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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').
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"

11112 results found.

  1. Fermi GRB 240502A: Global MASTER-Net observations report
  2. GRB 240430A: GRBAlpha detection
  3. GRB 240502B: Fermi GBM Final Real-time Localization
  4. GRB 240502A: Fermi GBM Final Real-time Localization
  5. Fermi GRB 240501A: Global MASTER-Net observations report
  6. Fermi trigger No 736197684: Global MASTER-Net observations report
  7. GRB 240425A: VZLUSAT-2 detection
  8. GRB240430A: Fermi GBM Final Localization
  9. GRB 240501A: Fermi GBM Final Real-time Localization
  10. GRB 240407A: VZLUSAT-2 detection
  11. GRB 240425A: GRBAlpha detection
  12. Fermi-LAT gamma-ray observations of IceCube-240424A
  13. GRB 240429A: Fermi GBM Final Real-time Localization
  14. Fermi GRB 240428A: Global MASTER-Net observations report
  15. GRB 240428A: Fermi GBM Final Real-time Localization
  16. GRB 240425A: Fermi GBM Final Real-time Localization
  17. Fermi trigger No 735697285: Global MASTER-Net observations report
  18. GRB 240422A: Glowbug gamma-ray detection
  19. IceCube-240424A - IceCube observation of a high-energy neutrino candidate track-like event
  20. GRB 240421B: GRBAlpha detection
  21. LIGO/Virgo/KAGRA S240422ed: Upper limits from Fermi-GBM Observations
  22. Fermi trigger No 735470374: Global MASTER-Net observations report
  23. GRB 240421A: Glowbug gamma-ray detection
  24. GRB 240414A: radio detection with the VLA
  25. Fermi-LAT gamma-ray observations of IceCube-240419A
  26. Fermi GRB 240422A: Global MASTER-Net observations report
  27. GRB 240421B: AstroSat CZTI detection
  28. GRB 240422A: Fermi GBM Final Real-time Localization
  29. Fermi GRB 240421B: Global MASTER-Net observations report
  30. GRB 240421B: Fermi GBM Observation
  31. Fermi GRB 240421A: Global MASTER-Net observations report
  32. GRB 240421A: Fermi GBM Final Real-time Localization
  33. Fermi trigger No 735280430: Global MASTER-Net observations report
  34. IceCube-240419A - IceCube observation of a high-energy neutrino candidate track-like event
  35. IceCube-240419A - IceCube observation of a high-energy neutrino candidate track-like event
  36. Fermi trigger No 735089036: Global MASTER-Net observations report
  37. GRB 240411A: GOTO early optical upper limits
  38. Fermi GRB 240417A: Global MASTER-Net observations report
  39. Improved IPN triangulation of GRB 240411A
  40. GRB 240417A: Fermi GBM Final Real-time Localization
  41. GRB 240415A: Glowbug gamma-ray detection
  42. GRB 240414A: Glowbug gamma-ray detection
  43. GRB 240411A: Glowbug gamma-ray detection
  44. GRB 240415A: Fermi GBM Observation
  45. GRB 240415A: Earliest optical followup with the Kinder observations
  46. GRB 240415A: OHP/T193 optical observations
  47. GRB 240415A: optical afterglow detection from the INAF Asiago Observatory
  48. GRB 240415A: SAO RAS optical observations
  49. GRB 240414A: Fermi GBM Observation
  50. Fermi GRB 240415A: Global MASTER-Net observations report
  51. GRB 240415A: Mondy optical transient detection
  52. GRB 240414B: Fermi GBM Final Real-time Localization
  53. GRB 240415A: Swift detection of a burst
  54. GRB 240415A: Fermi GBM Final Real-time Localization
  55. Fermi trigger No 734754044: Global MASTER-Net observations report
  56. IPN triangulation of GRB 240411A
  57. Fermi-LAT gamma-ray observations of IceCube-240412A
  58. IceCube-240412A - IceCube observation of a high-energy neutrino candidate track-like event
  59. GRB 240411A: GRBAlpha detection
  60. GRB 240405A: Glowbug gamma-ray detection
  61. GRB 240411A: Fermi GBM Final Real-time Localization
  62. GRB 240405A: GRBAlpha detection
  63. Fermi GRB 240408A: Global MASTER-Net observations report
  64. GRB 240408A: Fermi GBM Final Real-time Localization
  65. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  66. Fermi GRB 240407A: Global MASTER-Net observations report
  67. GRB 240407A: Fermi GBM Final Real-time Localization
  68. Fermi-LAT gamma-ray observations of IceCube-240327B
  69. Fermi-LAT gamma-ray observations of IceCube-240327A
  70. Fermi GRB 240405B: Global MASTER-Net observations report
  71. GRB 240405B: Fermi GBM Final Real-time Localization
  72. GRB 240405A: Fermi GBM Final Real-time Localization
  73. GRB 240331A: GRBAlpha detection
  74. GRB 240403B: Glowbug gamma-ray detection
  75. GRB 240403A: Glowbug gamma-ray detection
  76. GRB 240403A: Fermi GBM Detection
  77. Fermi GRB 240404A: Global MASTER-Net observations report
  78. GRB 240404A: Fermi GBM Final Real-time Localization
  79. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  80. Fermi trigger No 733808041: Global MASTER-Net observations report
  81. Fermi GRB 240402A: Global MASTER-Net observations report
  82. GRB 240402A: Fermi GBM Final Real-time Localization
  83. GRB 240329A: Glowbug gamma-ray detection
  84. GRB 240331A: AstroSat CZTI detection
  85. GRB 240329A: AstroSat CZTI detection
  86. GRB 240331A: Fermi GBM Final Real-time Localization
  87. GRB 240329A: GRBAlpha detection
  88. Fermi trigger No 733366352: Global MASTER-Net observations report
  89. Fermi GRB 240329A: Global MASTER-Net observations report
  90. GRB 240329A: BALROG localization (Fermi Trigger 733441392 / GRB 240329905)
  91. GRB 240329A: Fermi GBM Final Real-time Localization
  92. Fermi GRB 240328B: Global MASTER-Net observations report
  93. Fermi GRB 240328A: Global MASTER-Net observations report
  94. GRB 240328B: Fermi GBM Final Real-time Localization
  95. GRB 240328A: Fermi GBM Final Real-time Localization
  96. IceCube-240327B - IceCube observation of a high-energy neutrino candidate track-like event
  97. IceCube-240327A - IceCube observation of a high-energy neutrino candidate track-like event
  98. Fermi trigger No 733097506: Global MASTER-Net observations report
  99. Fermi trigger No 733092476: Global MASTER-Net observations report
  100. GRB 240320A: Glowbug gamma-ray detection

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