Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. 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"

5553 results found.

  1. Fermi GRB 230307A: Global MASTER-Net observations report
  2. GRB 230307A: VZLUSAT-2 detection
  3. Fermi GRB 230308A: Global MASTER-Net observations report
  4. GRB 230307A: Detection by GRBAlpha
  5. GRB 230305A: Detection by GRBAlpha
  6. GRB 230307A: AstroSat CZTI detection
  7. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  8. GRB 230307A: AGILE/MCAL detection
  9. GRB 230307A: Fermi GBM Observation of a very bright burst
  10. Solar Orbiter STIX observation of GRB 230307A
  11. IceCube-230306A: Upper limits from a search for additional neutrino events in IceCube
  12. Fermi-LAT gamma-ray observations of IceCube-230306A
  13. GRB 230307A: GECAM detection of an extremely bright burst
  14. Fermi trigger No 699811746: Global MASTER-Net observations report
  15. IceCube-230306A - IceCube observation of a high-energy neutrino candidate
  16. IceCube Alert 230306.46: Global MASTER-Net observations report
  17. GRB 230304C: AstroSat CZTI detection
  18. GRB 230304B: AstroSat CZTI detection
  19. GRB 230304A: AstroSat CZTI detection
  20. GRB 230304B: Detection by GRBAlpha
  21. Fermi GRB 230301B: Global MASTER-Net observations report
  22. Fermi trigger No 699294715: Global MASTER-Net observations report
  23. GRB 230228A: OSN optical upper limit
  24. GRB 230227A: Fermi GBM Final Real-time Localization
  25. Fermi trigger No 699029364: Global MASTER-Net observations report
  26. GRB 230216A Mondy Observations
  27. IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
  28. GRB 230216B: CALET Gamma-Ray Burst Monitor detection
  29. GRB 230216B: AstroSat CZTI detection
  30. Fermi trigger No 697904388: Global MASTER-Net observations report
  31. Fermi trigger No 697403223: Global MASTER-Net observations report
  32. Fermi trigger No 697396830: Global MASTER-Net observations report
  33. Fermi Gamma-ray Burst Monitor triggers due to recent activity of RX J0440.9+4431 (LS V +44 17)
  34. GRB 230205A: SVOM/C-GFT optical upper limit
  35. GRB 230205A: OHP/T193 optical observations
  36. GRB 230204B: Detection by GRBAlpha
  37. IceCube-230201A: BOOTES-4/MET Optical Upper Limits
  38. Fermi trigger No 697208885: Global MASTER-Net observations report
  39. GRB 230201B: TURBO Optical Upper Limits
  40. Fermi Gamma-ray Burst Monitor trigger 230203275 / 697098930 is not a GRB
  41. Fermi trigger No 697098930: Global MASTER-Net observations report
  42. Fermi GRB 230201B: Global MASTER-Net observations report
  43. Fermi GRB 230201A: Global MASTER-Net observations report
  44. IceCube-230122A: BOOTES-2/TELMA Optical Upper Limit
  45. AT2023avj ZTF Candidate: Assy optical observations
  46. IceCube-230122A: Upper limits from a search for additional neutrino events in IceCube
  47. Fermi-LAT gamma-ray observations of IceCube-230122A
  48. IceCube-230122A - IceCube observation of a high-energy neutrino candidate track-like event
  49. IceCube-Cascade 230109A: Upper limits from a search for additional neutrino events in IceCube
  50. Fermi trigger No 695057654: Global MASTER-Net observations report
  51. GRB 230104A: AGILE/MCAL detection of a burst
  52. GRB 221230A: CALET Gamma-Ray Burst Monitor detection
  53. IceCube-221224A: Upper limits from a search for additional neutrino events in IceCube
  54. Fermi GRB 221221A: Global MASTER-Net observations report
  55. IceCube-221210A: BOOTES-4/MET and Lijiang 2.4-meter Telescopes Optical Observations
  56. Fermi trigger No 692713692: Global MASTER-Net observations report
  57. Swift Trigger 1144538 is not a GRB
  58. Fermi GRB 221211A: Global MASTER-Net observations report
  59. GRB 221208A: AstroSat CZTI detection
  60. GRB 221209B: Fermi GBM Final Real-time Localization
  61. GRB 221203C: AstroSat CZTI detection
  62. GRB 221202B: Detection by VZLUSAT-2
  63. GRB 221202A: MeerLICHT upper limits
  64. IceCube Alert 221124.66: Global MASTER-Net observations report
  65. GRB 221115A: Fermi GBM detection
  66. GRB 221110A: COATLI Second-Epoch Upper Limits
  67. GRB 221110A: COATLI Afterglow detection
  68. GRB 221110A: LCOGT Optical Afterglow Detection
  69. IceCube-221104A: Upper limits from a search for additional neutrino events in IceCube
  70. GRB 221028A: COATLI Upper Limits
  71. GRB 221028A: Swift detection of a burst
  72. GRB 221024A: Mondy optical observations
  73. IPN triangulation of GRB 221022C (short)
  74. LAT GRB221025.04: Global MASTER-Net observations report
  75. GRB221009A: LBT optical imaging
  76. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  77. GRB 221017A: MAXI/GSC detection
  78. GRB 221009A: Armchair Energetics
  79. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  80. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  81. Fermi trigger No 687345829: Global MASTER-Net observations report
  82. Fermi trigger No 687344475: Global MASTER-Net observations report
  83. Fermi trigger No 687340841: Global MASTER-Net observations report
  84. Fermi trigger No 687337536: Global MASTER-Net observations report
  85. Fermi trigger No 687281393: Global MASTER-Net observations report
  86. GRB 221009A/Swift J1913.1+1946: SMA observations
  87. GRB 221009A: NuSTAR Detection
  88. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  89. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  90. GRB 221009A: Fermi-LAT refined analysis
  91. Swift J1913.1+1946 : Pre-discovery limits from ZTF
  92. Fermi trigger No 687014224: Global MASTER-Net observations report
  93. Fermi trigger No 686403226: Global MASTER-Net observations report
  94. Fermi trigger No 686350260: Global MASTER-Net observations report
  95. Ultra-long GRB 220525B: Konus-Wind and Fermi-GBM detection
  96. Fermi GRB 220925A: Global MASTER-Net observations report
  97. Fermi trigger No 685748699: Global MASTER-Net observations report
  98. Fermi trigger No 684894705: Global MASTER-Net observations report
  99. IceCube-220907A: No significant detection in HAWC
  100. Fermi GRB 220912A: Global MASTER-Net observations report

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