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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').

18348 results found.

  1. GRB 060121: Liverpool Telescopes optical limits
  2. GRB 060121: Swift XRT refined analysis
  3. GRB 060121: Swift XRT refined position
  4. GRB 060117: pseudo-z from spectral parameters of the prompt emission
  5. Konus-Wind observation of GRB 060117
  6. GRB 060117: Refined analysis of the Swift-BAT burst
  7. GRB 060117: FRAM optical afterglow candidate
  8. GRB 060117: Swift-BAT detection of a bright burst
  9. GRB 060116: Refined analysis of the Swift-BAT burst
  10. GRB 060116: Swift/UVOT upper limits
  11. GRB060115: REM observations
  12. GRB 060110: XRT position and analysis
  13. GRB 060116: ROTSE-III Optical Limits
  14. GRB060116: XRT position
  15. GRB060116: Faulkes North observation
  16. GRB 060116: Swift-BAT detection of a burst
  17. GRB 060115: Refined analysis of the Swift-BAT burst
  18. GRB 060115: Swift/UVOT upper limits
  19. GRB 060115: Swift XRT refined analysis
  20. GRB 060114: Swift/UVOT Observations
  21. GRB 060115: MITSuME optical afterglow candidate
  22. GRB 060115: Swift detection of a burst
  23. GRB 060114: Swift XRT upper limit
  24. GRB 060110: KAIT observations
  25. GRB 060111B: Swift XRT refined analysis
  26. GRB 060111A: refined UVOT anaysis
  27. GRB 060111B: TAROT optical observation
  28. GRB060111A: RTT150 optical observations
  29. GRB060111B: RTT150, possible host galaxy
  30. GRB 060111B: Refined analysis of the Swift-BAT burst
  31. GRB 060110: MARGE observations
  32. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  33. GRB 060111B: Swift detection of a burst
  34. GRB 060111: Swift-BAT Refined Analysis
  35. GRB 060111: TAROT optical observation
  36. GRB 060111: possible UVOT counterpart
  37. GRB060111 : XRT refined analysis
  38. GRB 060111: ROTSE-III Optical Limits
  39. GRB 060111: Swift detection of a burst
  40. GRB 060110: Swift-BAT refined analysis
  41. GRB 060109: Swift-BAT refined analysis
  42. GRB 060110a: RAPTOR detection of early optical emission.
  43. Correction to GRB 060109 XRT analysis
  44. GRB 060110: Swift-BAT detection of a burst
  45. GRB 060109: Refined Swift-XRT analysis
  46. GRB 060109: Swift/UVOT upper limits
  47. Swift UVOT correction to GCN 4455
  48. GRB 060109: Swift Detection of a long burst
  49. GRB 060108: Refined XRT analysis
  50. GRB 060108: VLT J-band observations
  51. GRB 060108: Swift/UVOT upper limits
  52. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  53. GRB060108: Faulkes Telescope observation
  54. GRB 060108: Refined analysis of the Swift-BAT burst
  55. GRB 060108: Swift XRT position
  56. GRB060108: Swift detection of its 100th GRB
  57. GRB 060105: Radio observations
  58. Konus-Wind observation of GRB 060105
  59. GRB 060105: Swift/UVOT upper limits
  60. GRB 060105: BAT refined analysis
  61. GRB 060105: XRT refined analysis
  62. GRB060105: Swift detection of a bright long burst
  63. Swift-BAT trigger 175653 is not an astrophysical source
  64. Swift-BAT trigger 175653 is probably not a GRB
  65. GRB 060102: Swift-BAT refined analysis
  66. Time Correction to GRB 060102
  67. GRB 060102: Swift-BAT detection of a burst
  68. GRB051211B: optical observations
  69. GRB051227: SARA Observations
  70. GRB 051221B: Optical Observations with Kuiper 1.54m
  71. GRB051221B: Radio observations
  72. GRB051227: Radio Observations
  73. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  74. GRB 051227: MDM Observation
  75. GRB 051227: Joint Swift-HETE Spectral Analysis
  76. GRB 051227: XRT refined analysis
  77. GRB 051227: Further analysis of the Swift-BAT burst
  78. GRB 051227: Refined analysis of the Swift-BAT burst
  79. GRB051227: SDSS pre-burst observations
  80. GRB 051227: Swift detection of a burst
  81. Konus-Wind observation of GRB 051221A
  82. GRB051221A: Suzaku WAM observation of the prompt emission
  83. GRB051016: analysis of the XMM-Newton observation
  84. GRB 051221A: Detection at 251nm with Swift UVOT
  85. GRB 051221A: Chandra Afterglow Position
  86. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  87. GRB 051221B: ROTSE-III Optical Limits
  88. GRB 051221B: TAROT optical limits
  89. GRB 051221A: WSRT Radio Observations
  90. GRB 051221B: Refined analysis of the Swift-BAT burst
  91. Possible GRB 051221B: MDM Optical Detection
  92. GRB 051221A: RAPTOR Fading Counterpart Constraint
  93. GRB 051221B: BOOTES optical observations.
  94. Possible GRB 051221B: Swift XRT position
  95. Swift-BAT detection of a possible burst
  96. GRB 051221: Swift XRT refined analysis
  97. GRB 051221: Swift/UVOT upper limits
  98. GRB 051221: XRT position
  99. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  100. GRB 051221: Swift detection of a bright short burst

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