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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"

27940 results found.

  1. GRB 220107B: Tiled Swift observations
  2. GRB 220107A: Fermi GBM observations
  3. GRB 220107A: Swift ToO observations
  4. GRB 220107A: Swift/BAT-GUANO arcminute localization
  5. GRB 220101A: Tautenburg observations
  6. GRB 220107A: Fermi GBM Final Real-time Localization
  7. GRB 220101A: Continued Mondy optical observations
  8. GECAM detection of a short burst from SGR 1935+2154
  9. GRB 220101A: Mondy optical observations
  10. GRB 220101A: 3rd LCO Optical Observation
  11. GRB 220101A: 2.2m CAHA (+CAFOS) first day optical detection
  12. GRB 220101A: VLA detection
  13. GRB 220101A: 1.3m DFOT observations
  14. GRB 220101A: LCO Continued Optical Observations
  15. GRB 220104A:GECAM detection
  16. GRB 220104A: Fermi GBM Final Real-time Localization
  17. GRB 211229B: Fermi GBM observation
  18. GRB 220103A: Fermi GBM Final Real-time Localization
  19. GRB 211229B: Swift/BAT-GUANO detection outside the coded FOV
  20. GRB 220101A: TNG NIR afterglow detection
  21. GRB 220101A: ALMA detection
  22. GRB 220101A: LCO Optical Observations
  23. GRB 220101A: Swift-BAT refined analysis
  24. GRB 211231A: AstroSat CZTI detection
  25. GRB 220101A: OASDG optical observations
  26. GRB 220101A : Eiso equals the maximum isotropic GRB energy
  27. GRB 220101A: Asiago spectroscopic and photometric detection
  28. GRB220101A: optical afterglow detection from Konkoly Observatory
  29. GRB 220101A: Fermi GBM Detection
  30. GRB 220101A: CAHA 2.2m/CAFOS detection
  31. GRB 220101A: Swift-XRT refined Analysis
  32. GRB 220101A: AGILE detection
  33. GRB 220101A: Xinglong-2.16m photometry and spectroscopy
  34. Swift GRB220101.22: Global MASTER-Net observations report
  35. GRB 220101: Swift/UVOT Detection
  36. GRB 220101A: Fermi-LAT detection
  37. GRB 220101A: Enhanced Swift-XRT position
  38. GRB 220101A: Swift detection of a burst with a bright optical counterpart
  39. IPN triangulation of GRB 211219A
  40. GRB 211231A: GECAM detection
  41. GRB 211229B: AGILE detection
  42. GRB 211231A: Fermi GBM Final Real-time Localization
  43. GRB 211229A: Swift-XRT and UVOT observations
  44. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  45. GRB 211229A: Fermi GBM observation
  46. GRB 211229B: GECAM detection
  47. GRB 211229C: Swift/BAT-GUANO detection likely outside the coded FOV
  48. GRB 211229B: Fermi GBM Final Real-time Localization
  49. GRB 211229A: Swift ToO observations
  50. GRB 211229A: Swift/BAT-GUANO arcminute localization
  51. GRB 211227A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 211225B: CALET Gamma-Ray Burst Monitor detection
  53. GRB 211229A: GECAM detection
  54. GRB 211229A: Fermi GBM Final Real-time Localization
  55. GRB 211227A: Swift/UVOT Upper Limits
  56. GRB 211227A: Swift-XRT refined Analysis
  57. GRB 211227A: Swift-BAT refined analysis
  58. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  59. GRB 211227A: Enhanced Swift-XRT position
  60. GRB 211227A: LCO Optical Observations
  61. GRB 211227A: Nanshan/NEXT optical observations and host galaxy candidate
  62. GRB 211227A: MAXI/GSC detection
  63. GRB 211227A: BOOTES-2/TELMA optical upper limit
  64. GRB 211221A: Swift/UVOT Upper Limits
  65. GRB 211227A: Swift detection of a burst
  66. Swift GRB211227.98: Global MASTER-Net observations report
  67. GRB 211226A: Swift/BAT-GUANO detection outside the coded FOV
  68. GRB 211225B: Swift-BAT refined analysis
  69. GRB 211226A: AGILE/MCAL detection of a burst
  70. Swift GRB 211225B: Global MASTER-Net observations report
  71. GRB 211225C: Fermi GBM Final Real-time Localization
  72. GRB 211225B: Swift detection of a burst
  73. GRB 211225A/MAXI J0827-071: MAXI/GSC detection
  74. GRB 211224A: Fermi GBM Final Real-time Localization
  75. GRB 211211A: observations with the 3.6m Devasthal Optical Telescope
  76. GRB 211223C: Swift-BAT refined analysis
  77. GRB 211223C: BOOTES-4/MET optical upper limit
  78. Swift GRB 211223C: Global MASTER-Net observations report
  79. GRB 211223A: Insight-HXMT/HE detection
  80. Fermi GBM Sub-Threshold Detection of GRB 211221A
  81. Fermi GBM Sub-Threshold Detection of GRB 211207A
  82. GRB 211221A: Swift-BAT refined analysis
  83. GRB 211223C: Swift detection of a burst
  84. GRB 211223B: Fermi GBM Final Real-time Localization
  85. GRB 211223A: GECAM detection
  86. GRB 211219B: AstroSat CZTI detection
  87. GRB 211219A: AstroSat CZTI detection
  88. GRB 211221A: Swift-XRT refined Analysis
  89. GRB 211222A: Fermi GBM Final Real-time Localization
  90. GRB 211221A: BOOTES-4/MET optical upper limit
  91. GRB 211221A: MeerLICHT optical limits
  92. GRB 211221A: Enhanced Swift-XRT position
  93. Swift GRB 211221A: Global MASTER-Net observations report
  94. GRB 211221A: Swift detection of a burst
  95. IceCube-211216B: No significant detection in HAWC
  96. IceCube-211216A: No significant detection in HAWC
  97. GRB 211219A: AGILE detection
  98. GRB 211219A: Swift/BAT-GUANO detection outside the coded FOV
  99. GRB 211219B: Fermi GBM Final Real-time Localization
  100. GRB 211219A: Fermi GBM Final Real-time Localization

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