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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"

18568 results found.

  1. GRB 060123: Swift refined analysis of an unusual GRB
  2. GRB060124, BVRcIc field calibration
  3. GRB060105: refined analysis of the Suzaku observation
  4. GRB 060124: HETE detection and spectrum of the main peak
  5. Konus-Wind observation of GRB 060124
  6. GRB060124: detailed XRT analysis
  7. GRB 060124 Optical Observations
  8. GRB 060124: R band Observations
  9. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  10. GRB 060123: Swift detection of a very long, faint burst
  11. GRB 060124: TAROT optical limits
  12. GRB 060124: Swift/UVOT Observation
  13. GRB 060124: Confirmation of the Afterglow
  14. GRB 060124: XRT position
  15. GRB 060124: Optical Observations at Tautenburg
  16. GRB 060117: Suzaku WAM observation of the prompt emission
  17. GRB060124:MASTER optical observation
  18. GRB 060111B: Suzaku WAM observation of the prompt emission
  19. GRB 060124: Swift-BAT detection of a burst
  20. GRB 060116: Radio Detection
  21. GRB 060116: MARGE optical observations
  22. GRB 060121: Swift/UVOT upper limits
  23. GRB 060121: Liverpool Telescopes optical limits
  24. GRB 060121: Swift XRT refined analysis
  25. GRB 060121: Swift XRT refined position
  26. GRB 060117: pseudo-z from spectral parameters of the prompt emission
  27. Konus-Wind observation of GRB 060117
  28. GRB 060117: Refined analysis of the Swift-BAT burst
  29. GRB 060117: FRAM optical afterglow candidate
  30. GRB 060117: Swift-BAT detection of a bright burst
  31. GRB 060116: Refined analysis of the Swift-BAT burst
  32. GRB 060116: Swift/UVOT upper limits
  33. GRB060115: REM observations
  34. GRB 060110: XRT position and analysis
  35. GRB 060116: ROTSE-III Optical Limits
  36. GRB060116: XRT position
  37. GRB060116: Faulkes North observation
  38. GRB 060116: Swift-BAT detection of a burst
  39. GRB 060115: Refined analysis of the Swift-BAT burst
  40. GRB 060115: Swift/UVOT upper limits
  41. GRB 060115: Swift XRT refined analysis
  42. GRB 060114: Swift/UVOT Observations
  43. GRB 060115: MITSuME optical afterglow candidate
  44. GRB 060115: Swift detection of a burst
  45. GRB 060114: Swift XRT upper limit
  46. GRB 060110: KAIT observations
  47. GRB 060111B: Swift XRT refined analysis
  48. GRB 060111A: refined UVOT anaysis
  49. GRB 060111B: TAROT optical observation
  50. GRB060111A: RTT150 optical observations
  51. GRB060111B: RTT150, possible host galaxy
  52. GRB 060111B: Refined analysis of the Swift-BAT burst
  53. GRB 060110: MARGE observations
  54. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  55. GRB 060111B: Swift detection of a burst
  56. GRB 060111: Swift-BAT Refined Analysis
  57. GRB 060111: TAROT optical observation
  58. GRB 060111: possible UVOT counterpart
  59. GRB060111 : XRT refined analysis
  60. GRB 060111: ROTSE-III Optical Limits
  61. GRB 060111: Swift detection of a burst
  62. GRB 060110: Swift-BAT refined analysis
  63. GRB 060109: Swift-BAT refined analysis
  64. GRB 060110a: RAPTOR detection of early optical emission.
  65. Correction to GRB 060109 XRT analysis
  66. GRB 060110: Swift-BAT detection of a burst
  67. GRB 060109: Refined Swift-XRT analysis
  68. GRB 060109: Swift/UVOT upper limits
  69. Swift UVOT correction to GCN 4455
  70. GRB 060109: Swift Detection of a long burst
  71. GRB 060108: Refined XRT analysis
  72. GRB 060108: VLT J-band observations
  73. GRB 060108: Swift/UVOT upper limits
  74. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  75. GRB060108: Faulkes Telescope observation
  76. GRB 060108: Refined analysis of the Swift-BAT burst
  77. GRB 060108: Swift XRT position
  78. GRB060108: Swift detection of its 100th GRB
  79. GRB 060105: Radio observations
  80. Konus-Wind observation of GRB 060105
  81. GRB 060105: Swift/UVOT upper limits
  82. GRB 060105: BAT refined analysis
  83. GRB 060105: XRT refined analysis
  84. GRB060105: Swift detection of a bright long burst
  85. Swift-BAT trigger 175653 is not an astrophysical source
  86. Swift-BAT trigger 175653 is probably not a GRB
  87. GRB 060102: Swift-BAT refined analysis
  88. Time Correction to GRB 060102
  89. GRB 060102: Swift-BAT detection of a burst
  90. GRB051211B: optical observations
  91. GRB051227: SARA Observations
  92. GRB 051221B: Optical Observations with Kuiper 1.54m
  93. GRB051221B: Radio observations
  94. GRB051227: Radio Observations
  95. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  96. GRB 051227: MDM Observation
  97. GRB 051227: Joint Swift-HETE Spectral Analysis
  98. GRB 051227: XRT refined analysis
  99. GRB 051227: Further analysis of the Swift-BAT burst
  100. GRB 051227: Refined analysis of the Swift-BAT burst

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