Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. See news and announcements

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"

36393 results found.

  1. GRB 230101A: Fermi GBM Final Real-time Localization
  2. GRB 221231A: Fermi GBM Final Real-time Localization
  3. GRB 221226A: Fermi GBM detection
  4. IPN triangulation of GRB 221226A
  5. GRB 221226A: Swift/BAT-GUANO detection outside the coded FOV
  6. GRB 221226B: LCOGT Optical Upper Limits
  7. GRB 221228A: Fermi GBM Final Real-time Localization
  8. GRB 221226B Swift-BAT refined analysis
  9. GRB 221226B: Swift-UVOT Detection
  10. GRB 221226A: AGILE detection
  11. GRB 221226B: Fermi GBM Observation
  12. GRB 221226B: Swift-XRT refined Analysis
  13. GRB 221226B: VLT/X-shooter redshift and host galaxy
  14. GRB 221226B: Enhanced Swift-XRT position
  15. GRB 221226B: Swift detection of a burst
  16. GRB 221226B: Fermi GBM Final Real-time Localization
  17. Fermi GRB 221226A: Global MASTER-Net observations report
  18. GRB 221226A: Fermi GBM Final Real-time Localization
  19. Fermi GRB 221223A: Global MASTER-Net observations report
  20. GRB 221223A: Fermi GBM Final Real-time Localization
  21. GRB 221221A: AGILE detection
  22. Fermi GRB 221221A: Global MASTER-Net observations report
  23. GRB 221221A: Fermi GBM Final Real-time Localization
  24. GRB 221218A: 3.6m DOT optical upper limit
  25. GRB 221216A: Detection by VZLUSAT-2
  26. GRB 221218A: MITSuME Akeno optical upper limits
  27. GRB 221218A: BOOTES-4/MET and OSN optical upper limits
  28. GRB 221218A: KAIT Optical Upper Limit
  29. GRB 221215A: Fermi GBM Detection
  30. GRB 221218A: a long GRB detected by INTEGRAL
  31. GRB 221216A: Swift/UVOT Upper Limits
  32. GRB 221216A: Fermi GBM observation
  33. GRB 221216A: Swift-XRT refined Analysis
  34. GRB 221216A: AKO Upper Limit
  35. GRB 221215A: Swift-XRT observations
  36. GRB 221216A: Enhanced Swift-XRT position
  37. Swift GRB 221216A: Global MASTER-Net observations report
  38. GRB 221216A: Zadko observatory - Gingin optical observations
  39. GRB 221216A: Nanshan/NEXT optical upper limits
  40. GRB 221216A: Swift detection of a burst
  41. GRB 221216A: Fermi GBM Final Real-time Localization
  42. GRB 221215A: Swift ToO observations
  43. GRB 221215A: Swift/BAT-GUANO arcminute localization
  44. Konus-Wind detection of GRB 221209A
  45. Fermi GRB 221215B: Global MASTER-Net observations report
  46. IPN triangulation of GRB 221209A (long)
  47. GRB 221215B: Fermi GBM Final Real-time Localization
  48. Fermi Gamma-ray Burst Monitor trigger 692760884/221215066 is not a GRB
  49. GRB 221215A: Fermi GBM Final Real-time Localization
  50. Swift Trigger 1144538 is not a GRB
  51. GRB 221209A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 221212A: Fermi GBM Final Real-time Localization
  53. Fermi GRB 221211A: Global MASTER-Net observations report
  54. GRB 221208A: AstroSat CZTI detection
  55. GRB 221211A: Fermi GBM Final Real-time Localization
  56. GRB 221009A: MuSCAT3 observations
  57. GRB 221209A: AstroSat CZTI detection
  58. GRB 221210A: Fermi GBM Final Real-time Localization
  59. GRB 221209B: Fermi GBM Final Real-time Localization
  60. GRB 221209A: Fermi GBM observation
  61. GRB 221203C: AstroSat CZTI detection
  62. GRB 221209A: BALROG localization (Fermi Trigger 692257829 / GRB 221209243)
  63. GRB 221209A: Fermi GBM Final Real-time Localization
  64. GRB 221206B: Fermi GBM observation
  65. GRB 221206B: Swift-XRT observations
  66. GRB 221206B: Detection by GRBAlpha
  67. GRB 221206B: Swift/BAT-GUANO candidate arcminute localization
  68. GRB 221206B: Swift ToO observations
  69. Swift/BAT trigger #1143281 is not a GRB
  70. GRB 221206C: Fermi GBM Final Real-time Localization
  71. GRB 221206B: Fermi GBM Final Real-time Localization
  72. GRB 221206A: Fermi GBM Final Real-time Localization
  73. GRB 221205A: Fermi GBM Final Real-time Localization
  74. GRB 221202B: Detection by VZLUSAT-2
  75. GRB 221203B: Fermi GBM Final Real-time Localization
  76. GRB 221202A: Swift/UVOT Detection
  77. GRB 221202A: Swift-BAT refined analysis
  78. GRB 221202A: VLT/FORS2 Afterglow Discovery
  79. GRB 221201A: Swift-BAT refined analysis
  80. GRB 221203A: Fermi GBM Final Real-time Localization
  81. GRB 221201A: Fermi GBM observation
  82. GRB 221202A: Swift-XRT refined Analysis
  83. GRB 221202A: LCOGT Optical Upper Limits
  84. GRB 221202A: Enhanced Swift-XRT position
  85. GRB 221202A: MeerLICHT upper limits
  86. GRB 221202B: Fermi GBM Final Real-time Localization
  87. GRB 221202A: Swift detection of a burst
  88. GCN: GRB 221201A: Swift/UVOT Upper Limits
  89. GRB 221201A: Swift-XRT refined Analysis
  90. GRB 221201A: Enhanced Swift-XRT position
  91. Swift GRB 221201A: Global MASTER-Net observations report
  92. Konus-Wind detection of GRB 221124A
  93. GRB 221201A: Swift detection of a burst
  94. GRB 221201A: Fermi GBM Final Real-time Localization
  95. Fermi Gamma-ray Burst Monitor trigger 691534074/221130867 is not a GRB
  96. Optical polarization observation of GRB 221009A
  97. GRB 221126A: Fermi GBM observation
  98. GRB 221126A: AGILE detection
  99. GRB 221127A: Detection by GRBAlpha
  100. GRB 221126A: AstroSat CZTI detection

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov