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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"

19664 results found.

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

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