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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"

24619 results found.

  1. GRB 211110A: GECAM detection
  2. Fermi trigger No 658214822: Global MASTER-Net observations report
  3. GRB 211107A: GECAM detection
  4. GRB 211106A: VLT/FORS2 optical observations
  5. Fermi GRB 211109B: Global MASTER-Net observations report
  6. GRB 211107B: Swift-XRT observations
  7. GRB 211109C: GECAM detection
  8. GRB 211109B: Fermi GBM Final Real-time Localization
  9. Fermi GRB 211109A: Global MASTER-Net observations report
  10. GRB 211109A: Fermi GBM Final Real-time Localization
  11. GRB 211107B: Swift/BAT detection
  12. Konus-Wind detection of GRB 211106A
  13. GRB 211107A: Fermi GBM Final Real-time Localization
  14. GRB 211106A: Swift-XRT observations
  15. GRB 211106A: Swift/BAT-GUANO candidate arcminute localization of a short burst
  16. GRB 211105A: MASTER optical inspection
  17. GRB 211105A: Swift/BAT-GUANO detection outside the coded FOV
  18. GRB 211105A: GECAM detection
  19. GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
  20. Fermi trigger No 657742914: Global MASTER-Net observations report
  21. GRB 211104A: Fermi GBM Final Real-time Localization
  22. GRB 211023B: Subaru optical observation
  23. GRB 211024A: MITSuME Akeno optical observation
  24. GCN Viewer Now Available
  25. GRB 211102B: GECAM detection
  26. Fermi GRB 211102A: Global MASTER-Net observations report
  27. GRB 211102B: BALROG localization (Fermi Trigger 657554740 / GRB 211102587)
  28. GRB 211102B: Fermi GBM Final Real-time Localization
  29. GRB 211023B: MITSuME Akeno optical upper limits
  30. GRB 211102A: BALROG localization (Fermi Trigger 657533168 / GRB 211102338)
  31. GRB 211102A: Fermi GBM Final Real-time Localization
  32. GRB 211024B: Optical afterglow observation by Ondrejov D50
  33. Fermi GRB 211031A: Global MASTER-Net observations report
  34. GRB 211031A: Fermi GBM Final Real-time Localization
  35. IPN triangulation of GRB 211022A
  36. GRB 211023A: 1.3m DFOT Optical Observations
  37. Konus-Wind detection of GRB 211023A
  38. GRB 211023B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  39. Fermi GRB 211027A: Global MASTER-Net observations report
  40. GRB 211024A: Swift-XRT observations
  41. GRB 211027A: Fermi GBM Final Real-time Localization
  42. GRB 211024A: Fermi GBM detection
  43. GRB 211018A: Swift-XRT observations
  44. GRB 211025A: Optical Afterglow Detection
  45. GRB 211024A: Swift/BAT-GUANO detection and candidate arcminute localization of a short burst
  46. GRB 211023B: Gemini-North Optical Observations
  47. Swift GRB 211025A: Global MASTER-Net observations report
  48. IceCube-211023A: Upper limits from a search for additional neutrino events in IceCube
  49. GRB 211025A: Swift-BAT refined analysis
  50. GRB 211025A: Swift-XRT refined Analysis
  51. GRB 211024B: CAHA 2.2m Detection; ultra-long GRB?
  52. GRB 211024B: Swift-XRT refined Analysis
  53. IPN Triangulation of GRB 211019A
  54. GRB 211024B: Swift-BAT refined analysis
  55. GRB 211025A: Swift detection of a burst
  56. GECAM detection of a short burst probably from SGR J1555.2-5402
  57. Swift GRB 211024B: Global MASTER-Net observations report
  58. GRB 211023B: Swift-BAT refined analysis
  59. Fermi-LAT Gamma-ray Observations of IceCube-211023A
  60. GRB 211024A: GECAM detection
  61. IceCube-211023A: No neutrino counterpart detected with ANTARES
  62. Fermi GRB 211023A: Global MASTER-Net observations report
  63. GRB 211023A: AGILE detection
  64. GRB 211023A: Fermi GBM detection
  65. Swift GRB 211023B: Global MASTER-Net observations report
  66. Fermi GRB 211024A: Global MASTER-Net observations report
  67. GRB 211024A: Fermi GBM Final Real-time Localization
  68. GRB 211023A: Fermi-LAT detection
  69. IceCube Alert 211023.36: Global MASTER-Net observations report
  70. GRB 211023A: Fermi GBM Final Real-time Localization
  71. IceCube-211023A - IceCube observation of a high-energy neutrino candidate track-like event
  72. GRB 211022A: GECAM detection
  73. AMON IC_HAWC NuEm-211020A: No neutrino counterpart detected with ANTARES
  74. GRB 211021A: BALROG localization (Fermi Trigger 656506979 / GRB 211021460)
  75. Fermi trigger No 656506979: Global MASTER-Net observations report
  76. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-211020A
  77. BepiColombo MGNS joins the IPN
  78. Fermi trigger No 656268212: Global MASTER-Net observations report
  79. GRB 211018A: Fermi GBM observation
  80. GRB 211019A: Detection by GRBAlpha
  81. Fermi GRB 211019A: Global MASTER-Net observations report
  82. GRB 211018A: Fermi-LAT detection
  83. GRB 211019A: BALROG localization (Fermi Trigger 656315976 / GRB 211019250)
  84. GRB 211019A: Fermi GBM Final Real-time Localization
  85. Fermi trigger No 656288898: Global MASTER-Net observations report
  86. Swift GRB211017.99: Global MASTER-Net observations report
  87. Integral GRB211016.42: Global MASTER-Net observations report
  88. Swift trigger 1078701: MITSuME Akeno optical upper limits
  89. Fermi trigger No 655673024: Global MASTER-Net observations report
  90. GRB 210919A: LDT optical observations and candidate host galaxies
  91. IceCube-20210922A: No optical counterparts found by MITSuME observations
  92. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  93. Fermi trigger No 655646385: Global MASTER-Net observations report
  94. Swift GRB211010.45: Global MASTER-Net observations report
  95. IceCube-20210922A: DESNU Optical counterpart candidate from 5 nights of DECam observations
  96. GRB 211008A: BALROG localization (Fermi Trigger 655401471 / GRB 211008665)
  97. Fermi trigger No 655401471: Global MASTER-Net observations report
  98. GECAM observation of a burst from SGR J1555.2-5402
  99. Konus-Wind detection of GRB 210928A
  100. Fermi trigger No 654854799: Global MASTER-Net observations report

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