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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"

28280 results found.

  1. GRB 220430A: MeerLICHT optical upper limits
  2. GRB 220430A: Enhanced Swift-XRT position
  3. GRB 220430A: Swift detection of a burst or Swift J0630.4+0932
  4. GRB 220427A: VLT/X-shooter photometry
  5. GRB 220426A: Swift-XRT and UVOT observations
  6. GRB 220423A: Detection by VZLUSAT-2
  7. Konus-Wind detection of GRB 220427A
  8. GRB 220427A: Swift-XRT refined Analysis
  9. GRB 220427A: Enhanced Swift-XRT position
  10. GRB 220426A: Tiled Swift observations
  11. GRB 220427A: Swift detection of a burst with an optical counterpart
  12. Konus-Wind detection of GRB 220426A
  13. IPN triangulation of GRB 220426A
  14. GRB 220426C: Swift/BAT-GUANO detection outside the coded FOV (short)
  15. GRB 220426A: Fermi GBM detection
  16. GRB 220426A: Swift/BAT-GUANO detection outside the coded FOV
  17. GRB 220426B: Fermi GBM Final Real-time Localization
  18. Correction to 31937: GRB 220421B: Detection by VZLUSAT-2
  19. IceCube-220425A: MASTER: flaring blazar TXS 1742-078 as the possible neutrino source candidate
  20. IceCube-220425A - IceCube observation of a high-energy neutrino candidate track-like event
  21. GRB 220423A: Swift/BAT-GUANO detection outside the coded FOV
  22. IceCube-220424A - IceCube observation of a high-energy neutrino candidate track-like event
  23. On the AGILE detection of GRB 220423A
  24. GRB 220423A: AGILE detection
  25. GRB 220421B: Detection by VZLUSAT-2
  26. GRB 220421A: Swift/BAT-GUANO detection outside the coded FOV
  27. IceCube-220421A - IceCube observation of a high-energy neutrino candidate track-like event
  28. GRB 220418B: Swift-XRT observations
  29. GRB 220420A: Swift/BAT-GUANO detection outside the coded FOV
  30. GRB 220403C: Further Swift-XRT observations
  31. GRB 220418B: Swift ToO observations
  32. GRB 220417A: Fermi GBM detection
  33. IPN triangulation of GRB 220411A
  34. GRB 220418B: Swift/BAT-GUANO candidate arcminute localization of a short burst
  35. GRB 220417A: Swift/BAT-GUANO detection outside the coded FOV
  36. GRB 220412B: Swift/UVOT Upper Limits
  37. GRB 220418B: Fermi GBM Final Real-time Localization
  38. GRB 220418A: Fermi GBM Final Real-time Localization
  39. GRB 220417A: Fermi GBM Final Real-time Localization
  40. Konus-Wind detection of GRB 220412B
  41. Konus-Wind detection of GRB 220403C
  42. Konus-Wind detection of GRB 220408B
  43. GRB 220412B: TNG optical observations
  44. GRB 220412A: GRANDMA observations
  45. GRB 220412A: Continued RATIR Observations and Steepening of the Light Curve
  46. GRB 220412A: BOOTES-network optical upper limits
  47. GRB 220412B: BOOTES-1 optical upper limit
  48. GRB 220412A: RATIR Observations of the Fading Afterglow
  49. GRB 220412B: Swift-XRT observations
  50. GRB 220408B: Fermi-LAT detection
  51. GRB 220408A: HCT optical upper limit
  52. GRB 220412A: MITSuME Akeno optical upper limits
  53. Correction to GCN 31888: GRB 220412A: Swift-XRT refined Analysis
  54. GRB 220412A: Swift-XRT refined Analysis
  55. GRB 220412A: Enhanced Swift-XRT position
  56. GRB 220412B: Swift detection of a short burst
  57. GRB 220412A: Swift/UVOT Upper Limits
  58. GRB 220408A: GRANDMA observations
  59. GRB 220403B: GRANDMA observations
  60. GRB 220412A: RATIR Afterglow Candidate
  61. GRB 220412A: Swift detection of a burst
  62. GRB 220411A: AstroSat CZTI detection
  63. IPN triangulation of GRB 220408B
  64. IPN triangulation of GRB 220403C
  65. GRB 220403B: Swift/UVOT Detection
  66. GRB 220408A: Lowell Discovery Telescope Optical Observations
  67. GRB 220411A: Fermi GBM Final Real-time Localization
  68. GRB 220408A: RATIR Optical and NIR Observations
  69. GRB 220403B: 1.3m DFOT Optical upper limit
  70. GRB 220408A: 1.3m DFOT Optical upper limit
  71. GRB 220408A: LOAO, DOAO, and, SAO optical upper limit
  72. GRB 220403C: Swift-XRT observations
  73. GRB 220408A: NOT optical observations and archival detection
  74. GRB 220408B: AstroSat CZTI detection
  75. GRB 220408A: LCO Optical Afterglow Detection
  76. GRB 220408A: Swift-XRT refined Analysis
  77. GRB 220403C: Swift ToO observations
  78. GRB 220408A: BOOTES-5/JGT optical afterglow detection
  79. GRB 220408A: GIT optical upper limit
  80. GRB 220408A: Swift/UVOT Detection
  81. GRB 220408B: Fermi GBM Final Localization
  82. GRB 220408A: Enhanced Swift-XRT position
  83. GRB 220408A: KAIT Optical Observations
  84. GRB 220408A: Swift detection of a burst with an optical counterpart, possibly associated with M51
  85. GRB 220408A: Fermi GBM Final Real-time Localization
  86. GRB 220403B: Mondy optical upper limit
  87. GRB 220403B: 1.5m OSN optical observation
  88. IceCube-220405A - IceCube observation of a high-energy neutrino candidate track-like event
  89. GRB 220403B: Kitab optical observations
  90. GRB 220405A: Fermi GBM Final Localization
  91. IceCube-220405A - IceCube observation of a high-energy neutrino candidate track-like event
  92. GRB 220404B: Fermi GBM Final Real-time Localization
  93. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  94. GRB 220403B: Fermi GBM detection
  95. GRB 220404A: Swift detection of a burst
  96. GRB 220403B: Swift-XRT refined Analysis
  97. GRB 220403B: LBT observations
  98. GRB 220403C (or A): Swift/BAT-GUANO detection outside the coded FOV
  99. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  100. GRB 220403B: optical detection by D50

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