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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"

27404 results found.

  1. GRB 081221: Swift detection of a burst
  2. GRB 081217: Fermi GBM detection
  3. GRB 081211B: Further Swift-XRT analysis
  4. GRB 081215B: Fermi GBM detection
  5. GRB 081216: Suzaku WAM observation of the prompt emission
  6. GRB 081216 : Fermi GBM observation
  7. GRB 081215A: Fermi GBM detection
  8. GRB 081118: Zadko observations
  9. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  10. GRB 0811215A: MASTER prompt optical observations
  11. GRB 081215A: Andromeda inside Fermi error box: MASTER observations
  12. GRB 0811215A: Andromeda inside Fermi error box: MASTER observations
  13. Possible GRB 081211B: Swift/UVOT Upper Limits
  14. GRB 081213: Fermi GBM detection
  15. Possible GRB 081211B - Swift-XRT analysis
  16. GRB 081207: Fermi GBM detection
  17. GRB 081209: Fermi GBM detection
  18. GRB 081211B(?): Possible burst detection from Swift-BAT slew data
  19. GRB 081210, SMARTS optical/IR observations
  20. GRB 081211: Swift-BAT refined analysis
  21. GRB 081211: Swift XRT refined analysis
  22. GRB 081211: Enhanced Swift-XRT position
  23. GRB 081211: Swift detection of a burst
  24. GRB 081210: Swift-XRT refined analysis
  25. GRB081203B: optical observations
  26. GRB 081210: Enhanced Swift-XRT position
  27. GRB 081210: Swift-BAT refined analysis
  28. GRB 081210: Swift detection of a burst with optical afterglow
  29. IPN triangulation of short hard GRB 081209
  30. GRB 081203A: optical observations
  31. GRB 081206C: Fermi GBM detection
  32. Radio observation of GRB 081121 with ATCA
  33. Radio observation of GRB 081118 with ATCA
  34. GRB 081206B: Fermi GBM detection
  35. GRB 081206: Fermi GBM detection
  36. GRB 081128: afterglow observations
  37. GRB 081203B: Suzaku WAM observation of the prompt emission
  38. Radio observation of GRB 081109 with ATCA
  39. Radio observation of GRB 081104 with ATCA
  40. Radio observation of GRB 081029 with ATCA
  41. Radio observation of GRB 081008 with ATCA
  42. GRB081203A: Ashra-1 observation of early optical and VHE-neutrino emission
  43. GRB081203A: Optical observations at Ishigaki
  44. GRB 081204: GROND Observations
  45. Radio detection of GRB 081203B with the VLA
  46. GRB081203A: Radio upper limit at 15 GHz
  47. GRB 081204B: Fermi GBM detection
  48. GRB 081204: Swift/UVOT Upper Limits
  49. GRB 081204: Swift XRT afterglow confirmation
  50. GRB081203A: MITSuME optical observation
  51. GRB081203A: optical observation
  52. GRB 081204 : a long GRB localized by INTEGRAL
  53. VLA Radio upper limit on GRB 081203A
  54. Swift-XRT observations of GRB 081203B
  55. GRB081203A: Swift-XRT refined analysis
  56. GRB 081203B: optical observations
  57. Swift/UVOT detection of GRB081203B
  58. GRB 081203B: Swift-XRT candidate afterglow.
  59. GRB 081203A: optical observations
  60. GRB081203A: Swift/UVOT grism redshift
  61. GRB 081203A: Burst detection from Swift-BAT slew data
  62. GRB 081203A: Swift-BAT refined analysis
  63. GRB 081203: Enhanced Swift-XRT position
  64. GRB 081130B: MASTER prompt optical observations
  65. GRB081203: optical observation
  66. GRB 081203: Swift detection of a burst with a bright optical counterpart
  67. GRB 081130B: Fermi GBM detection
  68. GRB 081130: Fermi GBM detection
  69. Swift Trigger 335971: Swift/UVOT Observations
  70. GRB 081126: afterglow photometry
  71. GRB 081126: Fermi GBM detection
  72. VLA Radio upper limit on GRB 081126
  73. GRB 081129: Fermi GBM detection
  74. GRB 081130: MASTER VWF prompt optical observations Fermi GRB
  75. GRB 081128A: optical observations
  76. Trigger 335971: Swift possible detection of a burst
  77. GRB081128: Swift/UVOT Upper Limits
  78. GRB 081122B: Fermi GBM Detection
  79. GRB 081128: Swift-XRT refined analysis
  80. GRB 081128: Liverpool Telescope afterglow confirmation
  81. GRB081128: optical observations
  82. GRB 081128: Swift-BAT refined analysis
  83. GRB 081128: Enhanced Swift-XRT position
  84. GRB 081128: Optical observation of xinglong TNT
  85. GRB 081128: Swift detection of a burst
  86. GRB081126: Afterglow photometry from Crni Vrh
  87. GRB 081126: GRT Optical Observation
  88. GRB 081127: Swift/UVOT Upper Limits
  89. GRB 081127: Swift-XRT refined analysis
  90. GRB 081127: Enhanced Swift-XRT position
  91. GRB 081127: Swift-BAT refined analysis
  92. GRB 081126: Swift-XRT refined analysis
  93. GRB 081127: Swift detection of a burst
  94. GRB 081126: Swift/UVOT Observations
  95. GRB 081126: optical observations
  96. GRB 081126: Swift-BAT refined analysis
  97. GRB 081126: Enhanced Swift-XRT position
  98. GRB 081126: TAROT Calern observatory optical observations
  99. GRB 081126: Swift detection of a burst
  100. GRB 081125: Fermi GBM detection

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