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"

21983 results found.

  1. Fermi GRB 240310A: Global MASTER-Net observations report
  2. Swift GRB240309.61: Global MASTER-Net observations report
  3. Fermi trigger No 731571927: Global MASTER-Net observations report
  4. GRB 231215A: further radio observations with the VLA
  5. IceCube Alert 240307.32: Global MASTER-Net observations report
  6. Fermi GRB 240306A: Global MASTER-Net observations report
  7. Fermi GRB 240305A: Global MASTER-Net observations report
  8. GRB 240306A: Swift/BAT-GUANO detection of a burst
  9. Fermi-LAT gamma-ray observations of IceCube-240229A
  10. Swift GRB240305.18: Global MASTER-Net observations report
  11. Swift GRB240305.16: Global MASTER-Net observations report
  12. Fermi GRB 240305C: Global MASTER-Net observations report
  13. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  14. GRB 240218A: ALMA detection
  15. GRB 240218A: Chandra Detection and Jet Break Confirmation
  16. Fermi trigger No 731303574: Global MASTER-Net observations report
  17. GRB240218A: ATCA observation of the radio counterpart
  18. Transient EPW20240219aa: Optical observations with LDT
  19. GRB 240225B: Swift-XRT afterglow detection
  20. Fermi trigger No 731161136: Global MASTER-Net observations report
  21. Swift GRB 240303A: Global MASTER-Net observations report
  22. Swift J151857.0-572147: Confirmation of a new galactic transient
  23. GRB 240215A: Swift-XRT afterglow detection
  24. GRB 240218A: NOEMA upper limit
  25. GRB 240225B: further SAO RAS optical observations
  26. Fermi GRB 240229A: Global MASTER-Net observations report
  27. IceCube Alert 240229.66: Global MASTER-Net observations report
  28. GRB 240225B: Swift ToO observations
  29. GRB 240225B: VLT/X-shooter redshift
  30. GRB 240225B: 3.6m DOT observation
  31. GRB 240225B: WINTER near-IR observations and upper limits
  32. GRB 240225B: SAO RAS optical observations
  33. GRB 240225B: Mondy afterglow observations
  34. Fermi GRB 240227A: Global MASTER-Net observations report
  35. GRB 240225B: Liverpool Telescope afterglow observations
  36. GRB 240225B: Liverpool Telescope optical afterglow observations
  37. GRB 240225B: NOT optical observations
  38. Fermi GRB 240226A: Global MASTER-Net observations report
  39. GRB 240225B: Swift-XRT observations
  40. Transient EPW20240219aa: Kp-band imaging observations with NIRES
  41. Transient EPW20240219aa: J-band upper limits from WINTER
  42. GRB 240225B: GOTO detection of a candidate optical afterglow
  43. Transient EPW20240219aa: REM optical/NIR upper limits
  44. GRB 240222A: ATCA radio observations
  45. Fermi trigger No 730618809: Global MASTER-Net observations report
  46. GRB 240225B: Tiled Swift observations
  47. GRB 240218A: VLA detection
  48. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  49. Transient EPW20240219aa: 7DT Optical Upper Limits
  50. VLA X-band observation of EPW20240219aa
  51. Transient EPW20240219aa: Mondy optical observations
  52. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  53. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  54. GRB 240222A: Swift/UVOT Upper Limits
  55. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  56. Swift GRB 240222A: Global MASTER-Net observations report
  57. Fermi GRB 240222A: Global MASTER-Net observations report
  58. GRB 240222A: REM optical and NIR early-time observations
  59. Swift GRB240221.92: Global MASTER-Net observations report
  60. GRB 240218A: MeerLICHT upper limits
  61. GRB 240218A: LBT H-band detection
  62. Fermi GRB 240220A: Global MASTER-Net observations report
  63. Fermi trigger No 729914426: Global MASTER-Net observations report
  64. GRB 240218A: VLT/FORS2 z-band detection
  65. GRB 240218A: REM detection of a NIR afterglow candidate
  66. Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
  67. Swift GRB240218.08: Global MASTER-Net observations report
  68. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  69. Fermi GRB 240216A: Global MASTER-Net observations report
  70. Fermi trigger No 729719508: Global MASTER-Net observations report
  71. GRB 240215A: Tiled Swift observations
  72. GRB 240215A: Swift/BAT-GUANO localization of a burst
  73. Fermi trigger No 729703985: Global MASTER-Net observations report
  74. Fermi trigger No 729650855: Global MASTER-Net observations report
  75. GRB 240209A: Classification of AT2024cew/GOTO24pw as Type Ia-pec supernova
  76. GRB 240209A: Fermi GBM observation
  77. The AGILE satellite ceased operations and re-entered today into the atmosphere
  78. The AGILE satellite ceased operations and re-entered today into the atmosphere
  79. GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
  80. GRB 240209A: Wendelstein Optical Observations
  81. GRB 240128A: Further Swift-XRT observations
  82. GRB 240214A: Tiled Swift observations
  83. Fermi GRB 240213A: Global MASTER-Net observations report
  84. GRB 240209A: NOEMA non-detection of AT2024cew / GOTO24pw counterpart candidate
  85. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  86. GRB 240209A: GOTO optical counterpart candidate
  87. Fermi trigger No 729152364: Global MASTER-Net observations report
  88. Fermi-LAT gamma-ray observations of IceCube-240204A
  89. GRB 240205B: PRIME near infrared detection
  90. GRB240204A: Swift/UVOT Upper Limits
  91. Fermi trigger No 729012023: Global MASTER-Net observations report
  92. GRB 240205B: VLT/X-shooter redshift
  93. GRB 240205B: BOOTES-6 optical afterglow follow-up
  94. GRB 240205B: ATCA detection of radio counterpart
  95. GRB 240205B: REM detection of the optical/NIR afterglow
  96. GRB 240204A: Mondy optical afterglow observations
  97. GRB 240204A : OHP/T193/T120 optical afterglow fading detection
  98. GRB 240205B: Skynet Optical Afterglow Observations
  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