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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"

21525 results found.

  1. GRB 201029A: Swift detection of a burst
  2. GRB 201027A: MITSuME Akeno optical upper limits
  3. GRB 201027A: Swift-BAT refined analysis
  4. GRB 201026A: Swift-BAT refined analysis
  5. GRB 201027A: Swift/UVOT Upper Limits
  6. GRB 201027A: Swift-XRT refined Analysis
  7. GRB 201026A: Fermi GBM detection
  8. GRB 201026A: Swift-XRT refined Analysis
  9. GRB 201027A: 1.5m OSN optical upper limit
  10. GRB 201026A: Swift/UVOT Upper Limits
  11. GRB 201027A: Enhanced Swift-XRT position
  12. GRB 201026A: Enhanced Swift-XRT position
  13. GRB 201026A: FRAM-ORM optical detection limit
  14. GRB 201020A: 1.3m DFOT, optical upper limits
  15. GRB 201027A: Swift detection of a burst
  16. Swift GRB201027.05: Global MASTER-Net observations report
  17. GRB 201026A: NanShan/NEXT-0.6m optical upper limit
  18. GRB 201026A: NOT optical upper limits
  19. GRB 201026A: Swift detection of a burst
  20. Swift GRB201026.94: Global MASTER-Net observations report
  21. GRB 201024A: 1.3m DFOT optical observations
  22. GRB 201020B: 1.3m DFOT continued optical follow-up observations
  23. GRB201024A: correction to GCN28777 - there was no rebrightening
  24. GRB 201024A: Swift-BAT refined analysis
  25. GRB201024A: rebrightening after initial steep decline
  26. GRB 201024A: Swift-XRT refined Analysis
  27. GRB 201024A: Swift/UVOT Detection
  28. GRB 201020B: 1.3m DFOT optical observations
  29. GRB 201024A: VIRT optical observations
  30. GRB 201024A: Enhanced Swift-XRT position
  31. GRB 200901A: FRAM-Auger optical limit
  32. GRB 201024A: BOOTES-2/TELMA early optical observation and 1.5m OSN follow-up
  33. GRB 201024A: MASTER correction to GCN 28760
  34. GRB 201024A: Swift detection of a burst with an optical afterglow
  35. Swift GRB201024A: Global MASTER-Net OT detection
  36. Swift GRB201024.12: Global MASTER-Net observations report
  37. GRB 201021C: Swift-BAT refined analysis
  38. GRB 201021C: Swift-XRT refined Analysis
  39. Fermi-LAT Gamma-ray Observations of IceCube-201021A and detection of a new gamma-ray source, Fermi J1725.5+1312
  40. Swift-XRT observations of IceCube 201021A (2)
  41. GRB 201021C: Fermi GBM detection
  42. GRB 201020A: GROWTH-India Telescope late-time optical upper limit
  43. GRB 201021C: Swift/UVOT Detection
  44. Konus-Wind detection of GRB 201020A
  45. GRB 201020B: Swift/UVOT Detection
  46. GRB 201020A: Swift/UVOT Observations
  47. GRB 201014A: 2.0m HCT upper limit
  48. GRB 201020B: Swift-XRT afterglow detection
  49. GRB 201020A: VIRT optical observations
  50. GRB 201021C: Enhanced Swift-XRT position
  51. GRB 201021C: MASTER optical synchronously observation
  52. Swift GRB201021.85: Global MASTER-Net observations report
  53. GRB 201021C: Swift detection of a burst with an optical counterpart
  54. Swift-XRT observations of IceCube 201021A
  55. GRB 201020B: Swift ToO observations
  56. GRB 201020A: Swift-XRT refined Analysis
  57. GRB 201020A: Fermi GBM observation
  58. GRB 201020A: Swift-BAT refined analysis
  59. Swift GRB 201020A: Global MASTER-Net observations report
  60. GRB 201014A: SAO RAS optical observations
  61. GRB 201020A: Enhanced Swift-XRT position
  62. GRB 201020A: Swift detection of a burst with an optical counterpart.
  63. GRB 201017A iTelescope observation
  64. GRB 201017A: SAO RAS optical observations
  65. GRB 201017A: GROWTH-India optical upper limit
  66. GRB 201014A: 3.6m DOT Optical Observations
  67. GRB 201015A: 6 GHz VLA radio afterglow candidate detection
  68. GRB 201013A: 3.6m DOT Optical Observations
  69. GRB 201014A: MMT afterglow detection
  70. GRB 201017A: MITSuME Akeno optical upper limits
  71. GRB 201017A: Swift-BAT refined analysis
  72. GRB 201015A: GROWTH-India Telescope (GIT) upper limit
  73. GRB 201015A: HCT optical photometric follow-up
  74. GRB 201017A: Assy and Mondy optical observations, possible afterglow detection
  75. GRB 201017A: Swift-XRT refined Analysis
  76. GRB 201015A: MMT afterglow imaging
  77. GRB 201017A: Fermi GBM detection
  78. GRB 201017A: Xinglong TNT upper limit
  79. GRB 201017A: Enhanced Swift-XRT position
  80. Trigger 1000631: Swift detection of Cen X-3
  81. GRB 201015A: classification as long GRB
  82. Swift GRB 201017A: Global MASTER-Net observations report
  83. GRB 201017A: Swift detection of a burst
  84. Fermi GBM Sub-Threshold Detection of GRB 201015A
  85. GRB 201015A: Swift/UVOT Detection
  86. GRB 201015A: Swift-XRT refined Analysis
  87. MAGIC observations of GRB 201015A: hint of very high energy gamma-ray signal
  88. GRB 201015A: Swift-BAT refined analysis (a soft short pulse with a tail emission)
  89. GRB 201014A: Nanshan/NEXT optical observations
  90. GRB 201014A: Lowell Discovery Telescope afterglow imaging
  91. Konus-Wind observation of GRB 201013A
  92. GRB 201008A: Swift-XRT afterglow detection
  93. GRB 201015A: Enhanced Swift-XRT position
  94. GRB 201015A: BOOTES-1 early optical afterglow detection
  95. GRB 201014A: Swift/UVOT Upper Limits
  96. GRB 201015A: GOTO confirmation of afterglow detection
  97. GRB 201014A: Swift-XRT refined Analysis
  98. GRB 201015A: NOT optical afterglow confirmation
  99. GRB 201015A: Swift-XRT observations
  100. Swift GRB 201015A: Global MASTER-Net observations report

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