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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. Swift Trigger 1219325 is not a GRB
  2. GRB 240306A: Fermi GBM observation
  3. Konus-Wind detection of GRB 231118A
  4. GRB 240306A: AstroSat CZTI detection
  5. GRB 240306A: Swift/BAT-GUANO detection of a burst
  6. GRB 240305A: Fermi GBM observation
  7. Swift GRB240305.18: Global MASTER-Net observations report
  8. Swift GRB240305.16: Global MASTER-Net observations report
  9. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  10. GRB 240218A: Chandra Detection and Jet Break Confirmation
  11. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  12. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  13. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  14. Swift J151857.0-572147: Swift-BAT refined analysis
  15. GRB 240225B: Swift-XRT afterglow detection
  16. Swift detection of Swift J151857.0-572147
  17. Swift GRB 240303A: Global MASTER-Net observations report
  18. Swift J151857.0-572147: Confirmation of a new galactic transient
  19. GRB 240215A: Swift-XRT afterglow detection
  20. GRB 240303A: Swift detection of a burst
  21. GRB 240225A (short): Glowbug gamma-ray detection
  22. Swift BAT Triggers 1218081 and 1218082 are not astrophysical
  23. GRB 240225B: Swift ToO observations
  24. GRB 240225B: 3.6m DOT observation
  25. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  26. Swift Trigger 1217799 is not a GRB
  27. GRB 240218A: CMO SAI NIR upper limit
  28. Swift-BAT triggers 1217733 - 1217736 are not astrophysical events
  29. Swift-BAT triggers 1217729-1217732 are not astrophysical
  30. GRB 240225B: Nanshan/HMT optical afterglow detection
  31. GRB 240225B: Swift-XRT observations
  32. GRB 240225B: GOTO detection of a candidate optical afterglow
  33. GRB 240222A: ATCA radio observations
  34. GRB 240225B: Tiled Swift observations
  35. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  36. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  37. GRB 240222A: GRBAlpha detection
  38. Swift-BAT triggers 1217218-1217222 are not astrophysical
  39. Transient EPW20240219aa: Mondy optical observations
  40. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  41. Swift BAT Sub-Threshold Detection of EPW20240219aa
  42. GRB 240222A: GECAM detection of a burst
  43. GRB 240222A: Swift-BAT refined analysis
  44. GRB 240222A: Swift-XRT refined Analysis
  45. Swift-BAT triggers 1216907-1216911 are not astrophysical
  46. GRB 240222A: Fermi GBM Observation
  47. GRB 240222A: Swift/UVOT Upper Limits
  48. Swift GRB 240222A: Global MASTER-Net observations report
  49. Swift Trigger 1216864 is not an astrophysical event
  50. GRB 240222A: REM optical and NIR early-time observations
  51. GRB 240222A: Swift detection of a burst
  52. Swift-BAT triggers 1216751 and 1216753 are not astrophysical events
  53. Swift-BAT triggers 1216743-1216748 are not astrophysical
  54. Swift GRB240221.92: Global MASTER-Net observations report
  55. GRB 240218A: MeerLICHT upper limits
  56. GRB 240215B: Fermi GBM Observation
  57. GRB 240218A: LBT H-band detection
  58. GRB 240218A: Swift-BAT refined analysis
  59. Konus-Wind detection of GRB 240218A
  60. GRB 240218A: Swift-XRT refined Analysis
  61. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  62. GRB 240218A: Fermi GBM Detection
  63. GRB 240215A: Fermi GBM Observation
  64. GRB 240215B: GRBAlpha detection
  65. IPN triangulation of GRB 240209A
  66. GRB 240218A: Enhanced Swift-XRT position
  67. GRB 240218A: REM detection of a NIR afterglow candidate
  68. GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
  69. GRB240218A: VLT/X-shooter upper limits
  70. GRB 240218A: Swift detection of a burst
  71. Swift GRB240218.08: Global MASTER-Net observations report
  72. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  73. Swift Triggers 12156887-1215690 are not astrophysical events.
  74. GRB 240215A: Tiled Swift observations
  75. GRB 240215A: Swift/BAT-GUANO localization of a burst
  76. GRB 240128A: Further Swift-XRT observations
  77. GRB 240214A: Tiled Swift observations
  78. GRB 240214A/1H 0451-560: MAXI/GSC detection
  79. Konus-Wind detection of GRB 240204A
  80. IPN triangulation of GRB 240205A (short)
  81. GRB 240205B: PRIME near infrared detection
  82. Swift Trigger 1213872 is not an astrophysical event
  83. GRB240204A: Swift/UVOT Upper Limits
  84. GRB 240205B: AstroSat CZTI detection
  85. GRB 240205B: Swift-BAT refined analysis
  86. Konus-Wind detection of GRB 240205B (long / very soft)
  87. GRB 240205B: VLT/X-shooter redshift
  88. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  89. GRB 240205B: BOOTES-6 optical afterglow follow-up
  90. GRB 240205B: ATCA detection of radio counterpart
  91. GRB 240205B: REM detection of the optical/NIR afterglow
  92. GRB 240205B: Fermi GBM Observation
  93. GRB 240204A: AstroSat CZTI detection
  94. GRB 240205B: GECAM detection of a long burst
  95. GRB 240204A: Swift-BAT refined analysis
  96. GRB 240205B: Skynet Optical Afterglow Observations
  97. GRB 240205B: BOOTES-7 optical afterglow follow-up
  98. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  99. GRB 240205B: Swift detection of a burst
  100. Swift GRB240205.93: Global MASTER-Net observations report

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