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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

21220 results found.

  1. GRB 240225C: Glowbug gamma-ray detection
  2. GRB 240225A (short): Glowbug gamma-ray detection
  3. GRB 240229A: DDOTI Upper Limits on the Afterglow
  4. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  5. Swift BAT Triggers 1218081 and 1218082 are not astrophysical
  6. Fermi GRB 240229A: Global MASTER-Net observations report
  7. IceCube Alert 240229.66: Global MASTER-Net observations report
  8. Konus-Wind detection of GRB 240225B (long)
  9. GRB 240229A: BALROG localization (Fermi Trigger 730908432 / GRB 240229588)
  10. GRB 240229A: Fermi GBM Final Real-time Localization
  11. GRB 240225B: VLT/X-shooter redshift
  12. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  13. GRB 240225B: 3.6m DOT observation
  14. Fermi GRB 240227A: Global MASTER-Net observations report
  15. GRB 240225B: Liverpool Telescope afterglow observations
  16. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  17. Swift Trigger 1217799 is not a GRB
  18. IPN triangulation of GRB 240227A (short)
  19. GRB 240225B: NOT optical observations
  20. Fermi GRB 240226A: Global MASTER-Net observations report
  21. Swift-BAT triggers 1217733 - 1217736 are not astrophysical events
  22. Swift-BAT triggers 1217729-1217732 are not astrophysical
  23. GRB 240227A: Fermi GBM Final Real-time Localization
  24. Fermi Gamma-ray Burst Monitor trigger 730618809/240226236 is not a GRB
  25. GRB 240226B: Fermi GBM Final Real-time Localization
  26. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  27. GRB 240225B: GOTO detection of a candidate optical afterglow
  28. GRB 240226A: Fermi GBM Final Real-time Localization
  29. Transient EPW20240219aa: REM optical/NIR upper limits
  30. GRB 240225C: GRBAlpha detection
  31. Fermi trigger No 730618809: Global MASTER-Net observations report
  32. GRB 240225C: AstroSat CZTI detection
  33. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  34. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  35. GRB 240222A: GRBAlpha detection
  36. Swift-BAT triggers 1217218-1217222 are not astrophysical
  37. Transient EPW20240219aa: Mondy optical observations
  38. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  39. Swift BAT Sub-Threshold Detection of EPW20240219aa
  40. GRB 240222A: GECAM detection of a burst
  41. GRB 240222A: Swift-BAT refined analysis
  42. GRB 240222A: Swift-XRT refined Analysis
  43. Swift-BAT triggers 1216907-1216911 are not astrophysical
  44. GRB 240222A: Fermi GBM Observation
  45. GRB 240222A: Swift/UVOT Upper Limits
  46. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  47. Swift GRB 240222A: Global MASTER-Net observations report
  48. Fermi 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. GRB 240222A: Fermi GBM Final Real-time Localization
  53. Swift-BAT triggers 1216751 and 1216753 are not astrophysical events
  54. Swift-BAT triggers 1216743-1216748 are not astrophysical
  55. Swift GRB240221.92: Global MASTER-Net observations report
  56. GRB 240218A: MeerLICHT upper limits
  57. GRB 240216A: Glowbug gamma-ray detection
  58. GRB 240215B: Fermi GBM Observation
  59. GRB 240218A: LBT H-band detection
  60. GRB 240218A: Swift-BAT refined analysis
  61. Fermi GRB 240220A: Global MASTER-Net observations report
  62. GRB 240220A: Fermi GBM Final Real-time Localization
  63. Konus-Wind detection of GRB 240218A
  64. GRB 240218A: Swift-XRT refined Analysis
  65. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  66. GRB 240218A: Fermi GBM Detection
  67. GRB 240215A: Fermi GBM Observation
  68. GRB 240216A: GRBAlpha detection
  69. GRB 240215B: GRBAlpha detection
  70. IPN triangulation of GRB 240209A
  71. Fermi trigger No 729914426: Global MASTER-Net observations report
  72. GRB 240218A: Swift detection of a burst
  73. Swift GRB240218.08: Global MASTER-Net observations report
  74. GRB 240215C: Fermi GBM Final Real-time Localization
  75. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  76. Fermi GRB 240216A: Global MASTER-Net observations report
  77. Swift Triggers 12156887-1215690 are not astrophysical events.
  78. GRB 240216A: Fermi GBM Final Real-time Localization
  79. Fermi trigger No 729719508: Global MASTER-Net observations report
  80. GRB 240215A: Tiled Swift observations
  81. GRB 240215A: Swift/BAT-GUANO localization of a burst
  82. Fermi trigger No 729703985: Global MASTER-Net observations report
  83. Fermi trigger No 729650855: Global MASTER-Net observations report
  84. GRB 240209A: Fermi GBM observation
  85. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  86. Fermi GRB 240213A: Global MASTER-Net observations report
  87. GRB 240213A: Fermi GBM Final Real-time Localization
  88. GRB 240209A: GOTO optical counterpart candidate
  89. Konus-Wind detection of GRB 240204A
  90. Konus-Wind detection of GRB 240205A (short)
  91. GRB 240209A: Fermi GBM Final Localization
  92. Fermi trigger No 729152364: Global MASTER-Net observations report
  93. IPN triangulation of GRB 240205A (short)
  94. GRB 240205B: PRIME near infrared detection
  95. GRB 240205A (short): Glowbug gamma-ray detection
  96. Swift Trigger 1213872 is not an astrophysical event
  97. GRB240204A: Swift/UVOT Upper Limits
  98. GRB 240205B: AstroSat CZTI detection
  99. Fermi trigger No 729012023: Global MASTER-Net observations report
  100. GRB 240205B: Swift-BAT refined analysis

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