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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 240225C: AstroSat CZTI detection
  2. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  3. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  4. Transient EPW20240219aa: Mondy optical observations
  5. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  6. GRB 240222A: GECAM detection of a burst
  7. GRB 240222A: Swift-BAT refined analysis
  8. GRB 240222A: Swift-XRT refined Analysis
  9. GRB 240222A: Fermi GBM Observation
  10. GRB 240222A: Swift/UVOT Upper Limits
  11. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  12. Swift GRB 240222A: Global MASTER-Net observations report
  13. Fermi GRB 240222A: Global MASTER-Net observations report
  14. Swift Trigger 1216864 is not an astrophysical event
  15. GRB 240222A: REM optical and NIR early-time observations
  16. GRB 240222A: Swift detection of a burst
  17. GRB 240222A: Fermi GBM Final Real-time Localization
  18. Swift GRB240221.92: Global MASTER-Net observations report
  19. GRB 240218A: MeerLICHT upper limits
  20. GRB 240216A: Glowbug gamma-ray detection
  21. GRB 240215B: Fermi GBM Observation
  22. GRB 240218A: LBT H-band detection
  23. GRB 240218A: Swift-BAT refined analysis
  24. Fermi GRB 240220A: Global MASTER-Net observations report
  25. GRB 240220A: Fermi GBM Final Real-time Localization
  26. GRB 240218A: Swift-XRT refined Analysis
  27. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  28. GRB 240218A: Fermi GBM Detection
  29. GRB 240215A: Fermi GBM Observation
  30. GRB 240216A: GRBAlpha detection
  31. IPN triangulation of GRB 240209A
  32. Fermi trigger No 729914426: Global MASTER-Net observations report
  33. GRB 240218A: Swift detection of a burst
  34. Swift GRB240218.08: Global MASTER-Net observations report
  35. GRB 240215C: Fermi GBM Final Real-time Localization
  36. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  37. Fermi GRB 240216A: Global MASTER-Net observations report
  38. GRB 240216A: Fermi GBM Final Real-time Localization
  39. Fermi trigger No 729719508: Global MASTER-Net observations report
  40. GRB 240215A: Swift/BAT-GUANO localization of a burst
  41. Fermi trigger No 729703985: Global MASTER-Net observations report
  42. Fermi trigger No 729650855: Global MASTER-Net observations report
  43. GRB 240209A: Fermi GBM observation
  44. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  45. Fermi GRB 240213A: Global MASTER-Net observations report
  46. GRB 240213A: Fermi GBM Final Real-time Localization
  47. GRB 240209A: GOTO optical counterpart candidate
  48. Konus-Wind detection of GRB 240205A (short)
  49. GRB 240209A: Fermi GBM Final Localization
  50. Fermi trigger No 729152364: Global MASTER-Net observations report
  51. IPN triangulation of GRB 240205A (short)
  52. GRB 240205A (short): Glowbug gamma-ray detection
  53. Swift Trigger 1213872 is not an astrophysical event
  54. GRB240204A: Swift/UVOT Upper Limits
  55. Fermi trigger No 729012023: Global MASTER-Net observations report
  56. GRB 240205B: Swift-BAT refined analysis
  57. GRB 240207A: Fermi GBM Final Real-time Localization
  58. Konus-Wind detection of GRB 240125A
  59. GRB 240205B: VLT/X-shooter redshift
  60. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  61. GRB 240205B: BOOTES-6 optical afterglow follow-up
  62. GRB 240205B: REM detection of the optical/NIR afterglow
  63. GRB 240205B: Fermi GBM Observation
  64. GRB 240205B: GECAM detection of a long burst
  65. GRB 240204A: Swift-BAT refined analysis
  66. GRB 240205B: Skynet Optical Afterglow Observations
  67. GRB 240205B: BOOTES-7 optical afterglow follow-up
  68. Fermi trigger No 728749569: Global MASTER-Net observations report
  69. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  70. GRB 240205B: Swift detection of a burst
  71. GRB 240205B: Fermi GBM Final Real-time Localization
  72. Swift GRB240205.93: Global MASTER-Net observations report
  73. GRB 240204A: Fermi GBM Observation
  74. GRB 240205A: Fermi GBM Final Real-time Localization
  75. GRB 240204A: Osservatorio Astronomico Nastro Verde upper limit
  76. Fermi Gamma-ray Burst Monitor trigger 728740048/240204491 is not a GRB
  77. Fermi trigger No 728796365: Global MASTER-Net observations report
  78. Fermi Gamma-ray Burst Monitor trigger 728706420/240204102 is not a GRB
  79. Fermi GRB 240204A: Global MASTER-Net observations report
  80. Fermi trigger No 728706420: Global MASTER-Net observations report
  81. GRB 240204A: Swift detection of a burst
  82. GRB 240204A: Fermi GBM Final Real-time Localization
  83. IceCube Alert 240204.38: Global MASTER-Net observations report
  84. Swift Trigger 1212791 is not an astrophysical event.
  85. GRB 230812B: Update on Bad Time Intervals for Fermi GBM data
  86. GRB 240129A: Fermi GBM Observation
  87. IPN triangulation of GRB 240125B (short)
  88. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  89. GRB 240128A: Glowbug gamma-ray detection
  90. GRB 240128A: GRBAlpha detection
  91. GRB 240128A: CALET Gamma-Ray Burst Monitor detection
  92. GRB 240125A: GRBAlpha detection
  93. Fermi GRB 240127A: Global MASTER-Net observations report
  94. GRB 240127A: Fermi GBM Final Real-time Localization
  95. GRB 240125A: CALET Gamma-Ray Burst Monitor detection
  96. Swift Trigger 1211211 and 1211212 are not astrophysical
  97. GRB 240125B: Fermi GBM Final Localization
  98. GRB 240123B: Fermi GBM Observation
  99. GRB 240125A (short): Glowbug gamma-ray detection
  100. GRB 240123B: Swift/BAT-GUANO detection of a long burst

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