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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"

18640 results found.

  1. GRB 060117: FRAM optical afterglow candidate
  2. GRB 060117: Swift-BAT detection of a bright burst
  3. GRB 060116: Refined analysis of the Swift-BAT burst
  4. GRB 060116: Swift/UVOT upper limits
  5. GRB060115: REM observations
  6. GRB 060110: XRT position and analysis
  7. GRB 060116: ROTSE-III Optical Limits
  8. GRB060116: XRT position
  9. GRB060116: Faulkes North observation
  10. GRB 060116: Swift-BAT detection of a burst
  11. GRB 060115: Refined analysis of the Swift-BAT burst
  12. GRB 060115: Swift/UVOT upper limits
  13. GRB 060115: Swift XRT refined analysis
  14. GRB 060114: Swift/UVOT Observations
  15. GRB 060115: MITSuME optical afterglow candidate
  16. GRB 060115: Swift detection of a burst
  17. GRB 060114: Swift XRT upper limit
  18. GRB 060110: KAIT observations
  19. GRB 060111B: Swift XRT refined analysis
  20. GRB 060111A: refined UVOT anaysis
  21. GRB 060111B: TAROT optical observation
  22. GRB060111A: RTT150 optical observations
  23. GRB060111B: RTT150, possible host galaxy
  24. GRB 060111B: Refined analysis of the Swift-BAT burst
  25. GRB 060110: MARGE observations
  26. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  27. GRB 060111B: Swift detection of a burst
  28. GRB 060111: Swift-BAT Refined Analysis
  29. GRB 060111: TAROT optical observation
  30. GRB 060111: possible UVOT counterpart
  31. GRB060111 : XRT refined analysis
  32. GRB 060111: ROTSE-III Optical Limits
  33. GRB 060111: Swift detection of a burst
  34. GRB 060110: Swift-BAT refined analysis
  35. GRB 060109: Swift-BAT refined analysis
  36. GRB 060110a: RAPTOR detection of early optical emission.
  37. Correction to GRB 060109 XRT analysis
  38. GRB 060110: Swift-BAT detection of a burst
  39. GRB 060109: Refined Swift-XRT analysis
  40. GRB 060109: Swift/UVOT upper limits
  41. Swift UVOT correction to GCN 4455
  42. GRB 060109: Swift Detection of a long burst
  43. GRB 060108: Refined XRT analysis
  44. GRB 060108: VLT J-band observations
  45. GRB 060108: Swift/UVOT upper limits
  46. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  47. GRB060108: Faulkes Telescope observation
  48. GRB 060108: Refined analysis of the Swift-BAT burst
  49. GRB 060108: Swift XRT position
  50. GRB060108: Swift detection of its 100th GRB
  51. GRB 060105: Radio observations
  52. Konus-Wind observation of GRB 060105
  53. GRB 060105: Swift/UVOT upper limits
  54. GRB 060105: BAT refined analysis
  55. GRB 060105: XRT refined analysis
  56. GRB060105: Swift detection of a bright long burst
  57. Swift-BAT trigger 175653 is not an astrophysical source
  58. Swift-BAT trigger 175653 is probably not a GRB
  59. GRB 060102: Swift-BAT refined analysis
  60. Time Correction to GRB 060102
  61. GRB 060102: Swift-BAT detection of a burst
  62. GRB051211B: optical observations
  63. GRB051227: SARA Observations
  64. GRB 051221B: Optical Observations with Kuiper 1.54m
  65. GRB051221B: Radio observations
  66. GRB051227: Radio Observations
  67. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  68. GRB 051227: MDM Observation
  69. GRB 051227: Joint Swift-HETE Spectral Analysis
  70. GRB 051227: XRT refined analysis
  71. GRB 051227: Further analysis of the Swift-BAT burst
  72. GRB 051227: Refined analysis of the Swift-BAT burst
  73. GRB051227: SDSS pre-burst observations
  74. GRB 051227: Swift detection of a burst
  75. Konus-Wind observation of GRB 051221A
  76. GRB051221A: Suzaku WAM observation of the prompt emission
  77. GRB051016: analysis of the XMM-Newton observation
  78. GRB 051221A: Detection at 251nm with Swift UVOT
  79. GRB 051221A: Chandra Afterglow Position
  80. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  81. GRB 051221B: ROTSE-III Optical Limits
  82. GRB 051221B: TAROT optical limits
  83. GRB 051221A: WSRT Radio Observations
  84. GRB 051221B: Refined analysis of the Swift-BAT burst
  85. Possible GRB 051221B: MDM Optical Detection
  86. GRB 051221A: RAPTOR Fading Counterpart Constraint
  87. GRB 051221B: BOOTES optical observations.
  88. Possible GRB 051221B: Swift XRT position
  89. Swift-BAT detection of a possible burst
  90. GRB 051221: Swift XRT refined analysis
  91. GRB 051221: Swift/UVOT upper limits
  92. GRB 051221: XRT position
  93. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  94. GRB 051221: Swift detection of a bright short burst
  95. Refined analysis of the SWIFT J1626.6-5156
  96. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  97. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  98. GRB 051211B: optical afterglow
  99. Swift detection of an RS CVn flare star
  100. Swift Trigger 172767 is not a GRB

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