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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. GRB081203A: MITSuME optical observation
  2. GRB 081203A: Optical observations of Xinglong TNT telescope
  3. GRB 081203A: Skynet/GORT Detections
  4. GRB 081204: Swift XRT afterglow candidate
  5. GRB081203A: optical observation
  6. GRB 081204 : a long GRB localized by INTEGRAL
  7. VLA Radio upper limit on GRB 081203A
  8. Swift-XRT observations of GRB 081203B
  9. Konus-Wind observation of GRB 081203A
  10. Konus-Wind observation of GRB 081203B
  11. GRB081203A: Swift-XRT refined analysis
  12. GRB 081203B: optical observations
  13. GRB 081203B: SDSS upper limits at the position of the optical afterglow
  14. Swift/UVOT detection of GRB081203B
  15. GRB 081203B: Swift-XRT candidate afterglow.
  16. GRB 081203A: optical observations
  17. Swift UVOT observations of GRB 081203A
  18. GRB 081203B: Naming correction for burst detected in Swift-BAT slew data
  19. GRB081203A: Swift/UVOT grism redshift
  20. GRB 081203A: Burst detection from Swift-BAT slew data
  21. GRB 081203A: Swift-BAT refined analysis
  22. GRB 081203: Enhanced Swift-XRT position
  23. GRB 081130B: MASTER prompt optical observations
  24. GRB081203: optical observation
  25. GRB 081203: Swift detection of a burst with a bright optical counterpart
  26. GRB 081128: optical observation
  27. GRB 081130B: Fermi GBM detection
  28. GRB 081130: Fermi GBM detection
  29. Swift Trigger 335971: Swift/UVOT Observations
  30. GRB 081126: afterglow photometry
  31. GRB 081126: Fermi GBM detection
  32. Fermi Gamma-ray Burst Monitor trigger 249166723 reclassification
  33. VLA Radio upper limit on GRB 081126
  34. GRB 081129: Fermi GBM detection
  35. GRB 081130: MASTER VWF prompt optical observations Fermi GRB
  36. GRB 081128A: optical observations
  37. Swift Trigger 335971 is probably not a real source
  38. Trigger 335971: Swift possible detection of a burst
  39. GRB081128: Swift/UVOT Upper Limits
  40. SGR 1806-20: Fermi GBM detection.
  41. GRB 081122B: Fermi GBM Detection
  42. GRB 081128: Swift-XRT refined analysis
  43. GRB 081128: Liverpool Telescope afterglow confirmation
  44. GRB081128: optical observations
  45. GRB081128 : Lulin optical follow-ups
  46. GRB 081128: Swift-BAT refined analysis
  47. GRB 081128: Enhanced Swift-XRT position
  48. GRB 081128: Optical observation of xinglong TNT
  49. GRB 081128: Swift detection of a burst
  50. GRB 081126: Swift observations continuing
  51. GRB081126: Afterglow photometry from Crni Vrh
  52. GRB 081126: GRT Optical Observation
  53. GRB 081127: Swift/UVOT Upper Limits
  54. GRB 081127: Swift-XRT refined analysis
  55. GRB 081127: Enhanced Swift-XRT position
  56. GRB 081126: Confirmation of the Optical Afterglow
  57. GRB 081127: Swift-BAT refined analysis
  58. Konus-Wind observation of GRB 081126
  59. GRB 081126: Swift-XRT refined analysis
  60. GRB 081127: Swift detection of a burst
  61. GRB 081126: Swift/UVOT Observations
  62. GRB 081126: optical observations
  63. GRB 081126: Swift-BAT refined analysis
  64. GRB 081126: Enhanced Swift-XRT position
  65. GRB 081126: TAROT Calern observatory optical observations
  66. GRB 081126: Swift detection of a burst
  67. GRB 081125: Fermi GBM detection
  68. GRB 081124: Fermi GBM detection
  69. GRB 081120: Fermi GBM detection
  70. GRB 081118: Fermi GBM detection.
  71. GRB 081122: Fermi GBM detection
  72. Konus-Wind observation of GRB 081121
  73. GRB 081121, SMARTS optical/IR afterglow observations
  74. GRB081121: Fermi GBM detection
  75. Fermi GBM detection of a weak source
  76. GRB081121: Refined Swift/UVOT observations
  77. GRB 081121: Swift-XRT refined analysis
  78. GRB 081121: Magellan Redshift
  79. GRB 081121: Enhanced Swift-XRT position
  80. GRB 081121: GROND observations
  81. GRB 081121: Swift-BAT refined analysis
  82. GRB081121: Swift/UVOT observations
  83. GRB 081121: Swift detection of a burst
  84. GRB 081121: ROTSE-III Detection of Optical Counterpart
  85. GRB081118 : optical upper limit
  86. GRB 081016b, SMARTS optical/IR observations
  87. GRB 081119: Fermi GBM detection
  88. VLA Radio upper limit on GRB 081118
  89. GRB 081118: VLT redshift
  90. GRB 081118: Swift-XRT refined analysis
  91. GRB 081118: GROND detection of afterglow
  92. GRB 081118: optical afterglow candidate
  93. GRB 081118: Swift UVOT Upper Limits
  94. GRB 081118: Swift-BAT refined analysis
  95. GRB 081118: Enhanced Swift-XRT position
  96. GRB 081118: Swift detection of a burst
  97. GRB 081109A: confirmation of possible detection host galaxy
  98. Further Swift-XRT observations of the probable GRB 081105.
  99. GRB 081113: Fermi GBM detection
  100. GRB 081102: RTT150 Optical observations

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