 050412: UVOT transient not in XRT error circle
  30. GRB 050412: Swift XRT Position
  31. GRB050412: optical limit before and during GRB
  32. GRB050412: ROTSE-III Optical Limits
  33. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  34. GRB 050412: IR Observations
  35. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  36. GRB 050410, optical observations
  37. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  38. GRB 050410 R band Optical Observations
  39. GRB050410 : Null detection report
  40. GRB 050410, optical observations
  41. GRB050410: Radio Observations
  42. GRB 050408: Swift XRT measurement of possible jet break
  43. GRB050410: MASTER optical observations
  44. GRB 050410: Early observations with Swift-UVOT
  45. Swift-BAT detection of GRB 050410
  46. GRB 050410: Swift XRT Position
  47. GRB 050408: Properties of the Host Galaxy
  48. GRB 050408: Swift XRT analysis
  49. GRB 050408, optical observations
  50. GRB050408: REM NIR and Optical observation
  51. GRB 050408 Optical Observations
  52. GRB 050408: Optical afterglow confirmed
  53. GRB 050408, optical observations
  54. GRB 050408 optical candidate
  55. GRB 050408: Swift XRT Position
  56. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  57. GRB 050406: early Swift XRT analysis results
  58. GRB 050406 BAT refined analysis
  59. GRB 050406: Early observations with Swift-UVOT
  60. GRB 050406: Swift XRT Position
  61. Swift-BAT detection of GRB 050406
  62. Konus-Wind observation of GRB 050401
  63. GRB050401: Radio observation at 610 MHz with GMRT
  64. GRB 050401: VLT spectroscopic redshift
  65. GRB 050401 Optical Observations
  66. GRB050401: Maidanak optical observation
  67. GRB 050401 BAT refined analysis
  68. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  69. GRB 050402A: IR Observations
  70. GRB 050402: Early observations with Swift-UVOT
  71. Swift Trigger 113225: P60 Observations
  72. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  73. GRB 050401: Optical afterglow candidate
  74. Swift-BAT detection of GRB 050401
  75. GRB 050401: Prompt XRT position
  76. Retraction of three Swift GRB triggers
  77. Swift-BAT detection of GRB 050331b
  78. GRB 050331: Swift UVOT Source
  79. Swift-BAT detection of GRB 050331
  80. GRB 050331: Swift XRT Position
  81. Swift Data Publicly Available Starting April 5, 2005
  82. Konus-Wind observation of GRB 050326
  83. GRB050326: optical limit
  84. GRB 050326: Early observations with Swift-UVOT
  85. GRB 050326 XMM-Newton observation
  86. GRB 050326 : Planned XMM-Newton observation
  87. GRB 050326: Swift XRT Position
  88. GRB050326: optical limit 33min before GRB
  89. GRB 050326 BAT refined analysis
  90. GRB050326: delayed XRT observation
  91. Swift-BAT detection of a bright GRB 050326
  92. GRB050319, optical observations
  93. GRB050319, color indices
  94. GRB050319: RTT150 Optical Observations
  95. Swift-BAT detection of a bright outburst from SGR1806-20
  96. Swift-BAT trigger 112060 is not a real GRB
  97. GRB 050319: ROTSE-III Refined Analysis
  98. GRB 050318: Swift-BAT refined analysis
  99. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  100. GRB 050319 R band observations

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