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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"

14990 results found.

  1. GRB 210619B: ASIM observation
  2. GRB 210618A: Swift-XRT afterglow detection
  3. GRB 210622A: Fermi GBM detection
  4. GRB 210622A: Swift/BAT-GUANO detection and arcminute localization of a long burst
  5. GRB 210619B: possibility of lensed visible afterglow?
  6. GECAM detection of GRB 210622B
  7. GRB 210622B: Fermi GBM Final Real-time Localization
  8. GRB 210622A: Fermi GBM Final Real-time Localization
  9. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  10. GRB 210619B: 1.5m OSN optical observation
  11. GRB 210619B: REM optical/NIR afterglow detection
  12. GRB 210621A: Fermi GBM Final Real-time Localization
  13. GRB 210619B: CALET Gamma-Ray Burst Monitor detection
  14. GRB 210619B: SRG/ART-XC detection
  15. GRB 210619B: Fermi GBM detection
  16. GRB 210619B: Swift/UVOT Detection
  17. GRB 210619B: Xinglong TNT optical observations
  18. Konus-Wind detection of GRB 210619B
  19. GRB 210619B: CAHA 2.2m photometric monitoring
  20. GRB 210619B: Liverpool Telescope r'-band observations
  21. GRB 210619B: KAIT Optical Detection
  22. GRB 210619B: Fermi-LAT detection
  23. GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
  24. GRB 210619B: iTelescope T18 detection
  25. GECAM detection of GRB 210619B
  26. GRB 210619B: Ondrejov D50 detection
  27. Swift GRB210619.99: Global MASTER-Net OT detection
  28. GRB 210619B: Swift detection of a bright burst and optical counterpart
  29. Swift GRB210619.99: Global MASTER-Net OT detection
  30. GRB 210619A: Fermi GBM Final Real-time Localization
  31. GRB 210618A: BOOTES-2/TELMA optical upper limit
  32. GRB 210618A: Swift detection of a burst
  33. GRB 210618A: Fermi GBM Final Real-time Localization
  34. GRB 210610B: Swift/UVOT Detection
  35. GRB 210610A: Swift/UVOT Detection
  36. GRB 210615A: Fermi GBM Final Real-time Localization
  37. GRB 210605B: Swift-XRT afterglow detection
  38. GRB 210610B: Continued KAIT Optical Detection
  39. GRB 210421B: Fermi GBM detection
  40. GRB 210607C: AstroSat CZTI detection
  41. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  42. GRB210610B: SARA-KP 0.9m Optical Afterglow Detection
  43. GRB 210610B: VLA detection
  44. GRB 210610B: ALMA detection
  45. GRB 210606A: Fermi GBM detection
  46. GRB 210605B: Fermi GBM detection
  47. GRB 210610B: Zwicky Transient Facility afterglow detection
  48. GRB 210610B: KAIT Optical Detection
  49. GRB 210610A: KAIT Optical Detection
  50. GRB 210607C: Insight-HXMT/HE detection
  51. GRB 210610B: Fermi GBM detection
  52. Konus-Wind detection of GRB 210610A
  53. Konus-Wind detection of GRB 210610B
  54. GRB 210610B: AGILE detection
  55. GRB 210610B: GOTO confirmation of afterglow detection
  56. GRB 210610A: RATIR Optical and NIR Detection
  57. GRB 210610B: SAO RAS optical observations
  58. GRB 210610A: 1.5m OSN optical observation
  59. GRB210610B: MeerLICHT multi-colour photometry
  60. GRB 210610B: GIT optical detection
  61. Swift GRB210610.83: Global MASTER-Net OT detection
  62. GRB 210606A: Swift-XRT afterglow detection
  63. GRB 210610B: Swift detection of a burst with bright optical afterglow
  64. GRB210610A: MeerLICHT multi-colour photometry
  65. GRB 210610A: Xinglong-2.16m redshift
  66. GRB 210610A: GIT optical detection
  67. GRB 210610A: Xinglong-2.16m optical afterglow observations
  68. GRB 210610A: Swift detection of a burst with an optical counterpart
  69. GRB 210607B: Insight-HXMT/HE detection
  70. GRB 210605A: CALET Gamma-Ray Burst Monitor detection
  71. Konus-Wind detection of GRB 210606B
  72. IPN triangulation of GRB 210606B
  73. IceCube-210608A: IceCube observation of a high-energy neutrino candidate track-like event
  74. GRB 210607A/MAXI J1733-222: MAXI/GSC detection
  75. GRB 210606B: Fermi GBM detection
  76. Konus-Wind detection of GRB 210602A
  77. Konus-Wind detection of GRB 210605A (short/hard)
  78. IPN triangulation of GRB 210605A (short)
  79. GRB 210606B: AGILE detection
  80. GRB 210606A: 1.5m OSN optical upper limit
  81. GECAM Sub-Threshold Detection of new magnetar Swift SGR J1555.2-5402
  82. GRB 210606B: GECAM detection
  83. GRB 210606A: Swift/BAT-GUANO detection and arcminute localization
  84. GRB 210606A: Fermi GBM Final Real-time Localization
  85. GRB 210605B: Swift/BAT-GUANO detection and arcminute localization
  86. GRB 210605B: Fermi GBM Final Real-time Localization
  87. GRB 210605A: Fermi GBM Final Real-time Localization
  88. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  89. Swift Detection of probable new Swift SGR J1555.2-5402
  90. GRB 210602A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 210602B: GECAM detection
  92. GRB 210529A: GECAM detection
  93. GRB 210602A: MAXI/GSC detection
  94. GRB 210601A: Fermi GBM Final Real-time Localization
  95. IPN triangulation of GRB 210531A
  96. GRB210529B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 644025222)
  97. GRB 210531A: AstroSat CZTI detection
  98. GRB 210531A: AGILE/MCAL detection (Fermi Trigger 644155206 / GRB 210531500)
  99. GRB 210529B: Fermi GBM Final Real-time Localization
  100. GRB 210529A: Fermi GBM Final Real-time Localization

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