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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

39444 results found.

  1. GRB 220511A: Swift/BAT-GUANO arcminute localization
  2. Fermi GRB 220511A: Global MASTER-Net observations report
  3. GRB 220511A: AGILE detection
  4. GRB 220511A: BALROG localization (Fermi Trigger 673969321/ GRB 220511571)
  5. GRB 220511A: Fermi GBM Final Real-time Localization
  6. GRB 220507A: AstroSat CZTI detection
  7. Fermi-LAT Gamma-ray Observations of IceCube-220509A
  8. Fermi trigger No 673846271: Global MASTER-Net observations report
  9. GRB 220506A: MITSuME Akeno optical upper limits
  10. GRB 220506A: GIT optical upper limit.
  11. IceCube Alert 220509.76: Global MASTER-Net observations report
  12. GRB 220508A: Fermi GBM Final Real-time Localization
  13. GRB 220507A: Fermi GBM Final Localization
  14. GRB 220506A: BOOTES-5/JGT optical upper limit
  15. Fermi trigger No 673610950: Global MASTER-Net observations report
  16. GRB 220506A: Swift-XRT afterglow detection
  17. GRB 220506A: Tiled Swift observations
  18. Swift GRB220506.51: Global MASTER-Net observations report
  19. GRB 220506A/MAXI J1558-266: MAXI/GSC detection
  20. MAXI GRB220506.27: Global MASTER-Net observations report
  21. GRB 220430A: Nanshan/NEXT optical upper limit
  22. GRB 220430A: Nanshan/HMT optical upper limit
  23. GRB 220430A: GIT optical upper limits
  24. IPN triangulation of GRB 220423A
  25. GRB 220427A: LCO Optical Observations
  26. GRB 220501A: Swift-BAT refined analysis
  27. Fermi-LAT Gamma-ray Observations of IceCube-220501A
  28. GRB 220427A: GRANDMA Early Optical Afterglow Detection
  29. GRB 220501A: BOOTES-1 optical upper limit
  30. GRB 220501A: Fermi GBM observation
  31. GRB 220430A: AstroSat CZTI detection
  32. IceCube Alert 220501.95: Global MASTER-Net observations report
  33. GRB 220501A: GRANDMA/TJML Optical Observations
  34. GRB 220501A: Fermi GBM Final Real-time Localization
  35. GRB 220501A: Swift detection of a burst
  36. GRB 220430A: Swift-BAT refined analysis
  37. GRB 220430A: CAHA 2.2m telescope optical limit
  38. GRB 220430A: Swift-XRT refined Analysis
  39. Swift GRB 220430A: Global MASTER-Net observations report
  40. GRB 220430A: GRANDMA observations
  41. GRB 220430A: Mondy and AbAO optical upper limits
  42. GRB 220430A: AGILE detection
  43. GRB 220430A: MeerLICHT optical upper limits
  44. GRB 220430A: Enhanced Swift-XRT position
  45. GRB 220430A: Swift detection of a burst or Swift J0630.4+0932
  46. GRB 220427A: Swift-BAT refined analysis
  47. GRB 220427A: VLT/X-shooter photometry
  48. GRB 220426A: Swift-XRT and UVOT observations
  49. GRB 220423A: Detection by VZLUSAT-2
  50. Konus-Wind detection of GRB 220427A
  51. GRB 220427A: Swift-XRT refined Analysis
  52. GRB 220427A: Enhanced Swift-XRT position
  53. GRB 220426A: Tiled Swift observations
  54. GRB 220427A: Swift detection of a burst with an optical counterpart
  55. Konus-Wind detection of GRB 220426A
  56. IPN triangulation of GRB 220426A
  57. GRB 220426C: Swift/BAT-GUANO detection outside the coded FOV (short)
  58. Fermi GRB 220426A: Global MASTER-Net observations report
  59. GRB 220426A: Fermi GBM detection
  60. GRB 220426A: Swift/BAT-GUANO detection outside the coded FOV
  61. Fermi-LAT Gamma-ray Observations of IceCube-220425A
  62. Fermi GRB 220426B: Global MASTER-Net observations report
  63. GRB 220426B: Fermi GBM Final Real-time Localization
  64. GRB 220426A: BALROG localization (Fermi Trigger 672648596/ GRB 220426285)
  65. Correction to 31937: GRB 220421B: Detection by VZLUSAT-2
  66. IceCube-220425A: MASTER: flaring blazar TXS 1742-078 as the possible neutrino source candidate
  67. Fermi-LAT Gamma-ray Observations of IceCube-220424A
  68. IceCube Alert 220425.11: Global MASTER-Net observations report
  69. Fermi trigger No 672492774: Global MASTER-Net observations report
  70. IceCube-220425A - IceCube observation of a high-energy neutrino candidate track-like event
  71. GRB 220423A: Swift/BAT-GUANO detection outside the coded FOV
  72. IceCube-220424A - IceCube observation of a high-energy neutrino candidate track-like event
  73. IceCube Alert 220424.05: Global MASTER-Net observations report
  74. Fermi trigger No 672374264: Global MASTER-Net observations report
  75. On the AGILE detection of GRB 220423A
  76. GRB 220423A: AGILE detection
  77. GRB 220421B: Detection by VZLUSAT-2
  78. GRB 220421A: Fermi GBM observation
  79. Fermi-LAT Gamma-ray Observations of IceCube-220421A
  80. GRB 220421A: Swift/BAT-GUANO detection outside the coded FOV
  81. Fermi trigger No 672221879: Global MASTER-Net observations report
  82. Fermi GBM trigger 672128054/220420260 is not a GRB
  83. IceCube-220421A - IceCube observation of a high-energy neutrino candidate track-like event
  84. GRB 220418B: Swift-XRT observations
  85. IceCube Alert 220421.22: Global MASTER-Net observations report
  86. GRB 220418B Fermi GBM observation
  87. Fermi trigger No 672093919: Global MASTER-Net observations report
  88. “GRB 220420A” is not a GRB
  89. GRB 220420A: Swift/BAT-GUANO detection outside the coded FOV
  90. GRB 220403C: Further Swift-XRT observations
  91. GRB 220418B: Swift ToO observations
  92. GRB 220417A: Fermi GBM detection
  93. GRB 220418B: Swift/BAT-GUANO refined location of a short burst
  94. IPN triangulation of GRB 220411A
  95. GRB 220418B: Swift/BAT-GUANO candidate arcminute localization of a short burst
  96. GRB 220417A: Swift/BAT-GUANO detection outside the coded FOV
  97. GRB 220412B: Swift/UVOT Upper Limits
  98. Fermi GRB 220418A: Global MASTER-Net observations report
  99. GRB 220418B: Fermi GBM Final Real-time Localization
  100. GRB 220418A: Fermi GBM Final Real-time Localization

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