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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').

18282 results found.

  1. GRB 051001: ROTSE-III Optical Limits
  2. GRB050922B: optical limit
  3. GRB050925: Swift/XRT limits
  4. GRB/SGR 050925: IR Observations
  5. GRB050922C - Swift UVOT preliminary analysis
  6. GRB 050925: WSRT Radio Observations
  7. GRB050925: Swift UVOT upper limits
  8. Refined analysis of the Swift-BAT soft short burst
  9. GRB050925: Faulkes Telescope North R-band limit
  10. GRB050925: Swift-BAT detection of a short burst
  11. GRB 050922B: Correction to BAT refined analysis, longer burst
  12. GRB050922B: refined XRT analysis
  13. Konus-Wind observation of GRB 050922C
  14. GRB050922B: Swift UVOT early upper limits.
  15. GRB 050922B: optical limit
  16. GRB 050922C: Swift XRT refined analysis
  17. HETE Fregate observations of GRB 050922C
  18. GRB 050922C: Swift-BAT refined analysis
  19. GRB 050922B: Swift-BAT refined analysis
  20. GRB050922C: optical observations
  21. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  22. GRB 050922C: optical obserations
  23. GRB 050922C: NOT optical observations
  24. GRB 050922A: Analysis of Swift/XRT TOO observation
  25. GRB 050922C: Swift detection of a bright burst
  26. GRB 050922C: ROTSE-IIId Refined Analysis
  27. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  28. GRB 050922B: ROTSE-III Optical Limits
  29. GRB 050922B,optical observation
  30. GRB050922B: Swift-BAT detection of a weak long burst
  31. GRB050918: Possible Swift/XRT detected afterglow
  32. GRB050820B: analysis of the XMM-Newton observation
  33. GRB050916: Swift/UVOT Upper Limits
  34. GRB 050916: Swift-BAT refined analysis
  35. Swift-BAT trigger 155764 is not a GRB
  36. Swift-BAT trigger 155764 is probably not a GRB
  37. Swift trigger 155764: bad XRT centroid
  38. Swift-BAT trigger 155535 is definitely not a GRB
  39. GRB050916 : Swift-XRT refined analysis
  40. GRB 050916: XRT position
  41. GRB 050915B: Swift-BAT refined analysis
  42. GRB 050915B: Swift/UVOT Upper Limits
  43. GRB050916: Swift-BAT detection of a long weak burst
  44. GRB 050915B: XRT position
  45. GRB050915B: Swift-BAT detection of a long bright burst
  46. GRB050915: Swift/UVOT upper limits
  47. GRB 050915: KAIT optical limit
  48. GRB 050915: IR Observations
  49. GRB 050915: Swift XRT refined analysis
  50. GRB 050915: Swift-BAT refined analysis
  51. GRB050915, optical observations
  52. GRB050915: XRT position
  53. GRB 050915: ROTSE-III optical limits
  54. GRB 050915: Swift detection of a GRB
  55. GRB050911: Upper limit on X-ray afterglow
  56. Swift-BAT trigger 155072 ground analysis
  57. Swift-BAT trigger 155072 is probably not a GRB
  58. GRB050914: XRT position probably due to cosmic ray
  59. Swift is in normal operation
  60. GRB050911: Swift UVOT followup observations
  61. GRB 050911, optical content of Swift/XRT error box
  62. GRB050911: Swift-XRT position
  63. GRB 050911, optical observations
  64. GRB 050911: Swift-BAT refined analysis
  65. Later Swift-BAT triggers 154632 and 154633 RETRACTION
  66. GRB050911: Swift-BAT detection of a long burst
  67. GRB050908: detection of Swift/UVOT optical counterpart
  68. RBO GRB 050908 observations
  69. WIRO observations in I of GRB 050908
  70. GRB 050906: Possible X-ray Counterpart
  71. GRB050908: Swift/UVOT Early upper limits
  72. GRB050908 : Swift-XRT refined analysis
  73. GRB 050908: Swift-BAT refined analysis
  74. GRB 050908: Optical observations
  75. Gemini Spectroscopy of GRB 050908
  76. GRB 050908 : Swift XRT position
  77. GRB 050908: KAIT observations
  78. GRB 050908: P60 Confirmation of Optical Afterglow
  79. GRB 050908: Swift detection of a burst
  80. Swift trigger 154073 is not a GRB
  81. GRB050904: CrAO optical observations
  82. GRB 050904 BAT refined analysis of complete data set
  83. GRB 050906: MARGE Optical Limits
  84. GRB 050906: Swift-BAT refined analysis
  85. GRB 050906: Swift XRT upper limit
  86. GRB050906: P60 Observations
  87. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  88. GRB 050906: Bright galaxy in BAT error box
  89. GRB 050906: Swift/BAT Detection of a possible burst
  90. GRB 050904: Swift/UVOT observations
  91. GRB 050904: early Swift XRT analysis results
  92. GRB 050904: BAT refined analysis of partial data set
  93. GRB050904: P60 Observations
  94. GRB 050904: TAROT optical limits
  95. GRB050904: Swift-BAT detection of a probable burst
  96. Swift-BAT triggers 153461-153465 are not GRBs
  97. Retraction of Swift-BAT trigger #153355
  98. GRB 050824: MDM Observations
  99. GRB 050827: Swift XRT preliminary analysis results
  100. Swift Trigger #152652 is not a GRB

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