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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"

19010 results found.

  1. Swift-BAT trigger 180151 is unknown origin at this time
  2. GRB 060202: Refined analysis of the Swift-BAT burst
  3. GRB060202, optical observation
  4. GRB 060202: Swift/UVOT upper limits
  5. GRB 060202: Swift XRT Team Refined Analysis
  6. GRB060202: Faulkes North observation
  7. GRB 060202: Swift detection of a burst
  8. GRB 060130: Swift/XRT observation
  9. GRB 060123: VLA Radio Observations
  10. Possible GRB 051221B: MDM Correction
  11. GRB 060123: Swift refined analysis of an unusual GRB
  12. GRB060124, BVRcIc field calibration
  13. GRB060105: refined analysis of the Suzaku observation
  14. GRB 060124: HETE detection and spectrum of the main peak
  15. Konus-Wind observation of GRB 060124
  16. GRB060124: detailed XRT analysis
  17. GRB 060124 Optical Observations
  18. GRB 060124: R band Observations
  19. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  20. GRB 060123: Swift detection of a very long, faint burst
  21. GRB 060124: TAROT optical limits
  22. GRB 060124: Swift/UVOT Observation
  23. GRB 060124: Confirmation of the Afterglow
  24. GRB 060124: XRT position
  25. GRB 060124: Optical Observations at Tautenburg
  26. GRB 060117: Suzaku WAM observation of the prompt emission
  27. GRB060124:MASTER optical observation
  28. GRB 060111B: Suzaku WAM observation of the prompt emission
  29. GRB 060124: Swift-BAT detection of a burst
  30. GRB 060116: Radio Detection
  31. GRB 060116: MARGE optical observations
  32. GRB 060121: Swift/UVOT upper limits
  33. GRB 060121: Liverpool Telescopes optical limits
  34. GRB 060121: Swift XRT refined analysis
  35. GRB 060121: Swift XRT refined position
  36. GRB 060117: pseudo-z from spectral parameters of the prompt emission
  37. Konus-Wind observation of GRB 060117
  38. GRB 060117: Refined analysis of the Swift-BAT burst
  39. GRB 060117: FRAM optical afterglow candidate
  40. GRB 060117: Swift-BAT detection of a bright burst
  41. GRB 060116: Refined analysis of the Swift-BAT burst
  42. GRB 060116: Swift/UVOT upper limits
  43. GRB060115: REM observations
  44. GRB 060110: XRT position and analysis
  45. GRB 060116: ROTSE-III Optical Limits
  46. GRB060116: XRT position
  47. GRB060116: Faulkes North observation
  48. GRB 060116: Swift-BAT detection of a burst
  49. GRB 060115: Refined analysis of the Swift-BAT burst
  50. GRB 060115: Swift/UVOT upper limits
  51. GRB 060115: Swift XRT refined analysis
  52. GRB 060114: Swift/UVOT Observations
  53. GRB 060115: MITSuME optical afterglow candidate
  54. GRB 060115: Swift detection of a burst
  55. GRB 060114: Swift XRT upper limit
  56. GRB 060110: KAIT observations
  57. GRB 060111B: Swift XRT refined analysis
  58. GRB 060111A: refined UVOT anaysis
  59. GRB 060111B: TAROT optical observation
  60. GRB060111A: RTT150 optical observations
  61. GRB060111B: RTT150, possible host galaxy
  62. GRB 060111B: Refined analysis of the Swift-BAT burst
  63. GRB 060110: MARGE observations
  64. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  65. GRB 060111B: Swift detection of a burst
  66. GRB 060111: Swift-BAT Refined Analysis
  67. GRB 060111: TAROT optical observation
  68. GRB 060111: possible UVOT counterpart
  69. GRB060111 : XRT refined analysis
  70. GRB 060111: ROTSE-III Optical Limits
  71. GRB 060111: Swift detection of a burst
  72. GRB 060110: Swift-BAT refined analysis
  73. GRB 060109: Swift-BAT refined analysis
  74. GRB 060110a: RAPTOR detection of early optical emission.
  75. Correction to GRB 060109 XRT analysis
  76. GRB 060110: Swift-BAT detection of a burst
  77. GRB 060109: Refined Swift-XRT analysis
  78. GRB 060109: Swift/UVOT upper limits
  79. Swift UVOT correction to GCN 4455
  80. GRB 060109: Swift Detection of a long burst
  81. GRB 060108: Refined XRT analysis
  82. GRB 060108: VLT J-band observations
  83. GRB 060108: Swift/UVOT upper limits
  84. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  85. GRB060108: Faulkes Telescope observation
  86. GRB 060108: Refined analysis of the Swift-BAT burst
  87. GRB 060108: Swift XRT position
  88. GRB060108: Swift detection of its 100th GRB
  89. GRB 060105: Radio observations
  90. Konus-Wind observation of GRB 060105
  91. GRB 060105: Swift/UVOT upper limits
  92. GRB 060105: BAT refined analysis
  93. GRB 060105: XRT refined analysis
  94. GRB060105: Swift detection of a bright long burst
  95. Swift-BAT trigger 175653 is not an astrophysical source
  96. Swift-BAT trigger 175653 is probably not a GRB
  97. GRB 060102: Swift-BAT refined analysis
  98. Time Correction to GRB 060102
  99. GRB 060102: Swift-BAT detection of a burst
  100. GRB051211B: optical observations

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