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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"

27974 results found.

  1. GRB 210104B: Nanshan/NEXT optical upper limit
  2. GRB 210104B: BOOTES network optical upper limit
  3. GRB 210104A: MASTER OT rebrightening detection
  4. GRB 210104A: Swift/UVOT Detection
  5. GRB 210104A: Fermi GBM detection
  6. GRB 210104A: Enhanced Swift-XRT position
  7. GRB 210102B: Tiled Swift observations
  8. GRB 210104B: Swift detection of a burst
  9. Swift GRB210104.88: Global MASTER-Net observations report
  10. GRB 210104A: MITSuME Ishigaki optical observation
  11. GRB 210104A: MITSuME Akeno optical observation
  12. GRB 210104A: BOOTES-4/MET early optical afterglow detection
  13. GRB 210104A: Swift detection of a burst with a bright optical counterpart
  14. GRB 210104A: Fermi GBM Final Real-time Localization
  15. GRB 210102C: Swift-BAT refined analysis
  16. GRB 210102B: Swift-XRT observations
  17. GRB 210102C: Fermi GBM detection
  18. Swift GRB 210102C: Global MASTER-Net observations report
  19. GRB 210102C: Swift detection of a burst
  20. GRB 210102B: Tiled Swift observations
  21. GRB 210102B: MAXI/GSC detection
  22. Swift Trigger 1015615 is not a GRB
  23. Swift GRB210102.01: Global MASTER-Net observations report
  24. GRB 210101A: Fermi GBM Final Real-time Localization
  25. GRB 201229A: Swift/UVOT Detection
  26. GRB 201227A: GRAWITA VST-ESO PARANAL observations
  27. GRB 201229A: AbAO optical afterglow detection, TSHAO optical upper limit
  28. GRB 201229A: SAO RAS optical observations
  29. GRB 201229A: Nanshan/NEXT optical upper limit
  30. GRB 201227A: Swift-XRT observations
  31. GRB 201223A: SVOM-GWAC detected the optical counterpart during prompt emission phase
  32. GRB 201229A: Swift-XRT refined Analysis
  33. GRB 201229A: Swift-BAT refined analysis
  34. Konus-Wind observation of GRB 201227A
  35. GRB 201229B: Fermi GBM Final Real-time Localization
  36. GRB 201229A: Enhanced Swift-XRT position
  37. GRB 201229A: Swift detection of a burst with a possible optical counterpart
  38. GRB 201228B: Fermi GBM Final Real-time Localization
  39. GRB 201227A: Insight-HXMT/HE detection
  40. GRB 201226A: Insight-HXMT/HE detection
  41. GRB 201227A: Tiled Swift observations
  42. GRB 201227A: Swift ToO observations
  43. GRB 201228A: Fermi GBM Final Real-time Localization
  44. IPN triangulation of GRB 201227A (short)
  45. GRB 201223A: AROMA-N Optical Observation
  46. GRB 201227A: AGILE detection of a burst
  47. GRB 201223A: Swift/UVOT Detection
  48. GRB 201223A: HCT optical upper limit
  49. GRB 201223A: 1.3m DFOT and 1.04m ST optical observations
  50. GRB 201223A: Swift-XRT refined Analysis
  51. GRB 201223A: Enhanced Swift-XRT position
  52. GRB 201223A: GROWTH-India Telescope (GIT) photometric follow-up.
  53. GRB 201223A: MITSuME Akeno optical observation
  54. GRB 201223A: Swift-BAT refined analysis
  55. GRB 201223A: Fermi GBM Detection
  56. GRB 201223A: BOOTES-4/MET early optical observation
  57. GRB 201223A: Nanshan/NEXT early optical afterglow detection
  58. GRB 201223A: Swift detection of a burst with a bright optical counterpart
  59. Swift GRB201223.75: Global MASTER-Net OT detection
  60. Swift GRB201223.75: Global MASTER-Net observations report
  61. Swift-XRT observations of Icecube 201222A
  62. IceCube-201222A: No significant detection in HAWC
  63. IceCube-201221A: No significant detection in HAWC
  64. GRB 201221A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  65. GRB 201221A: REM early-time afterglow detection
  66. GRB 201221B: Insight-HXMT/HE detection
  67. GRB 201221D: MMT MMIRS detection of marginally extended source
  68. GRB 201221D: LCOGT upper limits
  69. GRB 201221D: Fermi GBM detection
  70. GRB 201221D: Swift-BAT refined analysis
  71. Swift Trigger 1014012 (possible GRB 201221C) is likely not an astrophysical event
  72. GRB 201216A - further Swift-XRT observations
  73. GRB 201221D: Archival PS1 Imaging of the Putative Host Galaxy
  74. Konus-Wind detection of GRB 201221D (short)
  75. GRB 201221D: Swift/UVOT Upper Limits
  76. GRB 201221D: Lowell Discovery Telescope afterglow observations
  77. GRB 201222B: Fermi GBM Final Real-time Localization
  78. GRB 201221D: FRAM-ORM optical limit
  79. GRB 201221D: Swift-XRT refined Analysis
  80. Swift GRB 201221D: Global MASTER-Net observations report
  81. IceCube-201222A: IceCube observation of a high-energy neutrino candidate event
  82. GRB 201221D: Enhanced Swift-XRT position
  83. GRB 201221A: Swift-BAT refined analysis
  84. GRB 201222A: Fermi GBM Final Real-time Localization
  85. GRB 201221E: Fermi GBM Final Real-time Localization
  86. GRB 201221D: Prompt enhanced Swift-XRT position
  87. GRB 201221D: Swift detection of a bright short burst
  88. correction to GCN 29110 - Fermi GBM Sub-Threshold Detection of GRB 201221A
  89. Fermi GBM Sub-Threshold Detection of GRB 201221A
  90. GRB 201221A: Swift/UVOT Upper Limits
  91. GRB 201221A: Swift-XRT refined Analysis
  92. GRB 201221C: MASTER optical observtion
  93. Swift Trigger 1014012: possible GRB 201221C
  94. GRB 201221A: Enhanced Swift-XRT position
  95. IceCube-201221A: IceCube observation of a high-energy neutrino candidate event
  96. GRB 201221B: Fermi GBM Final Real-time Localization
  97. GRB 201221A: FRAM-Auger optical limit
  98. Swift GRB 201221A: Global MASTER-Net observations report
  99. GRB 201221A: Prompt enhanced Swift-XRT position
  100. GRB 201221A: Swift detection of a burst

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