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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"

3401 results found.

  1. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  2. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  3. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  4. GRB 221008A: Swift-XRT observations
  5. GRB 221008A: Tiled Swift observations
  6. GRB 221008A: MAXI/GSC detection
  7. GRB 221006A: Swift-XRT observations
  8. GRB 221006A: Tiled Swift observations
  9. GRB 221006A: MAXI/GSC detection
  10. Fermi trigger No 686588176: Global MASTER-Net observations report
  11. GRB 220927A: Fermi GBM Final Localization
  12. Fermi GRB 220925A: Global MASTER-Net observations report
  13. Fermi trigger No 685748699: Global MASTER-Net observations report
  14. Fermi trigger No 685452089: Global MASTER-Net observations report
  15. IceCube-220907A: No significant detection in HAWC
  16. Fermi trigger No 684716840: Global MASTER-Net observations report
  17. Fermi GRB 220912A: Global MASTER-Net observations report
  18. IceCube Alert 220907.28: Global MASTER-Net observations report
  19. Fermi GRB 220905A: Global MASTER-Net observations report
  20. Fermi GRB 220902A: Global MASTER-Net observations report
  21. Fermi trigger No 683537972: Global MASTER-Net observations report
  22. Fermi trigger No 683202084: Global MASTER-Net observations report
  23. Fermi trigger No 683183601: Global MASTER-Net observations report
  24. GRB 220825A: Fermi GBM observation
  25. GRB 220825A: Swift/BAT-GUANO detection
  26. GRB 220825A: Fermi GBM Final Localization
  27. Fermi trigger No 682918137: Global MASTER-Net observations report
  28. Fermi trigger No 681719116: Global MASTER-Net observations report
  29. Fermi trigger No 681271717: Global MASTER-Net observations report
  30. Fermi trigger No 680782656: Global MASTER-Net observations report
  31. Fermi GRB 220728A: Global MASTER-Net observations report
  32. GRB 220715B: BOOTES-network optical upper limits
  33. Fermi trigger No 679248723: Global MASTER-Net observations report
  34. Fermi GRB 220711B: Global MASTER-Net observations report
  35. GRB 220706A: MAXI/GSC detection 84 minutes after the Swift Trigger
  36. MAXI GRB220706.73: Global MASTER-Net observations report
  37. GRB 200701A: KAIT Optical Upper Limit
  38. Trigger 1113743: Swift detection of MAXI J0655-013
  39. Fermi trigger No 678058621: Global MASTER-Net observations report
  40. IceCube Alert 220627.74: Global MASTER-Net observations report
  41. Fermi GRB 220623B: Global MASTER-Net observations report
  42. GRB 220624A: AGILE detection
  43. Swift Detection of MAXI J0655-013
  44. GRB 220618A: Swift-BAT refined analysis
  45. Fermi trigger No 677377371: Global MASTER-Net observations report
  46. Fermi trigger No 677307509: Global MASTER-Net observations report
  47. Fermi trigger No 677174940: Global MASTER-Net observations report
  48. IPN triangulation of GRB 220613A
  49. Fermi trigger No 676909037: Global MASTER-Net observations report
  50. Fermi GRB 220610A: Global MASTER-Net observations report
  51. MAXI GRB220607.31: Global MASTER-Net observations report
  52. MAXI GRB220607.41: Global MASTER-Net observations report
  53. Konus-Wind detection of GRB 220601A
  54. Fermi trigger No 675992935: Global MASTER-Net observations report
  55. Fermi trigger No 675411172: Global MASTER-Net observations report
  56. GRB 220521A: ISON-Castelgrande observatory optical observations
  57. Swift GRB220521.97: Global MASTER-Net observations report
  58. Konus-Wind detection of GRB 220506A
  59. Konus-Wind detection of GRB 220514B
  60. GRB 220514B: Swift-XRT observations
  61. GRB 220514B: Tiled Swift observations
  62. IceCube-220513A: No significant detection in HAWC
  63. GRB 220514B: MAXI/GSC detection
  64. MAXI GRB220514.98: Global MASTER-Net observations report
  65. Integral GRB220514.52: Global MASTER-Net observations report
  66. Fermi GRB 220514A: Global MASTER-Net observations report
  67. Fermi GRB 220513A: Global MASTER-Net observations report
  68. Konus-Wind detection of GRB 220511A
  69. GRB 220511A: Swift/BAT-GUANO arcminute localization
  70. GRB 220511A: AGILE detection
  71. Fermi trigger No 673846271: Global MASTER-Net observations report
  72. GRB 220506A: MITSuME Akeno optical upper limits
  73. GRB 220506A: GIT optical upper limit.
  74. GRB 220506A: BOOTES-5/JGT optical upper limit
  75. GRB 220506A: Swift-XRT afterglow detection
  76. GRB 220506A: Tiled Swift observations
  77. Swift GRB220506.51: Global MASTER-Net observations report
  78. GRB 220506A/MAXI J1558-266: MAXI/GSC detection
  79. MAXI GRB220506.27: Global MASTER-Net observations report
  80. GRB 220427A: LCO Optical Observations
  81. GRB 220501A: Swift-BAT refined analysis
  82. GRB 220426A: Swift-XRT and UVOT observations
  83. Fermi GRB 220426A: Global MASTER-Net observations report
  84. Fermi GRB 220426B: Global MASTER-Net observations report
  85. Fermi trigger No 672492774: Global MASTER-Net observations report
  86. IceCube Alert 220424.05: Global MASTER-Net observations report
  87. GRB 220421A: Fermi GBM observation
  88. Fermi trigger No 672093919: Global MASTER-Net observations report
  89. IPN triangulation of GRB 220411A
  90. GRB 220408A: Swift-BAT refined analysis
  91. GRB 220408A: 1.3m DFOT Optical upper limit
  92. GRB 220408A: LOAO, DOAO, and, SAO optical upper limit
  93. GRB 220408A: LCO Optical Afterglow Detection
  94. Fermi GRB 220408B: Global MASTER-Net observations report
  95. GRB 220408A: Fermi GBM observation
  96. Fermi-LAT Gamma-ray Observations of IceCube-220405A
  97. IceCube-220405A - IceCube observation of a high-energy neutrino candidate track-like event
  98. Fermi GRB 220401B: Global MASTER-Net observations report
  99. Fermi GRB 220330A: Global MASTER-Net observations report
  100. GRB 220325A: Swift-BAT refined analysis

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