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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').

10045 results found.

  1. GRB 050421: early Swift XRT analysis results
  2. GRB 050421: BOOTES-2 simultaneous optical observations
  3. Swift Detection of GRB050421
  4. GRB 050416b: Tentative Swift XRT Position
  5. GRB050418: Null Optical Observations
  6. GRB 050418: Swift-BAT refined analysis
  7. Swift-BAT detection of the bright and long GRB 050418
  8. GRB 050416: Mitsume optical observation
  9. GRB 050416b: Swift-BAT refined analysis
  10. GRB 050416b: LCO observations
  11. GRB 050416b: LCO observations
  12. GRB 050416: Swift/UVOT refined analysis
  13. Swift-BAT detection of GRB 050416b
  14. IBAS GRB Alert # 2463: not a GRB
  15. GRB 050416: Swift/UVOT detection of afterglow emission
  16. GRB050416: Refined Swift-XRT analysis
  17. GRB 050416: Swift-BAT refined analysis
  18. GRB 050416: Swift XRT Position
  19. Swift BAT/XRT Detection of GRB 050416
  20. GRB 050412: Subaru observations
  21. GRB 050408: RTT150 optical observations
  22. GRB 050408: refined XRT analysis, no jet break seen yet
  23. GRB 050412: Swift-BAT refined analysis
  24. GRB 050412: Early Optical/Ultraviolet Observations with
  25. GRB 050412: Swift XRT Position
  26. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  27. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  28. GRB 050410, optical observations
  29. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  30. GRB 050408: Swift XRT measurement of possible jet break
  31. GRB 050410: Early observations with Swift-UVOT
  32. Swift-BAT detection of GRB 050410
  33. GRB 050410: Swift XRT Position
  34. GRB 050408: Inconsistency of host galaxy identification
  35. GRB 050408: Subaru Observations
  36. GRB 050408: Swift XRT analysis
  37. GRB 050408, optical observations
  38. GRB 050408: First Optical observations with TFOSC at the RTT150
  39. GRB 050408: opitcal observation
  40. GRB 050408: Swift XRT Position
  41. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  42. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  43. GRB 050406: early Swift XRT analysis results
  44. GRB 050406 BAT refined analysis
  45. GRB 050406: Early observations with Swift-UVOT
  46. GRB 050406: Swift XRT Position
  47. Swift-BAT detection of GRB 050406
  48. GRB 050401 BAT refined analysis
  49. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  50. GRB050401: TNG R-band observation
  51. GRB050402: XDSS counterpart
  52. GRB 050402: Early observations with Swift-UVOT
  53. Swift-BAT detection of GRB 050401
  54. GRB 050401: Prompt XRT position
  55. Retraction of three Swift GRB triggers
  56. GRB050331: No Afterglow Detected
  57. Swift-BAT detection of GRB 050331b
  58. GRB 050331: Swift UVOT Source
  59. Swift-BAT detection of GRB 050331
  60. GRB 050331: Swift XRT Position
  61. GRB 050326: Early observations with Swift-UVOT
  62. GRB 050326: Swift XRT Position
  63. GRB 050326 BAT refined analysis
  64. GRB050326: delayed XRT observation
  65. Swift-BAT detection of a bright GRB 050326
  66. GRB050319, color indices
  67. Swift-BAT detection of a bright outburst from SGR1806-20
  68. Swift-BAT trigger 112060 is not a real GRB
  69. GRB 050319: Absorption redshift from the Nordic Optical Telescope
  70. GRB 050318: Swift-BAT refined analysis
  71. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  72. GRB 050319: Swift-UVOT detection of the afterglow
  73. GRB 050318: SWIFT-UVOT refined analysis
  74. GRB 050319: Swift-BAT refined analysis
  75. Swift Detection of GRB 050319
  76. GRB 050318: Swift/UVOT detection of afterglow emission
  77. GRB050318: Swift XRT position
  78. RXTE Observations of GRB050318
  79. Swift-BAT detection of GRB 050318
  80. GRB 050315: Swift-BAT further refined analysis
  81. GRB050315: Swift-BAT Refined analysis
  82. GRB 050315: Swift XRT Position
  83. GRB 050315: Early Observations with Swift/UVOT
  84. Swift-BAT detection of GRB 050315
  85. GRB050223: No XMM-Newton OM detection of afterglow emission
  86. GRB 050306: optical afterglow
  87. Swift-BAT trigger 107873: No Swift XRT counterpart
  88. GRB 050306: Confirmation of X-ray afterglow
  89. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  90. GRB 050309 : Lulin R-band observation
  91. GRB 050306: CORRECTION to date of observation
  92. GRB 050306: R-band observations
  93. GRB 050306: No Swift UVOT Optical Counterpart Detected
  94. GRB 050306: REM optical-infrared observations
  95. GRB 050306: Possible X-ray Afterglow Position from the Swift
  96. GRB 050306: Swift-BAT detection of a long burst
  97. GRB050215B: Late-Time Swift UVOT Observations
  98. Confirmed XRF nature for GRB050215b
  99. INTEGRAL detection of GRB 050223
  100. GRB050223: No Swift UVOT Detection of Afterglow Emission

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