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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. IPN triangulation of a bright burst from SGR 1935+2154
  2. GRB 210826A: further Swift-XRT observations
  3. Swift detection of a burst from SGR Swift J1555.2-5402
  4. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  5. GRB 210905A: Swift/UVOT Upper Limits
  6. GRB 210905A: AstroSat CZTI detection
  7. GRB 210905A, GROND observations
  8. Konus-Wind detection of GRB 210905A
  9. Fermi GBM Sub-Threshold Detection of GRB 210905A
  10. GRB 210905A: Swift-XRT refined Analysis
  11. GRB 210905A: DECam Detection
  12. GRB 210905A: Continued LCO Optical Observations
  13. GRB 210905A: LCO Optical Detection
  14. GRB 210905A: Enhanced Swift-XRT position
  15. GRB 210901A: Swift/UVOT Upper Limits
  16. Swift GRB 210905A: Global MASTER-Net observations report
  17. GRB 210905A: Swift detection of a burst
  18. Swift GRB210903.59: Global MASTER-Net observations report
  19. Swift GRB210903.58: Global MASTER-Net observations report
  20. Swift GRB210903.58: Global MASTER-Net observations report
  21. GRB 210901A: GROND observations
  22. Fermi GBM observation of a burst from SGR J1555.2-5402
  23. GRB 210901A: Swift-XRT refined Analysis
  24. GRB 210901A: Swift-BAT refined analysis
  25. GRB 210901A: Enhanced Swift-XRT position
  26. GRB 210901A: LCO Optical Upper Limit
  27. Swift GRB 210901A: Global MASTER-Net observations report
  28. GRB 210901A: Swift detection of a burst
  29. GRB 210827A: further Swift-XRT observations
  30. GRB 210822A: CALET Gamma-Ray Burst Monitor detection
  31. GRB 210827A: Swift/UVOT Upper Limits
  32. GRB 210827A: BOOTES-5/JGT optical upper limit
  33. GRB 210827A: Fermi GBM Observation
  34. GRB 210827A: Swift-XRT observations
  35. GRB 210827A: Swift ToO observations
  36. GRB 210827A: Swift/BAT-GUANO detection and arcminute localization
  37. GRB 210820A: CAHA 2.2m Optical Detection
  38. GRB 210824A: Swift/UVOT Upper Limits
  39. GRB 210826A: Swift/UVOT Upper Limits
  40. GRB 210826A: Swift-XRT observations
  41. GRB 210822A: CAHA 2.2m observations
  42. GRB 210824A: Swift-BAT refined analysis
  43. GRB 210826A: Fermi-LAT detection
  44. GRB 210826A: Tiled Swift observations
  45. GRB 210824A: MITSuME Akeno optical upper limits
  46. Swift GRB210825.29: Global MASTER-Net observations report
  47. GRB 210822A: VLA detection
  48. Swift detection of an outburst from SGR Swift J1555.2-5402
  49. GRB 210822A: Swift/UVOT Detection
  50. Swift GRB 210824A: Global MASTER-Net observations report
  51. GRB 210824A: BOOTES-5/JGT optical upper limit
  52. GRB 210824A: Fermi GBM Observation
  53. GRB 210824A: Nanshan/NEXT optical upper limit
  54. GRB 210824A: Swift-XRT refined Analysis
  55. GRB 210822A: GROND observations
  56. GRB 210824A: Enhanced Swift-XRT position
  57. GRB 210824A: Swift detection of a burst
  58. GRB 210822A: Detection by GRBAlpha
  59. GRB 210822A: GECAM refined analysis
  60. GRB 210820A: GROND observations
  61. Konus-Wind detection of GRB 210822A
  62. GRB 210822A: AstroSat CZTI detection
  63. GRB 210822A: Swift-XRT refined Analysis
  64. GRB 210822A: Swift-BAT refined analysis
  65. GRB 210820A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  66. GRB 210822A: Fermi-LAT detection
  67. GRB 210820A: Swift/UVOT Detection
  68. GRB 210822A: Enhanced Swift-XRT position
  69. Swift GRB 210822A: Global MASTER-Net observations report
  70. GRB 210822A: KAIT Optical Afterglow Confirmation
  71. GRB 210822A: GECAM detection
  72. GRB 210822A: Swift detection of a burst with an optical afterglow
  73. GRB 210820A: Swift-BAT refined analysis
  74. GRB 210820A: LT optical upper limit
  75. GRB 210820A: LCO Optical Upper Limit
  76. GRB 210820A: RATIR Optical Detections
  77. GRB 210820A: NOT optical upper limit
  78. GRB 210820A: Nanshan/NEXT optical upper limit
  79. GRB 210820A: Swift-XRT refined Analysis
  80. GRB 210820A: Enhanced Swift-XRT position
  81. Swift GRB 210820A: Global MASTER-Net observations report
  82. GRB 210820A: Swift detection of a burst with an optical counterpart
  83. Swift GRB210818.68: Global MASTER-Net observations report
  84. Swift GRB 210818A: Global MASTER-Net observations report
  85. GRB 210818A: Swift-XRT refined Analysis
  86. GRB 210818A: Swift-BAT refined analysis
  87. Konus-Wind detection of GRB 210818A
  88. Swift Trigger 1069242 is Cyg X-1
  89. GRB 210818A: AstroSat CZTI detection
  90. GRB 210818A: AGILE detection
  91. GRB 210818A: Enhanced Swift-XRT position
  92. GRB 210818A: Swift detection of a burst with an optical counterpart
  93. GRB 210712A: Fermi GBM observation
  94. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  95. GRB 210730A: Tautenburg observations
  96. GRB 210807C: Swift-BAT refined analysis
  97. GRB 210807A: Detection by GRBAlpha
  98. GRB 210807A: Swift-BAT refined analysis
  99. GRB 210802A: Further Swift/XRT observation and afterglow confirmation
  100. GRB 210807C: Swift-XRT refined Analysis

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