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"

3139 results found.

  1. GRB 221108A: Fermi GBM Final Localization
  2. Correction to GCN 32852 (GRB 221009A: SARA-RM 1m Optical Afterglow Detection)
  3. GRB 221027C: AstroSat CZTI detection
  4. SGR 1935+2154: AstroSat CZTI Detections
  5. GRB 221025A: AstroSat CZTI detection
  6. LAT GRB221025.04: Global MASTER-Net observations report
  7. GRB 221022B: AstroSat CZTI detection
  8. GRB 221009A: Determination of the black holes mass and spin
  9. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  10. GRB 221009A: A type I BdHN of exceptional energetics
  11. GRB 221016A: Swift detection of a burst
  12. Konus-Wind observation of the recent SGR 1935+2154 activity
  13. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  14. GRB 221009A: Gemini-South Infrared Afterglow Detection
  15. MAXI GRB 221006A: Redshifts of the possible host galaxies
  16. GRB 221006A: Swift-XRT afterglow detection
  17. GRB 221013A: Fermi GBM Final Real-time Localization
  18. Afterglow limits of GRB 221006A from OHP
  19. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  20. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  21. GRB 221009A (Swift J1913.1+1946): AGILE/GRID detection
  22. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  23. GRB 221006A: Swift-XRT observations
  24. GRB 221006A: MAXI/GSC detection
  25. Fermi trigger No 686403226: Global MASTER-Net observations report
  26. Fermi trigger No 686350260: Global MASTER-Net observations report
  27. GRB 220930A: AstroSat CZTI detection
  28. GRB 220930A: LCOGT Optical Upper Limits
  29. Fermi GRB 220925A: Global MASTER-Net observations report
  30. Fermi trigger No 685748699: Global MASTER-Net observations report
  31. LAT GRB220921.46: Global MASTER-Net observations report
  32. Fermi trigger No 684716840: Global MASTER-Net observations report
  33. Fermi GRB 220912A: Global MASTER-Net observations report
  34. GRB 220912A: AstroSat CZTI detection
  35. IPN triangulation of GRB 220905A
  36. GRB 220910A: AstroSat CZTI detection
  37. IPN triangulation of GRB 220903A (long)
  38. Fermi GRB 220902A: Global MASTER-Net observations report
  39. Fermi trigger No 683646997: Global MASTER-Net observations report
  40. IceCube-220822A: No significant detection in HAWC
  41. Fermi trigger No 683202084: Global MASTER-Net observations report
  42. Fermi trigger No 683183601: Global MASTER-Net observations report
  43. Fermi trigger No 682918137: Global MASTER-Net observations report
  44. Fermi trigger No 681998863: Global MASTER-Net observations report
  45. GRB 220810A: MeerLICHT detection of two afterglow candidates
  46. GRB 220810A: Fermi GBM Final Real-time Localization
  47. IceCube Alert 220808.33: Global MASTER-Net observations report
  48. GRB 220803A: AstroSat CZTI detection
  49. GRB 220729A: AstroSat CZTI detection
  50. Fermi trigger No 680782656: Global MASTER-Net observations report
  51. Fermi GRB 220728A: Global MASTER-Net observations report
  52. GRB 220726A: Fermi GBM Final Real-time Localization
  53. Fermi GRB 220724A: Global MASTER-Net observations report
  54. Fermi GRB 220721A: Global MASTER-Net observations report
  55. GRB 220715B: Swift detection of a burst
  56. GRB 220715B: Fermi GBM Final Real-time Localization
  57. Fermi GRB 220711B: Global MASTER-Net observations report
  58. GRB 220707A: AstroSat CZTI detection
  59. GRB 220702B: AstroSat CZTI detection
  60. MAXI GRB220706.73: Global MASTER-Net observations report
  61. GRB 220627A: AstroSat CZTI detection
  62. Fermi trigger No 678058621: Global MASTER-Net observations report
  63. Fermi GRB 220624A: Global MASTER-Net observations report
  64. IceCube Alert 220624.68: Global MASTER-Net observations report
  65. GRB 220623A: AstroSat CZTI detection
  66. GRB 220623A: iTelescope optical upper limit
  67. GRB 220623A: Swift detection of a burst
  68. Fermi trigger No 677377371: Global MASTER-Net observations report
  69. GRB 220619A: AstroSat CZTI detection
  70. GRB 220610B: AstroSat CZTI detection
  71. Fermi GRB 220610A: Global MASTER-Net observations report
  72. Fermi trigger No 676537486: Global MASTER-Net observations report
  73. GRB 220609B: AstroSat CZTI detection
  74. GRB 220608A: AstroSat CZTI detection
  75. MAXI GRB220607.31: Global MASTER-Net observations report
  76. MAXI GRB220607.41: Global MASTER-Net observations report
  77. GRB 220527A: A BdHN I with a clear UPE phase
  78. GRB 220527A: AstroSat CZTI detection
  79. IPN triangulation of GRB 220525A
  80. GRB 220514A: AstroSat CZTI detection
  81. Fermi GRB 220513A: Global MASTER-Net observations report
  82. GRB 220511A: AstroSat CZTI detection
  83. Fermi GRB 220511A: Global MASTER-Net observations report
  84. GRB 220507A: AstroSat CZTI detection
  85. Fermi trigger No 673846271: Global MASTER-Net observations report
  86. GRB 220506A: MITSuME Akeno optical upper limits
  87. IPN triangulation of GRB 220423A
  88. IceCube-220501A: Upper limits from a search for additional neutrino events in IceCube
  89. GRB 220430A: AstroSat CZTI detection
  90. GRB 220430A: Swift-BAT refined analysis
  91. Fermi GRB 220426A: Global MASTER-Net observations report
  92. Fermi trigger No 672093919: Global MASTER-Net observations report
  93. Konus-Wind detection of GRB 220412B
  94. GRB 220412B: TNG optical observations
  95. GRB 220408B: Fermi-LAT detection
  96. GRB 220411A: AstroSat CZTI detection
  97. GRB 220408B: AstroSat CZTI detection
  98. Fermi GRB 220408B: Global MASTER-Net observations report
  99. GRB 220408A: Fermi GBM Final Real-time Localization
  100. IceCube Alert 220405.93: Global MASTER-Net observations report

Advanced

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