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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"

27396 results found.

  1. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  2. GRB 0811215A: MASTER prompt optical observations
  3. GRB 081215A: Andromeda inside Fermi error box: MASTER observations
  4. GRB 0811215A: Andromeda inside Fermi error box: MASTER observations
  5. Possible GRB 081211B: Swift/UVOT Upper Limits
  6. GRB 081213: Fermi GBM detection
  7. Possible GRB 081211B - Swift-XRT analysis
  8. GRB 081207: Fermi GBM detection
  9. GRB 081209: Fermi GBM detection
  10. GRB 081211B(?): Possible burst detection from Swift-BAT slew data
  11. GRB 081210, SMARTS optical/IR observations
  12. GRB 081211: Swift-BAT refined analysis
  13. GRB 081211: Swift XRT refined analysis
  14. GRB 081211: Enhanced Swift-XRT position
  15. GRB 081211: Swift detection of a burst
  16. GRB 081210: Swift-XRT refined analysis
  17. GRB081203B: optical observations
  18. GRB 081210: Enhanced Swift-XRT position
  19. GRB 081210: Swift-BAT refined analysis
  20. GRB 081210: Swift detection of a burst with optical afterglow
  21. IPN triangulation of short hard GRB 081209
  22. GRB 081203A: optical observations
  23. GRB 081206C: Fermi GBM detection
  24. Radio observation of GRB 081121 with ATCA
  25. Radio observation of GRB 081118 with ATCA
  26. GRB 081206B: Fermi GBM detection
  27. GRB 081206: Fermi GBM detection
  28. GRB 081128: afterglow observations
  29. GRB 081203B: Suzaku WAM observation of the prompt emission
  30. Radio observation of GRB 081109 with ATCA
  31. Radio observation of GRB 081104 with ATCA
  32. Radio observation of GRB 081029 with ATCA
  33. Radio observation of GRB 081008 with ATCA
  34. GRB081203A: Ashra-1 observation of early optical and VHE-neutrino emission
  35. GRB081203A: Optical observations at Ishigaki
  36. GRB 081204: GROND Observations
  37. Radio detection of GRB 081203B with the VLA
  38. GRB081203A: Radio upper limit at 15 GHz
  39. GRB 081204B: Fermi GBM detection
  40. GRB 081204: Swift/UVOT Upper Limits
  41. GRB 081204: Swift XRT afterglow confirmation
  42. GRB081203A: MITSuME optical observation
  43. GRB081203A: optical observation
  44. GRB 081204 : a long GRB localized by INTEGRAL
  45. VLA Radio upper limit on GRB 081203A
  46. Swift-XRT observations of GRB 081203B
  47. GRB081203A: Swift-XRT refined analysis
  48. GRB 081203B: optical observations
  49. Swift/UVOT detection of GRB081203B
  50. GRB 081203B: Swift-XRT candidate afterglow.
  51. GRB 081203A: optical observations
  52. GRB081203A: Swift/UVOT grism redshift
  53. GRB 081203A: Burst detection from Swift-BAT slew data
  54. GRB 081203A: Swift-BAT refined analysis
  55. GRB 081203: Enhanced Swift-XRT position
  56. GRB 081130B: MASTER prompt optical observations
  57. GRB081203: optical observation
  58. GRB 081203: Swift detection of a burst with a bright optical counterpart
  59. GRB 081130B: Fermi GBM detection
  60. GRB 081130: Fermi GBM detection
  61. Swift Trigger 335971: Swift/UVOT Observations
  62. GRB 081126: afterglow photometry
  63. GRB 081126: Fermi GBM detection
  64. VLA Radio upper limit on GRB 081126
  65. GRB 081129: Fermi GBM detection
  66. GRB 081130: MASTER VWF prompt optical observations Fermi GRB
  67. GRB 081128A: optical observations
  68. Trigger 335971: Swift possible detection of a burst
  69. GRB081128: Swift/UVOT Upper Limits
  70. GRB 081122B: Fermi GBM Detection
  71. GRB 081128: Swift-XRT refined analysis
  72. GRB 081128: Liverpool Telescope afterglow confirmation
  73. GRB081128: optical observations
  74. GRB 081128: Swift-BAT refined analysis
  75. GRB 081128: Enhanced Swift-XRT position
  76. GRB 081128: Optical observation of xinglong TNT
  77. GRB 081128: Swift detection of a burst
  78. GRB081126: Afterglow photometry from Crni Vrh
  79. GRB 081126: GRT Optical Observation
  80. GRB 081127: Swift/UVOT Upper Limits
  81. GRB 081127: Swift-XRT refined analysis
  82. GRB 081127: Enhanced Swift-XRT position
  83. GRB 081127: Swift-BAT refined analysis
  84. GRB 081126: Swift-XRT refined analysis
  85. GRB 081127: Swift detection of a burst
  86. GRB 081126: Swift/UVOT Observations
  87. GRB 081126: optical observations
  88. GRB 081126: Swift-BAT refined analysis
  89. GRB 081126: Enhanced Swift-XRT position
  90. GRB 081126: TAROT Calern observatory optical observations
  91. GRB 081126: Swift detection of a burst
  92. GRB 081125: Fermi GBM detection
  93. GRB 081124: Fermi GBM detection
  94. GRB 081120: Fermi GBM detection
  95. GRB 081118: Fermi GBM detection.
  96. GRB 081122: Fermi GBM detection
  97. GRB 081121, SMARTS optical/IR afterglow observations
  98. Fermi GBM detection of a weak source
  99. GRB081121: Refined Swift/UVOT observations
  100. GRB 081121: Swift-XRT refined analysis

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