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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"

5556 results found.

  1. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  2. GRB 230308A: AGILE/MCAL detection
  3. GRB 230307A: Upper limits from a neutrino search with IceCube
  4. Fermi GRB 230307A: Global MASTER-Net observations report
  5. GRB 230307A: VZLUSAT-2 detection
  6. Fermi GRB 230308A: Global MASTER-Net observations report
  7. GRB 230307A: Detection by GRBAlpha
  8. GRB 230305A: Detection by GRBAlpha
  9. GRB 230307A: AstroSat CZTI detection
  10. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  11. GRB 230307A: AGILE/MCAL detection
  12. GRB 230307A: Fermi GBM Observation of a very bright burst
  13. Solar Orbiter STIX observation of GRB 230307A
  14. IceCube-230306A: Upper limits from a search for additional neutrino events in IceCube
  15. Fermi-LAT gamma-ray observations of IceCube-230306A
  16. GRB 230307A: GECAM detection of an extremely bright burst
  17. Fermi trigger No 699811746: Global MASTER-Net observations report
  18. IceCube-230306A - IceCube observation of a high-energy neutrino candidate
  19. IceCube Alert 230306.46: Global MASTER-Net observations report
  20. GRB 230304C: AstroSat CZTI detection
  21. GRB 230304B: AstroSat CZTI detection
  22. GRB 230304A: AstroSat CZTI detection
  23. GRB 230304B: Detection by GRBAlpha
  24. Fermi GRB 230301B: Global MASTER-Net observations report
  25. Fermi trigger No 699294715: Global MASTER-Net observations report
  26. GRB 230228A: OSN optical upper limit
  27. GRB 230227A: Fermi GBM Final Real-time Localization
  28. Fermi trigger No 699029364: Global MASTER-Net observations report
  29. GRB 230216A Mondy Observations
  30. IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
  31. GRB 230216B: CALET Gamma-Ray Burst Monitor detection
  32. GRB 230216B: AstroSat CZTI detection
  33. Fermi trigger No 697904388: Global MASTER-Net observations report
  34. Fermi trigger No 697403223: Global MASTER-Net observations report
  35. Fermi trigger No 697396830: Global MASTER-Net observations report
  36. Fermi Gamma-ray Burst Monitor triggers due to recent activity of RX J0440.9+4431 (LS V +44 17)
  37. GRB 230205A: SVOM/C-GFT optical upper limit
  38. GRB 230205A: OHP/T193 optical observations
  39. GRB 230204B: Detection by GRBAlpha
  40. IceCube-230201A: BOOTES-4/MET Optical Upper Limits
  41. Fermi trigger No 697208885: Global MASTER-Net observations report
  42. GRB 230201B: TURBO Optical Upper Limits
  43. Fermi Gamma-ray Burst Monitor trigger 230203275 / 697098930 is not a GRB
  44. Fermi trigger No 697098930: Global MASTER-Net observations report
  45. Fermi GRB 230201B: Global MASTER-Net observations report
  46. Fermi GRB 230201A: Global MASTER-Net observations report
  47. IceCube-230122A: BOOTES-2/TELMA Optical Upper Limit
  48. AT2023avj ZTF Candidate: Assy optical observations
  49. IceCube-230122A: Upper limits from a search for additional neutrino events in IceCube
  50. Fermi-LAT gamma-ray observations of IceCube-230122A
  51. IceCube-230122A - IceCube observation of a high-energy neutrino candidate track-like event
  52. IceCube-Cascade 230109A: Upper limits from a search for additional neutrino events in IceCube
  53. Fermi trigger No 695057654: Global MASTER-Net observations report
  54. GRB 230104A: AGILE/MCAL detection of a burst
  55. GRB 221230A: CALET Gamma-Ray Burst Monitor detection
  56. IceCube-221224A: Upper limits from a search for additional neutrino events in IceCube
  57. Fermi GRB 221221A: Global MASTER-Net observations report
  58. IceCube-221210A: BOOTES-4/MET and Lijiang 2.4-meter Telescopes Optical Observations
  59. Fermi trigger No 692713692: Global MASTER-Net observations report
  60. Swift Trigger 1144538 is not a GRB
  61. Fermi GRB 221211A: Global MASTER-Net observations report
  62. GRB 221208A: AstroSat CZTI detection
  63. GRB 221209B: Fermi GBM Final Real-time Localization
  64. GRB 221203C: AstroSat CZTI detection
  65. GRB 221202B: Detection by VZLUSAT-2
  66. GRB 221202A: MeerLICHT upper limits
  67. IceCube Alert 221124.66: Global MASTER-Net observations report
  68. GRB 221115A: Fermi GBM detection
  69. GRB 221110A: COATLI Second-Epoch Upper Limits
  70. GRB 221110A: COATLI Afterglow detection
  71. GRB 221110A: LCOGT Optical Afterglow Detection
  72. IceCube-221104A: Upper limits from a search for additional neutrino events in IceCube
  73. GRB 221028A: COATLI Upper Limits
  74. GRB 221028A: Swift detection of a burst
  75. GRB 221024A: Mondy optical observations
  76. IPN triangulation of GRB 221022C (short)
  77. LAT GRB221025.04: Global MASTER-Net observations report
  78. GRB221009A: LBT optical imaging
  79. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  80. GRB 221017A: MAXI/GSC detection
  81. GRB 221009A: Armchair Energetics
  82. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  83. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  84. Fermi trigger No 687345829: Global MASTER-Net observations report
  85. Fermi trigger No 687344475: Global MASTER-Net observations report
  86. Fermi trigger No 687340841: Global MASTER-Net observations report
  87. Fermi trigger No 687337536: Global MASTER-Net observations report
  88. Fermi trigger No 687281393: Global MASTER-Net observations report
  89. GRB 221009A/Swift J1913.1+1946: SMA observations
  90. GRB 221009A: NuSTAR Detection
  91. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  92. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  93. GRB 221009A: Fermi-LAT refined analysis
  94. Swift J1913.1+1946 : Pre-discovery limits from ZTF
  95. Fermi trigger No 687014224: Global MASTER-Net observations report
  96. Fermi trigger No 686403226: Global MASTER-Net observations report
  97. Fermi trigger No 686350260: Global MASTER-Net observations report
  98. Ultra-long GRB 220525B: Konus-Wind and Fermi-GBM detection
  99. Fermi GRB 220925A: Global MASTER-Net observations report
  100. Fermi trigger No 685748699: Global MASTER-Net observations report

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