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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"

19662 results found.

  1. GRB 210901A: LCO Optical Upper Limit
  2. Swift GRB 210901A: Global MASTER-Net observations report
  3. GRB 210901A: Swift detection of a burst
  4. GRB 210827A: further Swift-XRT observations
  5. GRB 210822A: CALET Gamma-Ray Burst Monitor detection
  6. GRB 210827A: Swift/UVOT Upper Limits
  7. GRB 210827A: BOOTES-5/JGT optical upper limit
  8. GRB 210827A: Fermi GBM Observation
  9. GRB 210827A: Swift-XRT observations
  10. GRB 210827A: Swift ToO observations
  11. GRB 210827A: Swift/BAT-GUANO detection and arcminute localization
  12. GRB 210820A: CAHA 2.2m Optical Detection
  13. GRB 210824A: Swift/UVOT Upper Limits
  14. GRB 210826A: Swift/UVOT Upper Limits
  15. GRB 210826A: Swift-XRT observations
  16. GRB 210822A: CAHA 2.2m observations
  17. GRB 210824A: Swift-BAT refined analysis
  18. GRB 210826A: Fermi-LAT detection
  19. GRB 210826A: Tiled Swift observations
  20. Swift GRB210825.29: Global MASTER-Net observations report
  21. GRB 210822A: VLA detection
  22. Swift detection of an outburst from SGR Swift J1555.2-5402
  23. GRB 210822A: Swift/UVOT Detection
  24. Swift GRB 210824A: Global MASTER-Net observations report
  25. GRB 210824A: BOOTES-5/JGT optical upper limit
  26. GRB 210824A: Fermi GBM Observation
  27. GRB 210824A: Nanshan/NEXT optical upper limit
  28. GRB 210824A: Swift-XRT refined Analysis
  29. GRB 210822A: GROND observations
  30. GRB 210824A: Enhanced Swift-XRT position
  31. GRB 210824A: Swift detection of a burst
  32. GRB 210822A: Detection by GRBAlpha
  33. GRB 210822A: GECAM refined analysis
  34. GRB 210820A: GROND observations
  35. Konus-Wind detection of GRB 210822A
  36. GRB 210822A: AstroSat CZTI detection
  37. GRB 210822A: Swift-XRT refined Analysis
  38. GRB 210822A: Swift-BAT refined analysis
  39. GRB 210822A: Fermi-LAT detection
  40. GRB 210820A: Swift/UVOT Detection
  41. GRB 210822A: Enhanced Swift-XRT position
  42. Swift GRB 210822A: Global MASTER-Net observations report
  43. GRB 210822A: KAIT Optical Afterglow Confirmation
  44. GRB 210822A: GECAM detection
  45. GRB 210822A: Swift detection of a burst with an optical afterglow
  46. GRB 210820A: Swift-BAT refined analysis
  47. GRB 210820A: LT optical upper limit
  48. GRB 210820A: LCO Optical Upper Limit
  49. GRB 210820A: RATIR Optical Detections
  50. GRB 210820A: NOT optical upper limit
  51. GRB 210820A: Nanshan/NEXT optical upper limit
  52. GRB 210820A: Swift-XRT refined Analysis
  53. GRB 210820A: Enhanced Swift-XRT position
  54. Swift GRB 210820A: Global MASTER-Net observations report
  55. GRB 210820A: Swift detection of a burst with an optical counterpart
  56. Swift GRB210818.68: Global MASTER-Net observations report
  57. Swift GRB 210818A: Global MASTER-Net observations report
  58. GRB 210818A: Swift-XRT refined Analysis
  59. GRB 210818A: Swift-BAT refined analysis
  60. Konus-Wind detection of GRB 210818A
  61. Swift Trigger 1069242 is Cyg X-1
  62. GRB 210818A: AstroSat CZTI detection
  63. GRB 210818A: AGILE detection
  64. GRB 210818A: Enhanced Swift-XRT position
  65. GRB 210818A: Swift detection of a burst with an optical counterpart
  66. GRB 210712A: Fermi GBM observation
  67. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  68. GRB 210807C: Swift-BAT refined analysis
  69. GRB 210807A: Detection by GRBAlpha
  70. GRB 210807A: Swift-BAT refined analysis
  71. GRB 210802A: Further Swift/XRT observation and afterglow confirmation
  72. GRB 210807C: Swift-XRT refined Analysis
  73. GRB 210807C: Fermi GBM detection
  74. GRB 210807C: Swift/UVOT Upper Limits
  75. GRB 210807A: Swift/UVOT Detection
  76. GRB 210807A: Swift-XRT refined Analysis
  77. GRB 210807C: Enhanced Swift-XRT position
  78. Swift GRB210807.74: Global MASTER-Net observations report
  79. Swift GRB210807.96: Global MASTER-Net observations report
  80. GRB 210807C: Swift detection of a burst
  81. Swift GRB 210807A: Global MASTER-Net observations report
  82. Swift GRB210807.79: Global MASTER-Net observations report
  83. Swift GRB210807.78: Global MASTER-Net observations report
  84. GRB 210807A: Enhanced Swift-XRT position
  85. GRB 210807A: BOOTES-5/JGT optical afterglow detection
  86. GRB 210807A: Swift detection of a burst with an optical counterpart
  87. IPN Triangulation of a bright burst from SGR 1935+2154
  88. GRB 210802A: BOOTES-2/TELMA optical upper limit
  89. GRB 210802A: Swift-XRT afterglow detection
  90. GRB 210802A: Fermi-LAT detection
  91. GRB 210802A: Tiled Swift observations
  92. GRB 210731A: continued GROND observations
  93. GRB 210731A: KAIT Optical Detection
  94. GRB 210731A: Swift-BAT refined analysis
  95. GRB 210731A: MASTER optical afterglow detection
  96. GRB 210731A: Swift-XRT refined Analysis
  97. GRB 210731A: GROND observations
  98. GRB 210731A: Fermi GBM Observation
  99. GRB 210731A: Swift/UVOT Detection of an optical afterglow
  100. Swift GRB210731.62: Global MASTER-Net observations report

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