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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"

19663 results found.

  1. GRB 221009A: Swift detected transient may be GRB
  2. Swift GRB221009.59: Global MASTER-Net OT detection
  3. GRB 221008A: Swift-XRT observations
  4. Swift J1913.1+1946 a new bright hard X-ray and optical transient
  5. GRB 221008A: Tiled Swift observations
  6. GRB 221006A: Swift-XRT observations
  7. GRB 221006A: Tiled Swift observations
  8. GRB 220930A: MITSuME Akeno optical upper limits
  9. GRB 220930A: AbAO Optical Upper Limit
  10. Konus-Wind detection of GRB 220930A
  11. GRB 220930A: AstroSat CZTI detection
  12. GRB 220930A: Swift-BAT refined analysis
  13. GRB 220930A: Swift-XRT refined Analysis
  14. GRB 220930A: LCOGT Optical Upper Limits
  15. GRB 220930A: Swift/UVOT Upper Limits
  16. GRB 220930A: Enhanced Swift-XRT position
  17. Swift GRB 220930A: Global MASTER-Net observations report
  18. GRB 220930A: BOOTES-5/JGT early optical upper limit
  19. GRB 220930A: Prompt enhanced Swift-XRT position
  20. GRB 220930A: COATLI Upper Limits
  21. GRB 220930A: Swift detection of a burst
  22. IPN triangulation of GRB 220927A (long)
  23. GRB 220924A: Fermi GBM detection
  24. Swift Trigger 1125354 (GRB 220926A) is not a GRB
  25. Swift GRB220926.34: Global MASTER-Net observations report
  26. Swift GRB 220926A: Global MASTER-Net observations report
  27. GRB 220926A: Swift detection of a burst
  28. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
  29. Swift GRB220923.47: Global MASTER-Net observations report
  30. GRB 220921A: MeerLICHT afterglow observations
  31. GRB 220921A: Swift-XRT Observations
  32. GRB 220921A: Fermi-LAT detection
  33. GRB 220921A: Tiled Swift observations
  34. GRB 220909A: Fermi GBM observation
  35. GRB 220909A: Swift-XRT observations
  36. IPN triangulation of GRB 220905A
  37. GRB 220909A: Swift ToO observations
  38. GRB 220909A: Swift/BAT-GUANO candidate arcminute localization
  39. GRB 220907A: Swift-BAT refined analysis
  40. GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart
  41. IPN triangulation of GRB 220903A (long)
  42. GRB 220907A: Fermi GBM observation
  43. GRB 220907A: Nanshan/NEXT optical upper limits
  44. GRB 220907A: Swift/UVOT Upper Limits
  45. GRB 220907A: Swift-XRT refined Analysis
  46. GRB 220831A: ATCA 5/9 GHz radio observations
  47. GRB 220907A: Swift-XRT position
  48. GRB 220907A: Swift detection of a burst
  49. Swift GRB220907.59: Global MASTER-Net observations report
  50. GRB 220831A: Swift-UVOT Upper Limits
  51. GRB 220831A: DECam detection of a possible optical counterpart
  52. GRB 220831A, VLT/HAWK-I near-infrared observations
  53. GRB 220831A: Fermi GBM observation
  54. GRB 220831A: Swift-XRT observations
  55. GRB 220831A: Swift ToO observations
  56. GRB 220831A: Swift/BAT-GUANO localization of a short burst
  57. Konus-Wind detection of GRB 220826A
  58. GRB 220826A: Swift-BAT refined analysis
  59. GRB 220826A: Fermi GBM observation
  60. GRB 220826A: Swift-XRT refined Analysis
  61. GRB 220825A: Fermi GBM observation
  62. GRB 220826A: Lesedi optical afterglow detection
  63. GRB 220826A: Swift/UVOT Detection
  64. Swift GRB 220826A: Global MASTER-Net observations report
  65. GRB 220826A: Enhanced Swift-XRT position
  66. GRB 220826A: Swift detection of a burst with an optical counterpart
  67. GRB 220825A: Swift/BAT-GUANO detection
  68. GRB 220823A: Fermi GBM detection
  69. GRB 220823A: Swift/BAT-GUANO detection of a short burst
  70. Konus-Wind detection of GRB 220813A
  71. GRB 220813A: VLT optical observations and possible host galaxy
  72. GRB 220813A: Swift/UVOT Detection
  73. GRB 220810A: Further Swift-XRT observations
  74. GRB 220813A: Swift-XRT refined Analysis
  75. Swift GRB 220813A: Global MASTER-Net observations report
  76. GRB 220813A: Enhanced Swift-XRT position
  77. GRB 220813A: Swift detection of a burst with an optical counterpart
  78. GRB 220810A: Swift-XRT observations
  79. GRB 220810A: Swift ToO observations
  80. GRB 220806A: Swift-BAT refined analysis
  81. GRB 220806A: Swift detection of a burst
  82. Swift GRB220806.76: Global MASTER-Net observations report
  83. Konus-Wind detection of GRB 220730A (short)
  84. GRB 220730A: Swift-BAT refined analysis
  85. GRB 220730A: Fermi GBM detection
  86. GRB 220730A: Swift-XRT afterglow detection
  87. GRB 220730A: Swift/UVOT Upper Limits
  88. GRB 220730A: Swift-XRT observations
  89. Swift GRB 220730A: Global MASTER-Net observations report
  90. GRB 220730A: Swift detection of a short hard burst
  91. GRB 220711B: CALET Gamma-Ray Burst Monitor detection
  92. GRB 220715B: Swift-BAT refined analysis
  93. GRB220714B: UVOT detections
  94. GRB 220715B: Fermi GBM detection
  95. GRB 220715B: Swift-XRT refined Analysis
  96. GRB 220715B: Swift/UVOT Upper Limits
  97. GRB 220715B: Enhanced Swift-XRT position
  98. GRB 220715B: BOOTES-network optical upper limits
  99. Swift GRB 220715B: Global MASTER-Net observations report
  100. GRB 220715B: Prompt enhanced Swift-XRT position

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