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"

36315 results found.

  1. GRB 240226A: GRBAlpha detection
  2. GRB 240225B: Mondy afterglow observations
  3. Fermi GRB 240227A: Global MASTER-Net observations report
  4. GRB 240225B: Liverpool Telescope afterglow observations
  5. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  6. Swift Trigger 1217799 is not a GRB
  7. IPN triangulation of GRB 240227A (short)
  8. GRB 240225B: Liverpool Telescope optical afterglow observations
  9. GRB 240225B: NOT optical observations
  10. GRB 240218A: CMO SAI NIR upper limit
  11. Fermi GRB 240226A: Global MASTER-Net observations report
  12. GRB 240227A: Fermi GBM Final Real-time Localization
  13. Fermi Gamma-ray Burst Monitor trigger 730618809/240226236 is not a GRB
  14. GRB 240225B: Nanshan/HMT optical afterglow detection
  15. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  16. GRB 240225B: Swift-XRT observations
  17. GRB 240226B: Fermi GBM Final Real-time Localization
  18. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  19. GRB 240225B: GOTO detection of a candidate optical afterglow
  20. GRB 240226A: Fermi GBM Final Real-time Localization
  21. GRB 240225C: GRBAlpha detection
  22. GRB 240222A: ATCA radio observations
  23. GRB 240225C: AstroSat CZTI detection
  24. GRB 240225B: AstroSat CZTI detection
  25. GRB 240225B: Tiled Swift observations
  26. GRB 240225B: MAXI/GSC detection
  27. GRB 240218A: VLA detection
  28. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  29. GRB 240222A: GRBAlpha detection
  30. VLA X-band observation of EPW20240219aa
  31. Transient EPW20240219aa: Mondy optical observations
  32. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  33. Swift BAT Sub-Threshold Detection of EPW20240219aa
  34. GRB 240222A: GECAM detection of a burst
  35. GRB 240222A: Swift-BAT refined analysis
  36. GRB 240222A: Swift-XRT refined Analysis
  37. GRB 240222A: Fermi GBM Observation
  38. GRB 240222A: Swift/UVOT Upper Limits
  39. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  40. Swift GRB 240222A: Global MASTER-Net observations report
  41. Fermi GRB 240222A: Global MASTER-Net observations report
  42. EPW20240219aa is Likely a GRB Event
  43. GRB 240222A: REM optical and NIR early-time observations
  44. GRB 240222A: Swift detection of a burst
  45. GRB 240222A: Fermi GBM Final Real-time Localization
  46. GRB 240218A: MeerLICHT upper limits
  47. GRB 240216A: Glowbug gamma-ray detection
  48. GRB 240215B: Fermi GBM Observation
  49. GRB 240218A: LBT H-band detection
  50. GRB 240218A: Swift-BAT refined analysis
  51. Fermi GRB 240220A: Global MASTER-Net observations report
  52. GRB 240220A: Fermi GBM Final Real-time Localization
  53. Konus-Wind detection of GRB 240218A
  54. GRB 240218A: Swift-XRT refined Analysis
  55. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  56. GRB 240218A: Fermi GBM Detection
  57. GRB 240215A: Fermi GBM Observation
  58. GRB 240216A: GRBAlpha detection
  59. GRB 240215B: GRBAlpha detection
  60. IPN triangulation of GRB 240209A
  61. GRB 240218A: VLT/FORS2 z-band detection
  62. GRB 240218A: Enhanced Swift-XRT position
  63. GRB 240218A: REM detection of a NIR afterglow candidate
  64. GRB 240213A: GRBAlpha detection
  65. GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
  66. GRB240218A: VLT/X-shooter upper limits
  67. GRB 240218A: Swift detection of a burst
  68. GRB 240215C: Fermi GBM Final Real-time Localization
  69. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  70. Fermi GRB 240216A: Global MASTER-Net observations report
  71. GRB 240216A: Fermi GBM Final Real-time Localization
  72. GRB 240215A: Tiled Swift observations
  73. GRB 240215A: Swift/BAT-GUANO localization of a burst
  74. GRB 240209A: Classification of AT2024cew/GOTO24pw as Type Ia-pec supernova
  75. GRB 240209A: Fermi GBM observation
  76. GRB 240213A: Glowbug gamma-ray detection
  77. GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
  78. GRB 240209A: Wendelstein Optical Observations
  79. GRB 240128A: Further Swift-XRT observations
  80. GRB 240214A: Tiled Swift observations
  81. GRB 240214A/1H 0451-560: MAXI/GSC detection
  82. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  83. Fermi GRB 240213A: Global MASTER-Net observations report
  84. GRB 240213A: Fermi GBM Final Real-time Localization
  85. GRB 240209A: NOEMA non-detection of AT2024cew / GOTO24pw counterpart candidate
  86. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  87. GRB 240209A: GOTO optical counterpart candidate
  88. Konus-Wind detection of GRB 240204A
  89. Konus-Wind detection of GRB 240205A (short)
  90. GRB 240209A: Fermi GBM Final Localization
  91. Fermi trigger No 729152364: Global MASTER-Net observations report
  92. IPN triangulation of GRB 240205A (short)
  93. GRB 240205B: PRIME near infrared detection
  94. GRB 240205A (short): Glowbug gamma-ray detection
  95. GRB240204A: Swift/UVOT Upper Limits
  96. GRB 240205B: AstroSat CZTI detection
  97. GRB 240205B: Swift-BAT refined analysis
  98. Konus-Wind detection of GRB 240205B (long / very soft)
  99. GRB 240207A: Fermi GBM Final Real-time Localization
  100. Konus-Wind detection of GRB 240125A

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