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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"

39455 results found.

  1. Fermi GRB 220513A: Global MASTER-Net observations report
  2. GRB 220513A: Fermi GBM Final Real-time Localization
  3. Konus-Wind detection of GRB 220511A
  4. GRB 220427A: MeerLICHT afterglow observations
  5. GRB 220511A: Fermi GBM observation
  6. GRB 220511A: Swift-XRT observations
  7. GRB 220511A: AstroSat CZTI detection
  8. GRB 220511A: BOOTES-2/TELMA optical upper limit
  9. Fermi GRB 220512A: Global MASTER-Net observations report
  10. GRB 220512A: Fermi GBM Final Real-time Localization
  11. GRB 220511A: Swift ToO observations
  12. GRB 220511A: Swift/BAT-GUANO arcminute localization
  13. Fermi GRB 220511A: Global MASTER-Net observations report
  14. GRB 220511A: AGILE detection
  15. GRB 220511A: BALROG localization (Fermi Trigger 673969321/ GRB 220511571)
  16. GRB 220511A: Fermi GBM Final Real-time Localization
  17. GRB 220507A: AstroSat CZTI detection
  18. Fermi-LAT Gamma-ray Observations of IceCube-220509A
  19. Fermi trigger No 673846271: Global MASTER-Net observations report
  20. GRB 220506A: MITSuME Akeno optical upper limits
  21. GRB 220506A: GIT optical upper limit.
  22. IceCube Alert 220509.76: Global MASTER-Net observations report
  23. GRB 220508A: Fermi GBM Final Real-time Localization
  24. GRB 220507A: Fermi GBM Final Localization
  25. GRB 220506A: BOOTES-5/JGT optical upper limit
  26. Fermi trigger No 673610950: Global MASTER-Net observations report
  27. GRB 220506A: Swift-XRT afterglow detection
  28. GRB 220506A: Tiled Swift observations
  29. Swift GRB220506.51: Global MASTER-Net observations report
  30. GRB 220506A/MAXI J1558-266: MAXI/GSC detection
  31. MAXI GRB220506.27: Global MASTER-Net observations report
  32. GRB 220430A: Nanshan/NEXT optical upper limit
  33. GRB 220430A: Nanshan/HMT optical upper limit
  34. GRB 220430A: GIT optical upper limits
  35. IPN triangulation of GRB 220423A
  36. GRB 220427A: LCO Optical Observations
  37. GRB 220501A: Swift-BAT refined analysis
  38. Fermi-LAT Gamma-ray Observations of IceCube-220501A
  39. GRB 220427A: GRANDMA Early Optical Afterglow Detection
  40. GRB 220501A: BOOTES-1 optical upper limit
  41. GRB 220501A: Fermi GBM observation
  42. GRB 220430A: AstroSat CZTI detection
  43. IceCube Alert 220501.95: Global MASTER-Net observations report
  44. GRB 220501A: GRANDMA/TJML Optical Observations
  45. GRB 220501A: Fermi GBM Final Real-time Localization
  46. GRB 220501A: Swift detection of a burst
  47. GRB 220430A: Swift-BAT refined analysis
  48. GRB 220430A: CAHA 2.2m telescope optical limit
  49. GRB 220430A: Swift-XRT refined Analysis
  50. Swift GRB 220430A: Global MASTER-Net observations report
  51. GRB 220430A: GRANDMA observations
  52. GRB 220430A: Mondy and AbAO optical upper limits
  53. GRB 220430A: AGILE detection
  54. GRB 220430A: MeerLICHT optical upper limits
  55. GRB 220430A: Enhanced Swift-XRT position
  56. GRB 220430A: Swift detection of a burst or Swift J0630.4+0932
  57. GRB 220427A: Swift-BAT refined analysis
  58. GRB 220427A: VLT/X-shooter photometry
  59. GRB 220426A: Swift-XRT and UVOT observations
  60. GRB 220423A: Detection by VZLUSAT-2
  61. Konus-Wind detection of GRB 220427A
  62. GRB 220427A: Swift-XRT refined Analysis
  63. GRB 220427A: Enhanced Swift-XRT position
  64. GRB 220426A: Tiled Swift observations
  65. GRB 220427A: Swift detection of a burst with an optical counterpart
  66. Konus-Wind detection of GRB 220426A
  67. IPN triangulation of GRB 220426A
  68. GRB 220426C: Swift/BAT-GUANO detection outside the coded FOV (short)
  69. Fermi GRB 220426A: Global MASTER-Net observations report
  70. GRB 220426A: Fermi GBM detection
  71. GRB 220426A: Swift/BAT-GUANO detection outside the coded FOV
  72. Fermi-LAT Gamma-ray Observations of IceCube-220425A
  73. Fermi GRB 220426B: Global MASTER-Net observations report
  74. GRB 220426B: Fermi GBM Final Real-time Localization
  75. GRB 220426A: BALROG localization (Fermi Trigger 672648596/ GRB 220426285)
  76. Correction to 31937: GRB 220421B: Detection by VZLUSAT-2
  77. IceCube-220425A: MASTER: flaring blazar TXS 1742-078 as the possible neutrino source candidate
  78. Fermi-LAT Gamma-ray Observations of IceCube-220424A
  79. IceCube Alert 220425.11: Global MASTER-Net observations report
  80. Fermi trigger No 672492774: Global MASTER-Net observations report
  81. IceCube-220425A - IceCube observation of a high-energy neutrino candidate track-like event
  82. GRB 220423A: Swift/BAT-GUANO detection outside the coded FOV
  83. IceCube-220424A - IceCube observation of a high-energy neutrino candidate track-like event
  84. IceCube Alert 220424.05: Global MASTER-Net observations report
  85. Fermi trigger No 672374264: Global MASTER-Net observations report
  86. On the AGILE detection of GRB 220423A
  87. GRB 220423A: AGILE detection
  88. GRB 220421B: Detection by VZLUSAT-2
  89. GRB 220421A: Fermi GBM observation
  90. Fermi-LAT Gamma-ray Observations of IceCube-220421A
  91. GRB 220421A: Swift/BAT-GUANO detection outside the coded FOV
  92. Fermi trigger No 672221879: Global MASTER-Net observations report
  93. Fermi GBM trigger 672128054/220420260 is not a GRB
  94. IceCube-220421A - IceCube observation of a high-energy neutrino candidate track-like event
  95. GRB 220418B: Swift-XRT observations
  96. IceCube Alert 220421.22: Global MASTER-Net observations report
  97. GRB 220418B Fermi GBM observation
  98. Fermi trigger No 672093919: Global MASTER-Net observations report
  99. “GRB 220420A” is not a GRB
  100. GRB 220420A: Swift/BAT-GUANO detection outside the coded FOV

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