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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"

27284 results found.

  1. Fermi GRB 240317A: Global MASTER-Net observations report
  2. GRB 240317B: Fermi GBM Final Real-time Localization
  3. GRB 240317A: Fermi GBM Final Real-time Localization
  4. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  5. X-ray transient EP240315a: Nanshan/HMT optical upper limit
  6. Fermi trigger No 732299243: Global MASTER-Net observations report
  7. Einstein Probe detected of a fast X-ray transient EP240315a
  8. GRID detection of GRB 240306A
  9. Changes to the Fermi-GBM Triggering Thresholds
  10. GRB 240315A: Fermi GBM Final Real-time Localization
  11. Fermi GRB 240314A: Global MASTER-Net observations report
  12. GRB 240314A: Fermi GBM Final Real-time Localization
  13. GRB 240312A: Glowbug gamma-ray detection
  14. Swift Trigger 1219909 and 1219910 are not a astrophysical
  15. Swift Trigger 1219905 is not a GRB
  16. GRB 240312A: GECAM detection of a long burst
  17. Swift Trigger 1219874 is not astrophysical
  18. GRB 240303C: VZLUSAT-2 detection
  19. Fermi trigger No 731839490: Global MASTER-Net observations report
  20. GRB 240310B: Glowbug gamma-ray detection
  21. Fermi GRB 240310A: Global MASTER-Net observations report
  22. Swift GRB240309.61: Global MASTER-Net observations report
  23. GRB 240310A: Fermi GBM Final Real-time Localization
  24. Swift Trigger 1219325 is not a GRB
  25. GRID detection of GRB 240229A (Updated Report)
  26. GRB 240308A: Fermi GBM Final Localization
  27. Fermi trigger No 731571927: Global MASTER-Net observations report
  28. GRB 240306A: Fermi GBM observation
  29. IceCube Alert 240307.32: Global MASTER-Net observations report
  30. Fermi GRB 240306A: Global MASTER-Net observations report
  31. Fermi GRB 240305A: Global MASTER-Net observations report
  32. GRB 240306A: Swift/BAT-GUANO detection of a burst
  33. GRB 240305A: Fermi GBM observation
  34. GRB 240306A: Fermi GBM Final Real-time Localization
  35. Swift GRB240305.18: Global MASTER-Net observations report
  36. Swift GRB240305.16: Global MASTER-Net observations report
  37. Fermi GRB 240305C: Global MASTER-Net observations report
  38. GRB 240305C: Fermi GBM Final Real-time Localization
  39. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  40. GRB 231028C: Glowbug gamma-ray confirmation of a prior burst
  41. GRB 240218A: Chandra Detection and Jet Break Confirmation
  42. GRB 240305B: Fermi GBM Final Localization
  43. Fermi trigger No 731303574: Global MASTER-Net observations report
  44. Konus-Wind detection of GRB 240227A (short/hard)
  45. IPN triangulation of GRB 240229A
  46. GRB 240305A: Fermi GBM Final Real-time Localization
  47. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  48. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  49. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  50. IPN triangulation of GRB 240303B
  51. Swift J151857.0-572147: Swift-BAT refined analysis
  52. GRB 240303B: Fermi GBM Detection
  53. Swift detection of Swift J151857.0-572147
  54. GRB 240303B: CALET Gamma-Ray Burst Monitor detection
  55. Fermi trigger No 731161136: Global MASTER-Net observations report
  56. GRB 240303C: BALROG localization (Fermi Trigger 731189113 / GRB 240303837)
  57. Swift GRB 240303A: Global MASTER-Net observations report
  58. Swift J151857.0-572147: Confirmation of a new galactic transient
  59. GRB 240303B: BALROG localization (Fermi Trigger 731161136 / GRB 240303513)
  60. GRB 240303B: Fermi GBM Final Localization
  61. GRB 240303A: Swift detection of a burst
  62. GRB 240225C: Glowbug gamma-ray detection
  63. GRB 240225A (short): Glowbug gamma-ray detection
  64. GRB 240229A: DDOTI Upper Limits on the Afterglow
  65. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  66. Fermi GRB 240229A: Global MASTER-Net observations report
  67. IceCube Alert 240229.66: Global MASTER-Net observations report
  68. Konus-Wind detection of GRB 240225B (long)
  69. GRB 240229A: BALROG localization (Fermi Trigger 730908432 / GRB 240229588)
  70. GRB 240229A: Fermi GBM Final Real-time Localization
  71. GRB 240225B: VLT/X-shooter redshift
  72. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  73. GRB 240225B: 3.6m DOT observation
  74. Fermi GRB 240227A: Global MASTER-Net observations report
  75. GRB 240225B: Liverpool Telescope afterglow observations
  76. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  77. Swift Trigger 1217799 is not a GRB
  78. IPN triangulation of GRB 240227A (short)
  79. GRB 240225B: NOT optical observations
  80. Fermi GRB 240226A: Global MASTER-Net observations report
  81. GRB 240227A: Fermi GBM Final Real-time Localization
  82. Fermi Gamma-ray Burst Monitor trigger 730618809/240226236 is not a GRB
  83. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  84. GRB 240226B: Fermi GBM Final Real-time Localization
  85. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  86. GRB 240225B: GOTO detection of a candidate optical afterglow
  87. GRB 240226A: Fermi GBM Final Real-time Localization
  88. Transient EPW20240219aa: REM optical/NIR upper limits
  89. GRB 240225C: GRBAlpha detection
  90. Fermi trigger No 730618809: Global MASTER-Net observations report
  91. GRB 240225C: AstroSat CZTI detection
  92. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  93. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  94. Transient EPW20240219aa: Mondy optical observations
  95. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  96. GRB 240222A: GECAM detection of a burst
  97. GRB 240222A: Swift-BAT refined analysis
  98. GRB 240222A: Swift-XRT refined Analysis
  99. GRB 240222A: Fermi GBM Observation
  100. GRB 240222A: Swift/UVOT Upper Limits

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