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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"

14990 results found.

  1. GRB 211107B: Swift-XRT afterglow detection
  2. GRB 211107A: GECAM detection
  3. GRB 211106A: Swift-XRT afterglow detection
  4. MeerLICHT follow-up of GRB 211106A
  5. GRB 211109C: GECAM detection
  6. GRB 211109B: Fermi GBM Final Real-time Localization
  7. GRB 211109A: Fermi GBM Final Real-time Localization
  8. GRB 211107B: Swift/BAT detection
  9. Fermi GBM Sub-Threshold Detection of GRB 211106A
  10. Konus-Wind detection of GRB 211106A
  11. GRB 211107A: Fermi GBM Final Real-time Localization
  12. GRB 211106A: Swift/BAT-GUANO candidate arcminute localization of a short burst
  13. GRB 211105A: Swift/BAT-GUANO detection outside the coded FOV
  14. GRB 211105A: GECAM detection
  15. Swift Trigger 1082569 is probably not a GRB
  16. GRB 211105A: AGILE detection of a burst
  17. GRB 211023A: optical detection by SBT in Ondrejov
  18. GRB 211104A: Fermi GBM Final Real-time Localization
  19. GRB 211024A: MITSuME Akeno optical observation
  20. GRB 211102B: GECAM detection
  21. GRB 211102B: Fermi GBM Final Real-time Localization
  22. GRB 211102A: Fermi GBM Final Real-time Localization
  23. GRB 211031A: Fermi GBM Final Real-time Localization
  24. IPN triangulation of GRB 211022A
  25. Konus-Wind detection of GRB 211023A
  26. GRB 211027A: Fermi GBM Final Real-time Localization
  27. GRB 211024A: Fermi GBM detection
  28. GRB 211025A: Optical Afterglow Detection
  29. GRB211023A: optical afterglow detection from Konkoly Observatory
  30. GRB 211024A: Swift/BAT-GUANO detection and candidate arcminute localization of a short burst
  31. GRB 211024B: Swift/UVOT detection
  32. GRB 211023B: LDT Optical Afterglow Detection
  33. Correction to GCN 30965: GRB 211023A: Fermi GBM detection
  34. GRB 211024B: CAHA 2.2m Detection; ultra-long GRB?
  35. IPN Triangulation of GRB 211019A
  36. Possible Short GRB 211023B: CAHA 2.2m Detection
  37. GRB 211025A: Swift/UVOT Detection
  38. GRB 211023A: 1.5m OSN optical observation
  39. GRB 211025A: Swift detection of a burst
  40. GECAM detection of a short burst probably from SGR J1555.2-5402
  41. GRB 211024B: Nanshan/NEXT optical afterglow detection
  42. GRB 211023A: OAJ Bright Afterglow Confirmation
  43. GRB 211024B: Swift detection of a burst
  44. GRB 211023A: MASTER OT J045237.07+851925.2 - optical counterpart discovery
  45. GRB 211023B: BOOTES-4/MET and 1.5m OSN optical upper limit
  46. GRB 211023B: Swift/UVOT Detection
  47. GRB 211024A: GECAM detection
  48. GRB 211023B: TSHAO optical observation
  49. IceCube-211023A: No neutrino counterpart detected with ANTARES
  50. GRB 211023A: AGILE detection
  51. GRB 211022A: AstroSat CZTI detection
  52. GRB 211023A: Fermi GBM detection
  53. GRB 211024A: Fermi GBM Final Real-time Localization
  54. GRB 211023A: Fermi-LAT detection
  55. GRB 211023B: Swift detection of a possibly short burst with an optical counterpart
  56. GRB 211023A: Fermi GBM Final Real-time Localization
  57. IceCube-211023A - IceCube observation of a high-energy neutrino candidate track-like event
  58. IPN Triangulation of GRB 210927B
  59. GRB 211022A: GECAM detection
  60. AMON IC_HAWC NuEm-211020A: No neutrino counterpart detected with ANTARES
  61. BepiColombo MGNS joins the IPN
  62. GRB 211019A: Detection by GRBAlpha
  63. GRB 211018A: Detection by GRBAlpha
  64. GRB 211018A: Fermi-LAT detection
  65. GRB 211019A: Fermi GBM Final Real-time Localization
  66. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  67. Swift Trigger 1078701 is probably not a GRB
  68. IceCube-20210922A: DESNU Optical counterpart candidate from 5 nights of DECam observations
  69. GRB 210928A: MeerKAT detection
  70. GECAM observation of a burst from SGR J1555.2-5402
  71. Konus-Wind detection of GRB 210928A
  72. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  73. GRB 210928A: Fermi-LAT detection
  74. GRB 210927B: GECAM detection
  75. GRB 210930A: CAHA 2.2m telescope optical limit
  76. Swift Trigger 1076121 is not a GRB
  77. Swift GRB211001.03: Global MASTER-Net OT detection
  78. GRB 210930A: Swift detection of a burst
  79. GRB 210929B: Fermi GBM Final Real-time Localization
  80. GRB 210929A: Fermi GBM Final Real-time Localization
  81. GRB 210927A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 654396242)
  82. GRB 210925B: AstroSat CZTI detection
  83. GRB 210926A: AstroSat CZTI detection
  84. IceCube-210926A: No neutrino counterpart candidates in ANTARES search
  85. GRB 210926A: GECAM detection
  86. GRB 210927A: Fermi GBM Final Real-time Localization
  87. GRB 210919A OSN 1.5m Source Confirmation
  88. GRB 210925A: GECAM detection
  89. GRB 210925A: Fermi GBM Final Real-time Localization
  90. GRB 210924A: Fermi GBM Final Real-time Localization
  91. IceCube-210922A: No significant detection in HAWC
  92. IceCube-210922A: No neutrino counterpart candidates in ANTARES search
  93. GRB 210923B: GECAM detection
  94. GECAM observations of a series of bursts from SGR J1935+2154 (2021-09-15T14 to 2021-09-23T14)
  95. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 September 22
  96. GRB 210923A: Fermi GBM Final Real-time Localization
  97. IceCube-210922A - IceCube observation of a high-energy neutrino candidate track-like event
  98. GRB 210919B: Fermi GBM Final Real-time Localization
  99. GRB 210919A: LCO Optical Upper Limit
  100. GRB 210919A: BOOTES-2/TELMA optical upper limit

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