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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21466 results found.

  1. GRB 060111: ROTSE-III Optical Limits
  2. GRB 060111: Swift detection of a burst
  3. GRB 060110: Swift-BAT refined analysis
  4. GRB 060109: Swift-BAT refined analysis
  5. GRB 060108: z-band imaging from Gemini-North
  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. GRB 060108: ISAS early observations and near IR upper limit
  12. GRB060108: P200 Ks Observations
  13. GRB 060108: early UKIRT K-band observations
  14. Swift UVOT correction to GCN 4455
  15. GRB 060109: Swift Detection of a long burst
  16. GRB 060108: a dark burst?
  17. GRB 060108: Refined XRT analysis
  18. GRB 060108: VLT J-band observations
  19. GRB 060108: Mitsume optical observations
  20. GRB 060108: Swift/UVOT upper limits
  21. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  22. GRB060108: Faulkes Telescope observation
  23. GRB 060108: Refined analysis of the Swift-BAT burst
  24. GRB 060108: Swift XRT position
  25. GRB060108: Swift detection of its 100th GRB
  26. GRB 060105: Radio observations
  27. GRB 060105: MDM Observation
  28. Konus-Wind observation of GRB 060105
  29. GRB 060105: ISAS observations and near IR upper limit
  30. GRB 060105: Swift/UVOT upper limits
  31. GRB 060105: Mitsume optical observations
  32. GRB 060105: BAT refined analysis
  33. GRB 060102 - no XRT afterglow
  34. GRB 060105: XRT refined analysis
  35. GRB060105: Swift detection of a bright long burst
  36. Swift-BAT trigger 175653 is not an astrophysical source
  37. Swift-BAT trigger 175653 is probably not a GRB
  38. GRB 060102: Swift-BAT refined analysis
  39. Time Correction to GRB 060102
  40. GRB 060102: Swift-BAT detection of a burst
  41. GRB051211B: optical observations
  42. GRB051227: SARA Observations
  43. GRB 051221B: Optical Observations with Kuiper 1.54m
  44. GRB051221B: Radio observations
  45. GRB051227: Radio Observations
  46. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  47. GRB 051227: Gemini observations
  48. GRB 051227: Keck Spectroscopy
  49. GRB 051227: Magellan r'-band Imaging/Astrometry
  50. GRB 051227: refined analysis of VLT images
  51. GRB 051227: P60 Observations
  52. GRB 051227: MDM Observation
  53. GRB 051227: R-band object in the XRT error circle
  54. GRB 051227: Joint Swift-HETE Spectral Analysis
  55. GRB 051227: XRT refined analysis
  56. GRB 051227: Further analysis of the Swift-BAT burst
  57. GRB 051227: Refined analysis of the Swift-BAT burst
  58. GRB051227: SDSS pre-burst observations
  59. GRB 051227: Swift detection of a burst
  60. Konus-Wind observation of GRB 051221A
  61. GRB051221A: Suzaku WAM observation of the prompt emission
  62. GRB051016: analysis of the XMM-Newton observation
  63. GRB 051221A: Detection at 251nm with Swift UVOT
  64. GRB 051221A: Chandra Afterglow Position
  65. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  66. GRB 051221B: ROTSE-III Optical Limits
  67. GRB 051221B: TAROT optical limits
  68. GRB 051221A: WSRT Radio Observations
  69. GRB 051221B: Refined analysis of the Swift-BAT burst
  70. Possible GRB 051221B: MDM Optical Detection
  71. GRB 051221A: RAPTOR Fading Counterpart Constraint
  72. GRB 051221B: BOOTES optical observations.
  73. Possible GRB 051221B: Swift XRT position
  74. Swift-BAT detection of a possible burst
  75. GRB 051221: Discovery of fading optical afterglow
  76. GRB 051221: Swift XRT refined analysis
  77. GRB 051221: Swift/UVOT upper limits
  78. GRB 051221: No variability in Gemini data
  79. GRB 051221: Gemini observations
  80. GRB 051221: Improved astrometry of the IR counterpart
  81. GRB051221: K-band source
  82. GRB 051221: XRT position
  83. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  84. GRB 051221: Swift detection of a bright short burst
  85. Refined analysis of the SWIFT J1626.6-5156
  86. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  87. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  88. GRB 051211B: optical afterglow
  89. Swift detection of an RS CVn flare star
  90. Swift Trigger 172767 is not a GRB
  91. GRB 051215: Swift detection of a possible burst
  92. GRB 051215: A short GRB in a cluster?
  93. GRB051211B: Probable radio afterglow
  94. GRB051105: optical observations
  95. GRB 051213: Swift-BAT refined analysis
  96. GRB051211B: XRT refined analysis
  97. GRB 051213: Swift-BAT detection of a burst
  98. GRB 051211A: Swift/UVOT upper limits
  99. GRB 051211B: Swift/UVOT upper limits - correction
  100. GRB 051211B: Swift/UVOT upper limits

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