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"

14986 results found.

  1. GRB 210909A: Detection by GRBAlpha
  2. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  3. GRB 210912A: CAHA 2.2m Detection
  4. GRB 210912A: Swift/UVOT Detection
  5. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  6. GRB 210912B: Fermi GBM Final Real-time Localization
  7. GRB 210912A: Swift detection of a burst
  8. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  9. GRB 210909B: GECAM detection
  10. GECAM observations of a series of bursts from SGR J1935+2154
  11. Swift detection of a burst from SGR Swift J1555.2-5402
  12. GECAM observation of a burst from SGR J1935+2154
  13. GECAM observation of a burst from SGR J1935+2154
  14. GECAM observation of a burst from SGR J1555.2-5402
  15. GRB 210909A: Fermi GBM Final Real-time Localization
  16. GRB 210905A: ATCA detection
  17. GRB 210905A: ALMA detection
  18. GRB 210905A: AstroSat CZTI detection
  19. Konus-Wind detection of GRB 210905A
  20. Fermi GBM Sub-Threshold Detection of GRB 210905A
  21. GRB 210827B: GECAM detection
  22. GRB 210905A: DECam Detection
  23. GRB 210905A: REM NIR afterglow detection
  24. GRB 210905A: VLT/X-shooter spectroscopic redshift
  25. GRB 210905A: LCO Optical Detection
  26. GRB 210905A: Swift detection of a burst
  27. GRB 210904A: Fermi GBM Final Real-time Localization
  28. GRB 210903C: Fermi GBM Final Real-time Localization
  29. GRB 210903B: Fermi GBM Final Localization
  30. GRB 210903A: Fermi GBM Final Real-time Localization
  31. GRB 210901A: LCO Optical Upper Limit
  32. GRB 210901A: Swift detection of a burst
  33. GRB 210822A: CALET Gamma-Ray Burst Monitor detection
  34. GRB 210827A: BOOTES-5/JGT optical upper limit
  35. GRB 210826A: AstroSat CZTI detection
  36. GRB 210827A: Swift/BAT-GUANO detection and arcminute localization
  37. GRB 210820A: CAHA 2.2m Optical Detection
  38. POLAR detection of a SGR-like burst
  39. GRB 210827B: Fermi GBM Final Real-time Localization
  40. GRB 210827A: Fermi GBM Final Real-time Localization
  41. GRB 210822A: CAHA 2.2m observations
  42. GRB 210826A: Fermi-LAT detection
  43. GRB 210826A: Fermi GBM Final Real-time Localization
  44. GRB 210822A: VLA detection
  45. Swift detection of an outburst from SGR Swift J1555.2-5402
  46. GRB 210822A: Swift/UVOT Detection
  47. GRB 210824A: Swift detection of a burst
  48. GRB 210824A: Fermi GBM Final Real-time Localization
  49. GRB 210822A: Detection by GRBAlpha
  50. GRB 210822A: GECAM refined analysis
  51. GRB 210820A: GROND observations
  52. Konus-Wind detection of GRB 210822A
  53. GRB 210822A: AstroSat CZTI detection
  54. GRB 210820A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  55. GRB 210822A: Fermi-LAT detection
  56. GRB 210820A: Swift/UVOT Detection
  57. GRB 210822B: Fermi GBM Final Real-time Localization
  58. GRB 210822A: KAIT Optical Afterglow Confirmation
  59. GRB 210822A: GECAM detection
  60. GRB 210822A: Swift detection of a burst with an optical afterglow
  61. GRB 210820A: LCO Optical Upper Limit
  62. GRB 210821A: Fermi GBM Final Real-time Localization
  63. GRB 210820B: Fermi GBM Final Localization
  64. GRB 210820A: Swift detection of a burst with an optical counterpart
  65. GRB 210726A: VLA radio afterglow detection
  66. Konus-Wind detection of GRB 210818A
  67. GRB 210818A: AstroSat CZTI detection
  68. GRB 210818A: AGILE detection
  69. GRB 210818A: Swift detection of a burst with an optical counterpart
  70. GRB 210815A: Fermi GBM Final Real-time Localization
  71. GRB 210813A: Fermi GBM Final Real-time Localization
  72. GRB 210812B: Fermi GBM Final Real-time Localization
  73. GRB 210812A: Fermi GBM Final Real-time Localization
  74. GRB 080102A: Fermi GBM Final Real-time Localization
  75. GRB 080101A: Fermi GBM Final Real-time Localization
  76. GRB 210730A: Tautenburg observations
  77. IceCube-210811A - IceCube observation of a high-energy neutrino candidate track-like event
  78. GRB 210807A: Detection by GRBAlpha
  79. GRB 210807C: Fermi GBM detection
  80. GRB 210807A: Swift/UVOT Detection
  81. GRB 210807C: Swift detection of a burst
  82. GRB 210807C: Fermi GBM Final Real-time Localization
  83. GRB 210807A: BOOTES-5/JGT optical afterglow detection
  84. GRB 210807B: Fermi GBM Final Real-time Localization
  85. GRB 210807A: Swift detection of a burst with an optical counterpart
  86. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  87. GRB 210802A: Swift-XRT afterglow detection
  88. GRB 210802A: Fermi GBM detection
  89. GRB 210802A: Fermi-LAT detection
  90. GRB 210801A: Fermi GBM detection
  91. GRB 210731A: VLT/X-shooter redshift
  92. GRB 210731A: KAIT Optical Detection
  93. GRB 210731A: MASTER optical afterglow detection
  94. GRB 210731A: Swift/UVOT Detection of an optical afterglow
  95. GRB 210731A: MeerLICHT optical afterglow detection
  96. GRB 210731A: Swift detection of a burst
  97. Trigger 1062273: Swift detection of 4U 1700-377
  98. GRB 210730A: BOOTES-5/JGT and 2.2m CAHA telescopes optical limit
  99. IceCube-210730A - IceCube observation of a high-energy neutrino candidate track-like event
  100. GRB 210726A: Chandra detection of the X-ray afterglow

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