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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"

27294 results found.

  1. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  2. GRB 240320A: Fermi GBM Final Real-time Localization
  3. Fermi Gamma-ray Burst Monitor trigger 732299243/240316686 is not a GRB
  4. X-ray transient EP240315a: GTC/OSIRIS spectroscopic redshift confirmation
  5. GRB 240317B: Fermi GBM Observation
  6. X-ray transient EP240315a: EP-FXT detection of the X-ray afterglow
  7. Fermi GRB 240318A: Global MASTER-Net observations report
  8. GRB 240318A: Fermi GBM Final Real-time Localization
  9. GRB 240317B: Swift/BAT-GUANO arcminute localization of a burst
  10. Fermi GRB 240317B: Global MASTER-Net observations report
  11. Fermi GRB 240317A: Global MASTER-Net observations report
  12. GRB 240317B: Fermi GBM Final Real-time Localization
  13. GRB 240317A: Fermi GBM Final Real-time Localization
  14. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  15. X-ray transient EP240315a: Nanshan/HMT optical upper limit
  16. Fermi trigger No 732299243: Global MASTER-Net observations report
  17. Einstein Probe detected of a fast X-ray transient EP240315a
  18. GRID detection of GRB 240306A
  19. Changes to the Fermi-GBM Triggering Thresholds
  20. GRB 240315A: Fermi GBM Final Real-time Localization
  21. Fermi GRB 240314A: Global MASTER-Net observations report
  22. GRB 240314A: Fermi GBM Final Real-time Localization
  23. GRB 240312A: Glowbug gamma-ray detection
  24. Swift Trigger 1219909 and 1219910 are not a astrophysical
  25. Swift Trigger 1219905 is not a GRB
  26. GRB 240312A: GECAM detection of a long burst
  27. Swift Trigger 1219874 is not astrophysical
  28. GRB 240303C: VZLUSAT-2 detection
  29. Fermi trigger No 731839490: Global MASTER-Net observations report
  30. GRB 240310B: Glowbug gamma-ray detection
  31. Fermi GRB 240310A: Global MASTER-Net observations report
  32. Swift GRB240309.61: Global MASTER-Net observations report
  33. GRB 240310A: Fermi GBM Final Real-time Localization
  34. Swift Trigger 1219325 is not a GRB
  35. GRID detection of GRB 240229A (Updated Report)
  36. GRB 240308A: Fermi GBM Final Localization
  37. Fermi trigger No 731571927: Global MASTER-Net observations report
  38. GRB 240306A: Fermi GBM observation
  39. IceCube Alert 240307.32: Global MASTER-Net observations report
  40. Fermi GRB 240306A: Global MASTER-Net observations report
  41. Fermi GRB 240305A: Global MASTER-Net observations report
  42. GRB 240306A: Swift/BAT-GUANO detection of a burst
  43. GRB 240305A: Fermi GBM observation
  44. GRB 240306A: Fermi GBM Final Real-time Localization
  45. Swift GRB240305.18: Global MASTER-Net observations report
  46. Swift GRB240305.16: Global MASTER-Net observations report
  47. Fermi GRB 240305C: Global MASTER-Net observations report
  48. GRB 240305C: Fermi GBM Final Real-time Localization
  49. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  50. GRB 231028C: Glowbug gamma-ray confirmation of a prior burst
  51. GRB 240218A: Chandra Detection and Jet Break Confirmation
  52. GRB 240305B: Fermi GBM Final Localization
  53. Fermi trigger No 731303574: Global MASTER-Net observations report
  54. Konus-Wind detection of GRB 240227A (short/hard)
  55. IPN triangulation of GRB 240229A
  56. GRB 240305A: Fermi GBM Final Real-time Localization
  57. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  58. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  59. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  60. IPN triangulation of GRB 240303B
  61. Swift J151857.0-572147: Swift-BAT refined analysis
  62. GRB 240303B: Fermi GBM Detection
  63. Swift detection of Swift J151857.0-572147
  64. GRB 240303B: CALET Gamma-Ray Burst Monitor detection
  65. Fermi trigger No 731161136: Global MASTER-Net observations report
  66. GRB 240303C: BALROG localization (Fermi Trigger 731189113 / GRB 240303837)
  67. Swift GRB 240303A: Global MASTER-Net observations report
  68. Swift J151857.0-572147: Confirmation of a new galactic transient
  69. GRB 240303B: BALROG localization (Fermi Trigger 731161136 / GRB 240303513)
  70. GRB 240303B: Fermi GBM Final Localization
  71. GRB 240303A: Swift detection of a burst
  72. GRB 240225C: Glowbug gamma-ray detection
  73. GRB 240225A (short): Glowbug gamma-ray detection
  74. GRB 240229A: DDOTI Upper Limits on the Afterglow
  75. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  76. Fermi GRB 240229A: Global MASTER-Net observations report
  77. IceCube Alert 240229.66: Global MASTER-Net observations report
  78. Konus-Wind detection of GRB 240225B (long)
  79. GRB 240229A: BALROG localization (Fermi Trigger 730908432 / GRB 240229588)
  80. GRB 240229A: Fermi GBM Final Real-time Localization
  81. GRB 240225B: VLT/X-shooter redshift
  82. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  83. GRB 240225B: 3.6m DOT observation
  84. Fermi GRB 240227A: Global MASTER-Net observations report
  85. GRB 240225B: Liverpool Telescope afterglow observations
  86. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  87. Swift Trigger 1217799 is not a GRB
  88. IPN triangulation of GRB 240227A (short)
  89. GRB 240225B: NOT optical observations
  90. Fermi GRB 240226A: Global MASTER-Net observations report
  91. GRB 240227A: Fermi GBM Final Real-time Localization
  92. Fermi Gamma-ray Burst Monitor trigger 730618809/240226236 is not a GRB
  93. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  94. GRB 240226B: Fermi GBM Final Real-time Localization
  95. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  96. GRB 240225B: GOTO detection of a candidate optical afterglow
  97. GRB 240226A: Fermi GBM Final Real-time Localization
  98. Transient EPW20240219aa: REM optical/NIR upper limits
  99. GRB 240225C: GRBAlpha detection
  100. Fermi trigger No 730618809: Global MASTER-Net observations report

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