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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 240305A: Fermi GBM observation
  2. Swift GRB240305.18: Global MASTER-Net observations report
  3. Swift GRB240305.16: Global MASTER-Net observations report
  4. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  5. GRB 240218A: Chandra Detection and Jet Break Confirmation
  6. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  7. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  8. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  9. Swift J151857.0-572147: Swift-BAT refined analysis
  10. GRB 240225B: Swift-XRT afterglow detection
  11. Swift detection of Swift J151857.0-572147
  12. Swift GRB 240303A: Global MASTER-Net observations report
  13. Swift J151857.0-572147: Confirmation of a new galactic transient
  14. GRB 240215A: Swift-XRT afterglow detection
  15. GRB 240303A: Swift detection of a burst
  16. GRB 240225A (short): Glowbug gamma-ray detection
  17. Swift BAT Triggers 1218081 and 1218082 are not astrophysical
  18. GRB 240225B: Swift ToO observations
  19. GRB 240225B: 3.6m DOT observation
  20. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  21. Swift Trigger 1217799 is not a GRB
  22. Swift-BAT triggers 1217733 - 1217736 are not astrophysical events
  23. Swift-BAT triggers 1217729-1217732 are not astrophysical
  24. GRB 240225B: Nanshan/HMT optical afterglow detection
  25. GRB 240225B: Swift-XRT observations
  26. GRB 240225B: GOTO detection of a candidate optical afterglow
  27. GRB 240225B: Tiled Swift observations
  28. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  29. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  30. GRB 240222A: GRBAlpha detection
  31. Swift-BAT triggers 1217218-1217222 are not astrophysical
  32. Transient EPW20240219aa: Mondy optical observations
  33. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  34. Swift BAT Sub-Threshold Detection of EPW20240219aa
  35. GRB 240222A: GECAM detection of a burst
  36. GRB 240222A: Swift-BAT refined analysis
  37. GRB 240222A: Swift-XRT refined Analysis
  38. Swift-BAT triggers 1216907-1216911 are not astrophysical
  39. GRB 240222A: Fermi GBM Observation
  40. GRB 240222A: Swift/UVOT Upper Limits
  41. Swift GRB 240222A: Global MASTER-Net observations report
  42. Swift Trigger 1216864 is not an astrophysical event
  43. GRB 240222A: Swift detection of a burst
  44. Swift-BAT triggers 1216751 and 1216753 are not astrophysical events
  45. Swift-BAT triggers 1216743-1216748 are not astrophysical
  46. Swift GRB240221.92: Global MASTER-Net observations report
  47. GRB 240218A: MeerLICHT upper limits
  48. GRB 240215B: Fermi GBM Observation
  49. GRB 240218A: LBT H-band detection
  50. GRB 240218A: Swift-BAT refined analysis
  51. Konus-Wind detection of GRB 240218A
  52. GRB 240218A: Swift-XRT refined Analysis
  53. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  54. GRB 240218A: Fermi GBM Detection
  55. GRB 240215A: Fermi GBM Observation
  56. GRB 240215B: GRBAlpha detection
  57. IPN triangulation of GRB 240209A
  58. GRB 240218A: Enhanced Swift-XRT position
  59. GRB 240218A: REM detection of a NIR afterglow candidate
  60. GRB 240218A: Swift detection of a burst
  61. Swift GRB240218.08: Global MASTER-Net observations report
  62. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  63. Swift Triggers 12156887-1215690 are not astrophysical events.
  64. GRB 240215A: Tiled Swift observations
  65. GRB 240215A: Swift/BAT-GUANO localization of a burst
  66. GRB 240128A: Further Swift-XRT observations
  67. GRB 240214A: Tiled Swift observations
  68. GRB 240214A/1H 0451-560: MAXI/GSC detection
  69. Konus-Wind detection of GRB 240204A
  70. IPN triangulation of GRB 240205A (short)
  71. GRB 240205B: PRIME near infrared detection
  72. Swift Trigger 1213872 is not an astrophysical event
  73. GRB240204A: Swift/UVOT Upper Limits
  74. GRB 240205B: AstroSat CZTI detection
  75. GRB 240205B: Swift-BAT refined analysis
  76. Konus-Wind detection of GRB 240205B (long / very soft)
  77. GRB 240205B: VLT/X-shooter redshift
  78. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  79. GRB 240205B: BOOTES-6 optical afterglow follow-up
  80. GRB 240205B: ATCA detection of radio counterpart
  81. GRB 240205B: REM detection of the optical/NIR afterglow
  82. GRB 240205B: Fermi GBM Observation
  83. GRB 240204A: AstroSat CZTI detection
  84. GRB 240205B: GECAM detection of a long burst
  85. GRB 240204A: Swift-BAT refined analysis
  86. GRB 240205B: Skynet Optical Afterglow Observations
  87. GRB 240205B: BOOTES-7 optical afterglow follow-up
  88. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  89. GRB 240205B: Swift detection of a burst
  90. Swift GRB240205.93: Global MASTER-Net observations report
  91. GRB 240204A: Fermi GBM Observation
  92. GRB 240204A: Osservatorio Astronomico Nastro Verde upper limit
  93. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  94. GRB 240204A: Montarrenti Observatory optical observations
  95. GRB 240204A: Enhanced Swift-XRT position
  96. GRB 240204A: Mondy optical afterglow candidate
  97. GRB 240204A: Swift detection of a burst
  98. Swift Trigger 1212791 is not an astrophysical event.
  99. Swift-BAT triggers 1212787, 1212789 are not astrophysical.
  100. IPN triangulation of GRB 240124B

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