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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').

17828 results found.

  1. Confirmation of OT for GRB050416
  2. GRB050416: P60 Afterglow Candidate
  3. Swift BAT/XRT Detection of GRB 050416
  4. GRB 050412: Subaru observations
  5. GRB 050412: optical limit
  6. GRB 050412: optical observations
  7. GRB 050408: refined XRT analysis, no jet break seen yet
  8. GRB 050412: early Swift XRT analysis results
  9. GRB 050412: Swift-BAT refined analysis
  10. GRB 050412: ANU 2.3m observations
  11. GRB 050412: Early Optical/Ultraviolet Observations with
  12. GRB 050412: retraction of UVOT transient report
  13. GRB 050412: UVOT transient not in XRT error circle
  14. GRB 050412: Swift XRT Position
  15. GRB050412: optical limit before and during GRB
  16. GRB050412: ROTSE-III Optical Limits
  17. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  18. GRB 050412: IR Observations
  19. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  20. GRB 050410, optical observations
  21. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  22. GRB 050410 R band Optical Observations
  23. GRB050410 : Null detection report
  24. GRB 050410, optical observations
  25. GRB050410: Radio Observations
  26. GRB 050408: Swift XRT measurement of possible jet break
  27. GRB050410: MASTER optical observations
  28. GRB 050410: Early observations with Swift-UVOT
  29. Swift-BAT detection of GRB 050410
  30. GRB 050410: Swift XRT Position
  31. GRB 050408: Properties of the Host Galaxy
  32. GRB 050408: Swift XRT analysis
  33. GRB 050408, optical observations
  34. GRB050408: REM NIR and Optical observation
  35. GRB 050408 Optical Observations
  36. GRB 050408: Optical afterglow confirmed
  37. GRB 050408, optical observations
  38. GRB 050408 optical candidate
  39. GRB 050408: Swift XRT Position
  40. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  41. GRB 050406: early Swift XRT analysis results
  42. GRB 050406 BAT refined analysis
  43. GRB 050406: Early observations with Swift-UVOT
  44. GRB 050406: Swift XRT Position
  45. Swift-BAT detection of GRB 050406
  46. Konus-Wind observation of GRB 050401
  47. GRB050401: Radio observation at 610 MHz with GMRT
  48. GRB 050401: VLT spectroscopic redshift
  49. GRB 050401 Optical Observations
  50. GRB050401: Maidanak optical observation
  51. GRB 050401 BAT refined analysis
  52. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  53. GRB 050402A: IR Observations
  54. GRB 050402: Early observations with Swift-UVOT
  55. Swift Trigger 113225: P60 Observations
  56. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  57. GRB 050401: Optical afterglow candidate
  58. Swift-BAT detection of GRB 050401
  59. GRB 050401: Prompt XRT position
  60. Retraction of three Swift GRB triggers
  61. Swift-BAT detection of GRB 050331b
  62. GRB 050331: Swift UVOT Source
  63. Swift-BAT detection of GRB 050331
  64. GRB 050331: Swift XRT Position
  65. Swift Data Publicly Available Starting April 5, 2005
  66. Konus-Wind observation of GRB 050326
  67. GRB050326: optical limit
  68. GRB 050326: Early observations with Swift-UVOT
  69. GRB 050326 XMM-Newton observation
  70. GRB 050326 : Planned XMM-Newton observation
  71. GRB 050326: Swift XRT Position
  72. GRB050326: optical limit 33min before GRB
  73. GRB 050326 BAT refined analysis
  74. GRB050326: delayed XRT observation
  75. Swift-BAT detection of a bright GRB 050326
  76. GRB050319, optical observations
  77. GRB050319, color indices
  78. GRB050319: RTT150 Optical Observations
  79. Swift-BAT detection of a bright outburst from SGR1806-20
  80. Swift-BAT trigger 112060 is not a real GRB
  81. GRB 050319: ROTSE-III Refined Analysis
  82. GRB 050318: Swift-BAT refined analysis
  83. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  84. GRB 050319 R band observations
  85. GRB 050319: Swift-UVOT detection of the afterglow
  86. GRB 050315: Variability Analysis of Swift BAT Time History
  87. GRB050319: BR optical photometry
  88. GRB 050318: SWIFT-UVOT refined analysis
  89. GRB 050319: Swift-BAT refined analysis
  90. GRB050319,optical observation
  91. Swift Detection of GRB 050319
  92. GRB 050319: Detection of Possible Optical Counterpart
  93. GRB 050318: Swift/UVOT detection of afterglow emission
  94. GRB050318: Swift XRT position
  95. Swift-BAT detection of GRB 050318
  96. GRB050223: analysis of the XMM-Newton observation
  97. GRB 050306: ROTSE-III early limits
  98. GRB 050315: Swift-BAT further refined analysis
  99. GRB050315: Swift-BAT Refined analysis
  100. Non-detection of GRB050315 in ATCA Radio Observations

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