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"

24619 results found.

  1. GRB 210928A: Kinder SLT-40cm optical limits
  2. GRB 210930A: Swift-BAT refined analysis
  3. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  4. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  5. GRB 210928A: Fermi GBM observation
  6. GRB 210928A: Fermi-LAT detection
  7. GRB 210927B: GECAM detection
  8. Fermi trigger No 654739449: Global MASTER-Net observations report
  9. Swift GRB211001.03: Global MASTER-Net observations report
  10. Swift GRB211001.03: Global MASTER-Net OT detection
  11. Swift GRB 210930A: Global MASTER-Net observations report
  12. Fermi trigger No 654658271: Global MASTER-Net observations report
  13. Fermi GRB 210929B: Global MASTER-Net observations report
  14. GRB 210929B: Fermi GBM Final Real-time Localization
  15. Fermi-LAT Gamma-ray Observations of IceCubeCascade-210926A
  16. GRB 210929A: Fermi GBM Final Real-time Localization
  17. GRB 210927A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 654396242)
  18. IPN triangulation of GRB 210925B
  19. IceCube-210926A: No neutrino counterpart candidates in ANTARES search
  20. GRB 210926A: GECAM detection
  21. GRB 210927A: Fermi GBM Final Real-time Localization
  22. GRB 210925A: GECAM detection
  23. GRB 210925A: Fermi GBM Final Real-time Localization
  24. GRB 210924A: Fermi GBM Final Real-time Localization
  25. IceCube-210922A: No significant detection in HAWC
  26. IceCube-210922A: No neutrino counterpart candidates in ANTARES search
  27. GRB 210923B: GECAM detection
  28. IceCube-210922A: Upper limits from a search for additional neutrino events in IceCube
  29. IceCube-210922A: Upper limits from Fermi-GBM Observations
  30. IceCube-210922A: No Candidate Counterparts from the Zwicky Transient Facility
  31. GECAM observations of a series of bursts from SGR J1935+2154 (2021-09-15T14 to 2021-09-23T14)
  32. Fermi-LAT Gamma-ray Observations of IceCube-210922A
  33. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 September 22
  34. GRB 210923A: Fermi GBM Final Real-time Localization
  35. IceCube Alert 210922.76: Global MASTER-Net observations report
  36. GRB 210919A: Swift-BAT refined analysis
  37. IceCube-210922A - IceCube observation of a high-energy neutrino candidate track-like event
  38. GRB 210919A: MITSuME Akeno optical upper limits
  39. GRB 210919A: Swift-XRT refined Analysis
  40. GRB 210919B: Fermi GBM Final Real-time Localization
  41. GRB 210919A: LCO Optical Upper Limit
  42. Swift GRB 210919A: Global MASTER-Net observations report
  43. GRB 210919A: Swift detection of a short burst
  44. GRB 210917A: Fermi GBM Final Real-time Localization
  45. GECAM observations of bursts from SGR J1935+2154 (2021-09-13T01 to 2021-09-15T14)
  46. GRB 210909A: Detection by GRBAlpha
  47. GRB 210912A: Swift-BAT refined analysis
  48. Konus-Wind observation of the recent SGR 1935+2154 activity
  49. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  50. GRB 210912A: CAHA 2.2m Detection
  51. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  52. Fermi trigger No 653151835: Global MASTER-Net observations report
  53. Fermi trigger No 653124492: Global MASTER-Net observations report
  54. Fermi trigger No 653122278: Global MASTER-Net observations report
  55. Swift GRB 210912A: Global MASTER-Net observations report
  56. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  57. GRB 210912B: Fermi GBM Final Real-time Localization
  58. Fermi trigger No 653093506: Global MASTER-Net observations report
  59. Fermi trigger No 653066776: Global MASTER-Net observations report
  60. Fermi trigger No 653084584: Global MASTER-Net observations report
  61. Fermi trigger No 653083551: Global MASTER-Net observations report
  62. Fermi trigger No 653079281: Global MASTER-Net observations report
  63. Fermi trigger No 653066130: Global MASTER-Net observations report
  64. Fermi trigger No 653072474: Global MASTER-Net observations report
  65. Fermi trigger No 653071808: Global MASTER-Net observations report
  66. Fermi trigger No 653054042: Global MASTER-Net observations report
  67. Fermi trigger No 653049776: Global MASTER-Net observations report
  68. Fermi trigger No 653022153: Global MASTER-Net observations report
  69. Fermi trigger No 653031163: Global MASTER-Net observations report
  70. Swift GRB210910.42: Global MASTER-Net observations report
  71. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  72. Fermi trigger No 653010039: Global MASTER-Net observations report
  73. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  74. IPN triangulation of a bright burst from SGR 1935+2154
  75. Fermi trigger No 652957973: Global MASTER-Net observations report
  76. Fermi trigger No 652944960: Global MASTER-Net observations report
  77. Fermi trigger No 652981861: Global MASTER-Net observations report
  78. GRB 210909B: GECAM detection
  79. GECAM observations of a series of bursts from SGR J1935+2154
  80. Fermi trigger No 652934203: Global MASTER-Net observations report
  81. GECAM observation of a burst from SGR J1935+2154
  82. GECAM observation of a burst from SGR J1935+2154
  83. Fermi trigger No 652927551: Global MASTER-Net observations report
  84. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  85. Fermi trigger No 652911693: Global MASTER-Net observations report
  86. Fermi trigger No 652906639: Global MASTER-Net observations report
  87. Fermi GRB 210909A: Global MASTER-Net observations report
  88. GECAM observation of a burst from SGR J1555.2-5402
  89. GRB 210909A: Fermi GBM Final Real-time Localization
  90. GRB 210905A: ATCA detection
  91. GRB 210905A, GROND observations
  92. Konus-Wind detection of GRB 210905A
  93. Fermi GBM Sub-Threshold Detection of GRB 210905A
  94. Fermi trigger No 652585475: Global MASTER-Net observations report
  95. GRB 210905A: Swift-XRT refined Analysis
  96. GRB 210610A: Maidanak and AbAO optical observations
  97. GRB 210827B: GECAM detection
  98. GRB 210905A: REM NIR afterglow detection
  99. GRB 210905A: Continued LCO Optical Observations
  100. GRB 210905A: LCO Optical 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