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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"

19670 results found.

  1. GRB 201104A: Swift-XRT observations
  2. Swift XRT and UVOT detection of ZTF20acozryr/AT2020yxz/GRB201103B
  3. GRB 201015A: Swift-XRT late time observations
  4. Correction to GCN 28843: GBM report of GRB 201105B should have been GRB 201105A
  5. GRB 201104B: Swift/UVOT Detection
  6. GRB 201104B: Swift-XRT refined Analysis
  7. Correcton to GCN 28848: Swift observes ZTF20acozryr
  8. GRB 201104C: Swift ToO observations
  9. GRB 201105A: Swift detected burst and BAT refined analysis
  10. IPN triangulation of GRB 201103B (consistent with ZTF20acozryr/AT2020yxz)
  11. GRB 201104B: Swift-BAT refined analysis
  12. Swift Trigger 1004219: Detection of SGR 1830-0645
  13. GRB 201104A: Tiled Swift observations
  14. GRB 201104A: Fermi-LAT detection
  15. GRB 201104B: Swift/UVOT Detection
  16. GRB 201104B: MASTER optical observation
  17. GRB 201104B: Swift detection of a burst
  18. GRB 201015A: Late X-ray Detections with Chandra
  19. Swift GRB 201031A: Global MASTER-Net observations report
  20. Swift Trigger 1003313 (a.k.a. GRB 201031A) is not an astrophysical event
  21. GRB 201031A: Swift detection of a burst
  22. GRB 201029A: Swift-BAT refined analysis
  23. IceCube 201021A: Swift follow-up of Fermi J1725.5+1312
  24. Swift GRB 201029A: Global MASTER-Net observations report
  25. GRB 201029A: Swift/UVOT Upper Limits
  26. GRB 201029A: Fermi GBM detection
  27. GRB 201029A: Swift-XRT refined Analysis
  28. GRB 201029A: BOOTES-1 optical upper limit
  29. GRB 201029A: Enhanced Swift-XRT position
  30. GRB 201029A: FRAM-ORM optical limit
  31. GRB 201029A: Swift detection of a burst
  32. GRB 201027A: MITSuME Akeno optical upper limits
  33. GRB 201027A: Swift-BAT refined analysis
  34. GRB 201026A: Swift-BAT refined analysis
  35. GRB 201027A: Swift/UVOT Upper Limits
  36. GRB 201027A: Swift-XRT refined Analysis
  37. GRB 201026A: Fermi GBM detection
  38. GRB 201026A: Swift-XRT refined Analysis
  39. GRB 201027A: 1.5m OSN optical upper limit
  40. GRB 201026A: Swift/UVOT Upper Limits
  41. GRB 201027A: Enhanced Swift-XRT position
  42. GRB 201026A: Enhanced Swift-XRT position
  43. GRB 201027A: Swift detection of a burst
  44. Swift GRB201027.05: Global MASTER-Net observations report
  45. GRB 201026A: Swift detection of a burst
  46. Swift GRB201026.94: Global MASTER-Net observations report
  47. GRB 201024A: 1.3m DFOT optical observations
  48. GRB 201020B: 1.3m DFOT continued optical follow-up observations
  49. GRB201024A: correction to GCN28777 - there was no rebrightening
  50. GRB 201024A: Swift-BAT refined analysis
  51. GRB201024A: rebrightening after initial steep decline
  52. GRB 201024A: Swift-XRT refined Analysis
  53. GRB 201024A: Swift/UVOT Detection
  54. GRB 201020B: 1.3m DFOT optical observations
  55. GRB 201024A: Enhanced Swift-XRT position
  56. GRB 200901A: FRAM-Auger optical limit
  57. GRB 201024A: BOOTES-2/TELMA early optical observation and 1.5m OSN follow-up
  58. GRB 201024A: Swift detection of a burst with an optical afterglow
  59. Swift GRB201024A: Global MASTER-Net OT detection
  60. Swift GRB201024.12: Global MASTER-Net observations report
  61. GRB 201021C: Swift-BAT refined analysis
  62. GRB 201021C: Swift-XRT refined Analysis
  63. Fermi-LAT Gamma-ray Observations of IceCube-201021A and detection of a new gamma-ray source, Fermi J1725.5+1312
  64. Swift-XRT observations of IceCube 201021A (2)
  65. GRB 201021C: Fermi GBM detection
  66. GRB 201020A: GROWTH-India Telescope late-time optical upper limit
  67. GRB 201021C: Swift/UVOT Detection
  68. Konus-Wind detection of GRB 201020A
  69. GRB 201020B: Swift/UVOT Detection
  70. GRB 201020A: Swift/UVOT Observations
  71. GRB 201020B: Swift-XRT afterglow detection
  72. GRB 201021C: Enhanced Swift-XRT position
  73. GRB 201021C: MASTER optical synchronously observation
  74. Swift GRB201021.85: Global MASTER-Net observations report
  75. GRB 201021C: Swift detection of a burst with an optical counterpart
  76. Swift-XRT observations of IceCube 201021A
  77. GRB 201020B: Swift ToO observations
  78. GRB 201020A: Swift-XRT refined Analysis
  79. GRB 201020A: Fermi GBM observation
  80. GRB 201020A: Swift-BAT refined analysis
  81. Swift GRB 201020A: Global MASTER-Net observations report
  82. GRB 201014A: SAO RAS optical observations
  83. GRB 201020A: Enhanced Swift-XRT position
  84. GRB 201020A: Swift detection of a burst with an optical counterpart.
  85. GRB 201017A iTelescope observation
  86. GRB 201017A: GROWTH-India optical upper limit
  87. GRB 201014A: 3.6m DOT Optical Observations
  88. GRB 201013A: 3.6m DOT Optical Observations
  89. GRB 201014A: MMT afterglow detection
  90. GRB 201017A: MITSuME Akeno optical upper limits
  91. GRB 201017A: Swift-BAT refined analysis
  92. GRB 201015A: GROWTH-India Telescope (GIT) upper limit
  93. GRB 201015A: HCT optical photometric follow-up
  94. GRB 201017A: Assy and Mondy optical observations, possible afterglow detection
  95. GRB 201017A: Swift-XRT refined Analysis
  96. GRB 201015A: MMT afterglow imaging
  97. GRB 201017A: Fermi GBM detection
  98. GRB 201017A: Enhanced Swift-XRT position
  99. Trigger 1000631: Swift detection of Cen X-3
  100. GRB 201015A: classification as long GRB

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