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"

23724 results found.

  1. GRB 240303B: VZLUSAT-2 detection
  2. GRB 240229A: VZLUSAT-2 detection
  3. Improved IPN triangulation of GRB 240227A (short)
  4. IPN triangulation of GRB 240229A
  5. GRB240218A: ATCA observation of the radio counterpart
  6. Transient EPW20240219aa: Optical observations with LDT
  7. Konus-Wind detection of GRB 240303B
  8. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  9. IPN triangulation of GRB 240303B
  10. Swift J151857.0-572147: Swift-BAT refined analysis
  11. Swift detection of Swift J151857.0-572147
  12. GRB 240303B: CALET Gamma-Ray Burst Monitor detection
  13. Fermi trigger No 731161136: Global MASTER-Net observations report
  14. Swift GRB 240303A: Global MASTER-Net observations report
  15. GRB 240215A: Swift-XRT afterglow detection
  16. GRB 240303A: Swift detection of a burst
  17. GRB 240225B: Glowbug gamma-ray detection
  18. GRB 240225C: Glowbug gamma-ray detection
  19. GRB 240225A (short): Glowbug gamma-ray detection
  20. GRB 240229A: DDOTI Upper Limits on the Afterglow
  21. GRB 240218A: NOEMA upper limit
  22. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  23. Fermi GRB 240229A: Global MASTER-Net observations report
  24. IceCube Alert 240229.66: Global MASTER-Net observations report
  25. Konus-Wind detection of GRB 240225B (long)
  26. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  27. GRB 240225B: WINTER near-IR observations and upper limits
  28. GRB 240226A: GRBAlpha detection
  29. Fermi GRB 240227A: Global MASTER-Net observations report
  30. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  31. IPN triangulation of GRB 240227A (short)
  32. Fermi GRB 240226A: Global MASTER-Net observations report
  33. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  34. Transient EPW20240219aa: Kp-band imaging observations with NIRES
  35. Transient EPW20240219aa: J-band upper limits from WINTER
  36. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  37. GRB 240225B: GOTO detection of a candidate optical afterglow
  38. Transient EPW20240219aa: REM optical/NIR upper limits
  39. GRB 240225C: GRBAlpha detection
  40. Fermi trigger No 730618809: Global MASTER-Net observations report
  41. GRB 240225B: AstroSat CZTI detection
  42. GRB 240225B: MAXI/GSC detection
  43. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  44. GRB 240222A: GRBAlpha detection
  45. Transient EPW20240219aa: GECKO: LOAO Optical Upper Limits
  46. VLA X-band observation of EPW20240219aa
  47. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  48. GRB 240222A: Swift-BAT refined analysis
  49. Swift GRB 240222A: Global MASTER-Net observations report
  50. Fermi GRB 240222A: Global MASTER-Net observations report
  51. GRB 240222A: REM optical and NIR early-time observations
  52. Swift GRB240221.92: Global MASTER-Net observations report
  53. GRB 240216A: Glowbug gamma-ray detection
  54. GRB 240218A: Swift-BAT refined analysis
  55. Fermi GRB 240220A: Global MASTER-Net observations report
  56. Konus-Wind detection of GRB 240218A
  57. GRB 240218A: Swift-XRT refined Analysis
  58. GRB 240216A: GRBAlpha detection
  59. GRB 240215B: GRBAlpha detection
  60. IPN triangulation of GRB 240209A
  61. Fermi trigger No 729914426: Global MASTER-Net observations report
  62. GRB 240218A: REM detection of a NIR afterglow candidate
  63. GRB 240213A: GRBAlpha detection
  64. GRB 240218A: Swift detection of a burst
  65. Swift GRB240218.08: Global MASTER-Net observations report
  66. Fermi GRB 240216A: Global MASTER-Net observations report
  67. Fermi trigger No 729719508: Global MASTER-Net observations report
  68. Fermi trigger No 729703985: Global MASTER-Net observations report
  69. Fermi trigger No 729650855: Global MASTER-Net observations report
  70. GRB 240209A: Classification of AT2024cew/GOTO24pw as Type Ia-pec supernova
  71. GRB 240213A: Glowbug gamma-ray detection
  72. The AGILE satellite ceased operations and re-entered today into the atmosphere
  73. The AGILE satellite ceased operations and re-entered today into the atmosphere
  74. GRB 240209A: Wendelstein Optical Observations
  75. GRB 240214A/1H 0451-560: MAXI/GSC detection
  76. Fermi GRB 240213A: Global MASTER-Net observations report
  77. GRB 240209A: NOEMA non-detection of AT2024cew / GOTO24pw counterpart candidate
  78. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  79. GRB 240209A: GOTO optical counterpart candidate
  80. Konus-Wind detection of GRB 240204A
  81. Konus-Wind detection of GRB 240205A (short)
  82. Fermi trigger No 729152364: Global MASTER-Net observations report
  83. IPN triangulation of GRB 240205A (short)
  84. GRB 240205A (short): Glowbug gamma-ray detection
  85. Swift Trigger 1213872 is not an astrophysical event
  86. GRB240204A: Swift/UVOT Upper Limits
  87. GRB 240205B: AstroSat CZTI detection
  88. Fermi trigger No 729012023: Global MASTER-Net observations report
  89. GRB 240205B: Swift-BAT refined analysis
  90. Konus-Wind detection of GRB 240205B (long / very soft)
  91. Konus-Wind detection of GRB 240125A
  92. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  93. GRB 240205B: BOOTES-6 optical afterglow follow-up
  94. GRB 240205B: REM detection of the optical/NIR afterglow
  95. GRB 240205B: Fermi GBM Observation
  96. GRB 240204A: AstroSat CZTI detection
  97. GRB 240204A : OHP/T193/T120 optical afterglow fading detection
  98. GRB 240204A: Swift-BAT refined analysis
  99. GRB 240205B: BOOTES-7 optical afterglow follow-up
  100. Fermi trigger No 728749569: 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