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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"

35427 results found.

  1. GRB 081204: Swift XRT afterglow candidate
  2. GRB081203A: optical observation
  3. GRB 081204 : a long GRB localized by INTEGRAL
  4. VLA Radio upper limit on GRB 081203A
  5. Swift-XRT observations of GRB 081203B
  6. Konus-Wind observation of GRB 081203A
  7. Konus-Wind observation of GRB 081203B
  8. GRB081203A: Swift-XRT refined analysis
  9. GRB 081203B: optical observations
  10. GRB 081203B: SDSS upper limits at the position of the optical afterglow
  11. Swift/UVOT detection of GRB081203B
  12. GRB 081203B: Swift-XRT candidate afterglow.
  13. GRB 081203A: optical observations
  14. Swift UVOT observations of GRB 081203A
  15. GRB 081203B: Naming correction for burst detected in Swift-BAT slew data
  16. GRB081203A: Swift/UVOT grism redshift
  17. GRB 081203A: Burst detection from Swift-BAT slew data
  18. GRB 081203A: Swift-BAT refined analysis
  19. GRB 081203: Enhanced Swift-XRT position
  20. GRB 081130B: MASTER prompt optical observations
  21. GRB081203: optical observation
  22. GRB 081203: Swift detection of a burst with a bright optical counterpart
  23. GRB 081128: optical observation
  24. GRB 081130B: Fermi GBM detection
  25. GRB 081130: Fermi GBM detection
  26. GRB 081126: afterglow photometry
  27. GRB 081126: Fermi GBM detection
  28. Fermi Gamma-ray Burst Monitor trigger 249166723 reclassification
  29. VLA Radio upper limit on GRB 081126
  30. GRB 081129: Fermi GBM detection
  31. GRB 081130: MASTER VWF prompt optical observations Fermi GRB
  32. GRB 081128A: optical observations
  33. Trigger 335971: Swift possible detection of a burst
  34. GRB081128: Swift/UVOT Upper Limits
  35. GRB 081122B: Fermi GBM Detection
  36. GRB 081128: Swift-XRT refined analysis
  37. GRB 081128: Liverpool Telescope afterglow confirmation
  38. GRB081128: optical observations
  39. GRB 081128: Swift-BAT refined analysis
  40. GRB 081128: Enhanced Swift-XRT position
  41. GRB 081128: Optical observation of xinglong TNT
  42. GRB 081128: Swift detection of a burst
  43. GRB 081126: Swift observations continuing
  44. GRB081126: Afterglow photometry from Crni Vrh
  45. GRB 081126: GRT Optical Observation
  46. GRB 081127: Swift/UVOT Upper Limits
  47. GRB 081127: Swift-XRT refined analysis
  48. GRB 081127: Enhanced Swift-XRT position
  49. GRB 081126: Confirmation of the Optical Afterglow
  50. GRB 081127: Swift-BAT refined analysis
  51. Konus-Wind observation of GRB 081126
  52. GRB 081126: Swift-XRT refined analysis
  53. GRB 081127: Swift detection of a burst
  54. GRB 081126: Swift/UVOT Observations
  55. GRB 081126: optical observations
  56. GRB 081126: Swift-BAT refined analysis
  57. GRB 081126: Enhanced Swift-XRT position
  58. GRB 081126: TAROT Calern observatory optical observations
  59. GRB 081126: Swift detection of a burst
  60. GRB 081125: Fermi GBM detection
  61. GRB 081124: Fermi GBM detection
  62. GRB 081120: Fermi GBM detection
  63. GRB 081118: Fermi GBM detection.
  64. GRB 081122: Fermi GBM detection
  65. Konus-Wind observation of GRB 081121
  66. GRB 081121, SMARTS optical/IR afterglow observations
  67. GRB081121: Fermi GBM detection
  68. Fermi GBM detection of a weak source
  69. GRB081121: Refined Swift/UVOT observations
  70. GRB 081121: Swift-XRT refined analysis
  71. GRB 081121: Magellan Redshift
  72. GRB 081121: Enhanced Swift-XRT position
  73. GRB 081121: GROND observations
  74. GRB 081121: Swift-BAT refined analysis
  75. GRB 081121: Swift detection of a burst
  76. GRB 081121: ROTSE-III Detection of Optical Counterpart
  77. GRB 081016b, SMARTS optical/IR observations
  78. GRB 081119: Fermi GBM detection
  79. VLA Radio upper limit on GRB 081118
  80. GRB 081118: VLT redshift
  81. GRB 081118: Swift-XRT refined analysis
  82. GRB 081118: GROND detection of afterglow
  83. GRB 081118: optical afterglow candidate
  84. GRB 081118: Swift UVOT Upper Limits
  85. GRB 081118: Swift-BAT refined analysis
  86. GRB 081118: Enhanced Swift-XRT position
  87. GRB 081118: Swift detection of a burst
  88. GRB 081109A: confirmation of possible detection host galaxy
  89. Further Swift-XRT observations of the probable GRB 081105.
  90. GRB 081113: Fermi GBM detection
  91. GRB 081102: RTT150 Optical observations
  92. GRB 081110: Fermi GBM detection
  93. GRB 081110: MASTER: first optical observations Fermi GRB
  94. GRB 081109: TAROT La Silla observatory optical observations
  95. GRB 081102: MASTER refind and final results
  96. GRB 081109: GROND redshift limit and host extinction
  97. GRB 081025: Swift-XRT further analysis
  98. GRB 081024B: Swift-XRT late-time observations
  99. Swift-BAT refined analysis of trigger 334129
  100. GRB 081109B: Swift/UVOT refined analysis

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