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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. GRB 060114: Swift/UVOT Observations
  2. GRB 060115: MITSuME optical afterglow candidate
  3. GRB 060115: Swift detection of a burst
  4. GRB 060114: Swift XRT upper limit
  5. GRB 060110: KAIT observations
  6. GRB 060111B: Swift XRT refined analysis
  7. GRB 060111A: refined UVOT anaysis
  8. GRB 060111B: TAROT optical observation
  9. GRB060111A: RTT150 optical observations
  10. GRB060111B: RTT150, possible host galaxy
  11. GRB 060111B: Refined analysis of the Swift-BAT burst
  12. GRB 060110: MARGE observations
  13. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  14. GRB 060111B: Swift detection of a burst
  15. GRB 060111: Swift-BAT Refined Analysis
  16. GRB 060111: TAROT optical observation
  17. GRB 060111: possible UVOT counterpart
  18. GRB060111 : XRT refined analysis
  19. GRB 060111: ROTSE-III Optical Limits
  20. GRB 060111: Swift detection of a burst
  21. GRB 060110: Swift-BAT refined analysis
  22. GRB 060109: Swift-BAT refined analysis
  23. GRB 060110a: RAPTOR detection of early optical emission.
  24. Correction to GRB 060109 XRT analysis
  25. GRB 060110: Swift-BAT detection of a burst
  26. GRB 060109: Refined Swift-XRT analysis
  27. GRB 060109: Swift/UVOT upper limits
  28. Swift UVOT correction to GCN 4455
  29. GRB 060109: Swift Detection of a long burst
  30. GRB 060108: Refined XRT analysis
  31. GRB 060108: VLT J-band observations
  32. GRB 060108: Swift/UVOT upper limits
  33. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  34. GRB060108: Faulkes Telescope observation
  35. GRB 060108: Refined analysis of the Swift-BAT burst
  36. GRB 060108: Swift XRT position
  37. GRB060108: Swift detection of its 100th GRB
  38. GRB 060105: Radio observations
  39. Konus-Wind observation of GRB 060105
  40. GRB 060105: Swift/UVOT upper limits
  41. GRB 060105: BAT refined analysis
  42. GRB 060105: XRT refined analysis
  43. GRB060105: Swift detection of a bright long burst
  44. Swift-BAT trigger 175653 is not an astrophysical source
  45. Swift-BAT trigger 175653 is probably not a GRB
  46. GRB 060102: Swift-BAT refined analysis
  47. Time Correction to GRB 060102
  48. GRB 060102: Swift-BAT detection of a burst
  49. GRB051211B: optical observations
  50. GRB051227: SARA Observations
  51. GRB 051221B: Optical Observations with Kuiper 1.54m
  52. GRB051221B: Radio observations
  53. GRB051227: Radio Observations
  54. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  55. GRB 051227: MDM Observation
  56. GRB 051227: Joint Swift-HETE Spectral Analysis
  57. GRB 051227: XRT refined analysis
  58. GRB 051227: Further analysis of the Swift-BAT burst
  59. GRB 051227: Refined analysis of the Swift-BAT burst
  60. GRB051227: SDSS pre-burst observations
  61. GRB 051227: Swift detection of a burst
  62. Konus-Wind observation of GRB 051221A
  63. GRB051221A: Suzaku WAM observation of the prompt emission
  64. GRB051016: analysis of the XMM-Newton observation
  65. GRB 051221A: Detection at 251nm with Swift UVOT
  66. GRB 051221A: Chandra Afterglow Position
  67. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  68. GRB 051221B: ROTSE-III Optical Limits
  69. GRB 051221B: TAROT optical limits
  70. GRB 051221A: WSRT Radio Observations
  71. GRB 051221B: Refined analysis of the Swift-BAT burst
  72. Possible GRB 051221B: MDM Optical Detection
  73. GRB 051221A: RAPTOR Fading Counterpart Constraint
  74. GRB 051221B: BOOTES optical observations.
  75. Possible GRB 051221B: Swift XRT position
  76. Swift-BAT detection of a possible burst
  77. GRB 051221: Swift XRT refined analysis
  78. GRB 051221: Swift/UVOT upper limits
  79. GRB 051221: XRT position
  80. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  81. GRB 051221: Swift detection of a bright short burst
  82. Refined analysis of the SWIFT J1626.6-5156
  83. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  84. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  85. GRB 051211B: optical afterglow
  86. Swift detection of an RS CVn flare star
  87. Swift Trigger 172767 is not a GRB
  88. GRB 051215: Swift detection of a possible burst
  89. GRB 051215: A short GRB in a cluster?
  90. GRB 051213: Swift-BAT refined analysis
  91. GRB051211B: XRT refined analysis
  92. GRB 051213: Swift-BAT detection of a burst
  93. GRB 051211A: Swift/UVOT upper limits
  94. GRB 051211B: Swift/UVOT upper limits - correction
  95. GRB 051211B: Swift/UVOT upper limits
  96. GRB 051211B: Swift XRT confirmation of the afterglow
  97. GRB051211B: Liverpool Telescope observation
  98. GRB 051211B: Swift XRT Observations
  99. GRB 051210: Swift/UVOT upper limits
  100. GRB 051211: Swift XRT upper limit

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