Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

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"

3140 results found.

  1. IceCube Alert 220405.93: Global MASTER-Net observations report
  2. IceCube Alert 220405.21: Global MASTER-Net observations report
  3. GRB 220403B: Fermi GBM detection
  4. GRB 220403B: Swift detection of a burst with an optical counterpart
  5. Swift Trigger 1100848 is likely not a GRB
  6. Fermi GRB 220330A: Global MASTER-Net observations report
  7. GRB 220324A: AstroSat CZTI detection
  8. GRB 220323A: AstroSat CZTI detection
  9. GRB 220316A: AstroSat CZTI detection
  10. GRB 220320A: AstroSat CZTI detection
  11. GRB 220319A: MITSuME Akeno optical upper limits
  12. GRB 220319A: Swift detection of a burst
  13. IceCube-220317A: MASTER Global Robotic Net optical observations
  14. GRB 220310C: Fermi GBM Final Real-time Localization
  15. Fermi GBM Detection of GRB 220308A
  16. GRB 220310A: MAXI/GSC detection
  17. IPN triangulation of GRB 220308A (long / very bright)
  18. GRB 220306B: Mondy optical observations, confirmation afterglow candidate
  19. Fermi trigger No 668410535: Global MASTER-Net observations report
  20. GRB 220305A: Swift-BAT refined analysis
  21. GRB 220305A: Swift detection of a burst
  22. IceCube Alert 220304.74: Global MASTER-Net observations report
  23. Fermi GRB 220304A: Global MASTER-Net observations report
  24. GRB 220304A: Fermi GBM Final Real-time Localization
  25. IPN triangulation of GRB 220222A
  26. GCN Circ.draft on GRB 220222A
  27. Fermi GRB 220223A: Global MASTER-Net observations report
  28. ZTF22aaajecp/AT2022cmc: Swift Observation and a UV Detection
  29. IceCube-220221A: Upper limits from a search for additional neutrino events in IceCube
  30. Fermi GRB 220222B: Global MASTER-Net observations report
  31. Fermi-LAT Gamma-ray Observations of IceCube-220221A
  32. IceCube-220221A - IceCube observation of a high-energy neutrino candidate track-like event
  33. IceCube Alert 220220.60: Global MASTER-Net observations report
  34. GRB 220211A: MASTER optical observations of ZTF22aaajecp/AT2022cmc
  35. ZTF22aaajecp/AT2022cmc: Liverpool Telescope photometry
  36. ZTF22aaajecp/AT2022cmc: Zwicky Transient Facility discovery of a fast and red optical transient
  37. GRB 211227A: Konus-Wind detection and joint Konus-Wind+Swift-BAT spectral analysis
  38. IceCube Alert 220202.49: Global MASTER-Net observations report
  39. GRB 220128A: AstroSat CZTI detection
  40. IPN triangulation of GRB 220128A (long)
  41. GRB 220124A: AstroSat CZTI detection of a bright long GRB
  42. GRB 220117B: TARGET optical upper limit
  43. GRB 220101A: TSHAO optical observation, Terskol, AbAO upper limits
  44. GECAM observations of a series of bursts from SGR J1935+2154
  45. Fermi-GBM Observations of Recent Bursting Activity from SGR J1935+2154
  46. GECAM observations of a series of bursts from SGR J1935+2154
  47. GRB 220111A: AstroSat CZTI detection
  48. Fermi GRB 220111A: Global MASTER-Net observations report
  49. Fermi trigger No 663406755: Global MASTER-Net observations report
  50. GRB 220107A: AbAO and Terskol optical observations
  51. GRB 220107B: AstroSat CZTI detection
  52. GRB 220107A: AstroSat CZTI detection
  53. Fermi GRB 220107A: Global MASTER-Net observations report
  54. Fermi GRB 220104A: Global MASTER-Net observations report
  55. GRB 211231A: AstroSat CZTI detection
  56. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  57. GRB 211227A: BOOTES-2/TELMA optical upper limit
  58. GRB 211227A: Swift detection of a burst
  59. GRB 211225A: MITSuME Akeno optical upper limits
  60. Fermi trigger No 662084433: Global MASTER-Net observations report
  61. AGILE observations of a bright burst from SGR 1935+2154
  62. Swift GRB 211223C: Global MASTER-Net observations report
  63. GRB 211219B: AstroSat CZTI detection
  64. GRB 211219A: AstroSat CZTI detection
  65. GRB 211218A: MITSuME Akeno optical upper limits
  66. Fermi GRB 211219B: Global MASTER-Net observations report
  67. Fermi GRB 211211B: Global MASTER-Net observations report
  68. GRB 211211B: Fermi GBM Final Real-time Localization
  69. Fermi trigger No 660868196: Global MASTER-Net observations report
  70. Fermi trigger No 660736561: Global MASTER-Net observations report
  71. GRB 211206A: AstroSat CZTI detection
  72. GRB 211206B: AstroSat CZTI detection
  73. GRB 211204C: AstroSat CZTI detection
  74. Fermi GRB 211204C: Global MASTER-Net observations report
  75. Fermi GRB 211204B: Global MASTER-Net observations report
  76. GRB 211201A: Swift/BAT-GUANO detection likely outside the coded FOV
  77. GRB 211201A: Fermi GBM Final Real-time Localization
  78. IceCube Alert 211125.27: Global MASTER-Net observations report
  79. GRB 211120A: AstroSat CZTI detection
  80. GRB 211118A: AstroSat CZTI detection
  81. Fermi trigger No 658971499: Global MASTER-Net observations report
  82. Fermi trigger No 658755664: Global MASTER-Net observations report
  83. GRB 211115A: MAXI/GSC detection
  84. Fermi GRB 211112A: Global MASTER-Net observations report
  85. GRB 211110A: AstroSat CZTI detection
  86. Fermi trigger No 658214822: Global MASTER-Net observations report
  87. GRB 211109B: Fermi GBM Final Real-time Localization
  88. GRB 211023A: A BdHN of type I
  89. GRB 211024A: MITSuME Akeno optical observation
  90. Fermi GRB 211031A: Global MASTER-Net observations report
  91. GRB 211023B: LDT Optical Afterglow Detection
  92. GRB 211022A: AstroSat CZTI detection
  93. Fermi GRB 211024A: Global MASTER-Net observations report
  94. Fermi trigger No 656506979: Global MASTER-Net observations report
  95. Fermi GRB 211019A: Global MASTER-Net observations report
  96. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  97. Swift Trigger 1078701 is probably not a GRB
  98. Fermi trigger No 654658271: Global MASTER-Net observations report
  99. Fermi GRB 210929B: Global MASTER-Net observations report
  100. GRB 210929B: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov