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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').

18311 results found.

  1. GRB060111 : XRT refined analysis
  2. GRB 060111: ROTSE-III Optical Limits
  3. GRB 060111: Swift detection of a burst
  4. GRB 060110: Swift-BAT refined analysis
  5. GRB 060109: Swift-BAT refined analysis
  6. GRB 060110a: RAPTOR detection of early optical emission.
  7. Correction to GRB 060109 XRT analysis
  8. GRB 060110: Swift-BAT detection of a burst
  9. GRB 060109: Refined Swift-XRT analysis
  10. GRB 060109: Swift/UVOT upper limits
  11. Swift UVOT correction to GCN 4455
  12. GRB 060109: Swift Detection of a long burst
  13. GRB 060108: Refined XRT analysis
  14. GRB 060108: VLT J-band observations
  15. GRB 060108: Swift/UVOT upper limits
  16. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  17. GRB060108: Faulkes Telescope observation
  18. GRB 060108: Refined analysis of the Swift-BAT burst
  19. GRB 060108: Swift XRT position
  20. GRB060108: Swift detection of its 100th GRB
  21. GRB 060105: Radio observations
  22. Konus-Wind observation of GRB 060105
  23. GRB 060105: Swift/UVOT upper limits
  24. GRB 060105: BAT refined analysis
  25. GRB 060105: XRT refined analysis
  26. GRB060105: Swift detection of a bright long burst
  27. Swift-BAT trigger 175653 is not an astrophysical source
  28. Swift-BAT trigger 175653 is probably not a GRB
  29. GRB 060102: Swift-BAT refined analysis
  30. Time Correction to GRB 060102
  31. GRB 060102: Swift-BAT detection of a burst
  32. GRB051211B: optical observations
  33. GRB051227: SARA Observations
  34. GRB 051221B: Optical Observations with Kuiper 1.54m
  35. GRB051221B: Radio observations
  36. GRB051227: Radio Observations
  37. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  38. GRB 051227: MDM Observation
  39. GRB 051227: Joint Swift-HETE Spectral Analysis
  40. GRB 051227: XRT refined analysis
  41. GRB 051227: Further analysis of the Swift-BAT burst
  42. GRB 051227: Refined analysis of the Swift-BAT burst
  43. GRB051227: SDSS pre-burst observations
  44. GRB 051227: Swift detection of a burst
  45. Konus-Wind observation of GRB 051221A
  46. GRB051221A: Suzaku WAM observation of the prompt emission
  47. GRB051016: analysis of the XMM-Newton observation
  48. GRB 051221A: Detection at 251nm with Swift UVOT
  49. GRB 051221A: Chandra Afterglow Position
  50. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  51. GRB 051221B: ROTSE-III Optical Limits
  52. GRB 051221B: TAROT optical limits
  53. GRB 051221A: WSRT Radio Observations
  54. GRB 051221B: Refined analysis of the Swift-BAT burst
  55. Possible GRB 051221B: MDM Optical Detection
  56. GRB 051221A: RAPTOR Fading Counterpart Constraint
  57. GRB 051221B: BOOTES optical observations.
  58. Possible GRB 051221B: Swift XRT position
  59. Swift-BAT detection of a possible burst
  60. GRB 051221: Swift XRT refined analysis
  61. GRB 051221: Swift/UVOT upper limits
  62. GRB 051221: XRT position
  63. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  64. GRB 051221: Swift detection of a bright short burst
  65. Refined analysis of the SWIFT J1626.6-5156
  66. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  67. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  68. GRB 051211B: optical afterglow
  69. Swift detection of an RS CVn flare star
  70. Swift Trigger 172767 is not a GRB
  71. GRB 051215: Swift detection of a possible burst
  72. GRB 051215: A short GRB in a cluster?
  73. GRB 051213: Swift-BAT refined analysis
  74. GRB051211B: XRT refined analysis
  75. GRB 051213: Swift-BAT detection of a burst
  76. GRB 051211A: Swift/UVOT upper limits
  77. GRB 051211B: Swift/UVOT upper limits - correction
  78. GRB 051211B: Swift/UVOT upper limits
  79. GRB 051211B: Swift XRT confirmation of the afterglow
  80. GRB051211B: Liverpool Telescope observation
  81. GRB 051211B: Swift XRT Observations
  82. GRB 051210: Swift/UVOT upper limits
  83. GRB 051211: Swift XRT upper limit
  84. GRB 051210: SALT detection limit
  85. GRB 051210: BAT further refined analysis of the short burst
  86. GRB 051210: Swift XRT refined analysis
  87. GRB 051210: Swift-BAT refined analysis of a short burst
  88. GRB051210: Swift UVOT Observation
  89. GRB 051210: Swift detection of a burst
  90. IPN observations of SGR1806-20
  91. Swift XRT positions
  92. An extraordinary long burst on December 3 from SGR1806-20
  93. Swift UVOT Calibration Documentation
  94. Swift-BAT trigger 165579 is not a GRB
  95. GRB 051127: Swift-BAT detection of a possible burst
  96. GRB051117B: Swift XRT refined analysis
  97. GRB051117b: No Swift/UVOT Detection
  98. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  99. GRB 051117A: Swift/UVOT Detection of an Afterglow
  100. GRB051111: Rc optical observations

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