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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. GRB050911: Upper limit on X-ray afterglow
  2. Swift-BAT trigger 155072 ground analysis
  3. Swift-BAT trigger 155072 is probably not a GRB
  4. GRB050914: XRT position probably due to cosmic ray
  5. Swift is in normal operation
  6. GRB050911: Swift UVOT followup observations
  7. GRB 050911, optical content of Swift/XRT error box
  8. GRB050911: Swift-XRT position
  9. GRB 050911, optical observations
  10. GRB 050911: Swift-BAT refined analysis
  11. Later Swift-BAT triggers 154632 and 154633 RETRACTION
  12. GRB050911: Swift-BAT detection of a long burst
  13. GRB050908: detection of Swift/UVOT optical counterpart
  14. RBO GRB 050908 observations
  15. WIRO observations in I of GRB 050908
  16. GRB 050906: Possible X-ray Counterpart
  17. GRB050908: Swift/UVOT Early upper limits
  18. GRB050908 : Swift-XRT refined analysis
  19. GRB 050908: Swift-BAT refined analysis
  20. GRB 050908: Optical observations
  21. Gemini Spectroscopy of GRB 050908
  22. GRB 050908 : Swift XRT position
  23. GRB 050908: KAIT observations
  24. GRB 050908: P60 Confirmation of Optical Afterglow
  25. GRB 050908: Swift detection of a burst
  26. Swift trigger 154073 is not a GRB
  27. GRB050904: CrAO optical observations
  28. GRB 050904 BAT refined analysis of complete data set
  29. GRB 050906: MARGE Optical Limits
  30. GRB 050906: Swift-BAT refined analysis
  31. GRB 050906: Swift XRT upper limit
  32. GRB050906: P60 Observations
  33. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  34. GRB 050906: Bright galaxy in BAT error box
  35. GRB 050906: Swift/BAT Detection of a possible burst
  36. GRB 050904: Swift/UVOT observations
  37. GRB 050904: early Swift XRT analysis results
  38. GRB 050904: BAT refined analysis of partial data set
  39. GRB050904: P60 Observations
  40. GRB 050904: TAROT optical limits
  41. GRB050904: Swift-BAT detection of a probable burst
  42. Swift-BAT triggers 153461-153465 are not GRBs
  43. Retraction of Swift-BAT trigger #153355
  44. GRB 050824: MDM Observations
  45. GRB 050827: Swift XRT preliminary analysis results
  46. Swift Trigger #152652 is not a GRB
  47. GRB050827: Swift/UVOT upper limits
  48. GRB 050827: Optical Limit
  49. GRB 050827: XRT possible afterglow detection
  50. GRB050827: RTT150 optical observations
  51. GRB 050827: Swift-BAT refined analysis
  52. GRB050827: Swift-BAT detection of a burst
  53. GRB 050826: Optical Candidate
  54. GRB050824, HETE-2 Observation
  55. GRB 050826: Swift XRT preliminary analysis results
  56. GRB 050826: BAT refined analysis
  57. GRB050826: Swift/UVOT early upper limits
  58. GRB050824: First 2 hours of power low optical decay?
  59. GRB 050826: Swift XRT position
  60. GRB050826: Swift-BAT detection of a long burst
  61. GRB050824: MASTER final analysis of the OT observations
  62. Possible GRB050825:MASTER optical observations
  63. Swift-BAT trigger 152038 is definitely not a GRB
  64. GRB050824: CORRECTION to UVOT observing times
  65. Swift-BAT trigger 152038 is probably not a GRB
  66. GRB050824: Swift/UVOT detection of fading afterglow
  67. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  68. GRB050824, I-band imaging
  69. GRB 050822: refined XRT analysis
  70. GRB 050824: XRT refined analysis and possible afterglow detection
  71. GRB 050824: BAT refined analysis of a soft weak burst
  72. GRB050824: MASTER:OT decay
  73. GRB050824: MASTER observation OT
  74. GRB050805a: MASTER optical candidat
  75. GRB 050824: ROTSE-III Optical Limits
  76. GRB050824: Swift-BAT detection of a burst
  77. GRB050822: Swift/UVOT upper limits
  78. GRB 050820A BAT observations of second, larger episode of emission
  79. GRB 050822: Swift-BAT refined analysis
  80. GRB 050820a - corrections to GCN 3846
  81. Swift/UVOT UV Photometry of GRB 050820B
  82. GRB 050822: ROTSE-III Prompt Optical Limits
  83. GRB 050822: Swift detection of a long burst
  84. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  85. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  86. GRB050820a BVRcIc field photometry
  87. GRB050820B XMM-Newton observation
  88. GRB 050820a: NIR Observations by WIRO
  89. GRB 050820B: Swift XRT position
  90. SUBJECT: GRB050820B: Refined analysis of the Swift-BAT burst
  91. GRB050820B: BAT-Swift detection of a bright GRB
  92. Swift/UVOT photometry of GRB050820
  93. GRB050820: refined XRT analysis
  94. GRB 050820: Early RAPTOR detections
  95. GRB 050820 Swift-BAT refined analysis
  96. GRB050819: refined XRT analysis
  97. GRB 050820: Swift detection of a GRB
  98. GRB050820: Optical afterglow from P60
  99. GRB 050819 Swift-BAT refined analysis
  100. GRB050819: Swift XRT position

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