Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

28057 results found.

  1. GRB 090831C: Swift XRT Refined Analysis
  2. GRB 090829B: Fermi GBM Detection
  3. GRB 090831C: Enhanced Swift-XRT position
  4. GRB 090831C: Swift detection of a burst
  5. GRB 090831B, RIMOTS optical upper limits
  6. GRB 090831: MAXI GSC detection
  7. GRB 090831B: Swift detection of a possible burst
  8. GRB 090831: Fermi GBM detection
  9. GRB090829: Fermi GBM Detection
  10. GRB 090827: Swift XRT and UVOT observations
  11. GRB 090827 Burst discovered in BAT ground analysis
  12. GRB 090826: Fermi GBM detection
  13. GRB 090828: Fermi GBM detection
  14. GRB 090817 - TLS Observations
  15. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  16. GRB 090823 Long burst with IPN triangulation and BAT position
  17. GRB 090820B: Fermi GBM detection
  18. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  19. GRB 090820: MASTER-Net optical polarization observations
  20. GRB 090820: Fermi GBM Detection of a bright burst.
  21. GRB 090817: optical upper limit
  22. GRB 090817: Confirmation of the X-ray afterglow
  23. GRB 090815C: Swift refined analysis
  24. GRB 090817: Fermi GBM observation
  25. GRB 090817: Swift/UVOT Upper Limits
  26. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  27. GRB 090817: Swift-XRT observations
  28. GRB 090814A: optical observations
  29. GRB 090813: Suzaku WAM observation of the prompt emission
  30. GRB 090812: Suzaku WAM observation of the prompt emission
  31. VLA radio non-detection of GRB 090812
  32. GRB 090815B: Fermi GBM detection
  33. GRB 090815: Fermi GBM detection
  34. GRB 090813: CrAO optical obsevations
  35. GRB090814A: NOT optical follow-ups
  36. GRB 090814B: Swift/UVOT Upper Limits
  37. GRB 090814B: Liverpool Telescope Observations
  38. GRB 090814C: Fermi GBM detection
  39. GRB 090814B: Swift-XRT detection of a possible afterglow.
  40. GRB 090814A: Swift/UVOT Observations
  41. GRB 090814A: Swift-XRT Team Refined Analysis
  42. GRB 090814A, RIMOTS optical upper limits
  43. GRB 090814A: Swift-BAT refined analysis
  44. GRB090814A: VLT spectroscopy
  45. GRB 090814: Enhanced Swift-XRT position
  46. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  47. GRB 090814: Swift detection of a burst
  48. GRB 090813: Swift-XRT refined analysis
  49. GRB 090813, Swift-BAT refined analysis
  50. Konus-Wind observations of GRB090813
  51. GRB090813: Swift/UVOT upper limits
  52. GRB 090813: Enhanced Swift-XRT position
  53. GRB 090813: Liverpool Telescope afterglow confirmation
  54. GRB 090813: P60 Optical Afterglow Confirmation
  55. GRB 090813: Swift detection of a burst
  56. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  57. GRB 090812: RAPTOR detections during the burst
  58. GRB 090812: Swift XRT refined analysis
  59. GRB 090812, RIMOTS optical upper limits
  60. GRB 090812 Swift-BAT Refined Analysis
  61. GRB090812: Swift/UVOT observations
  62. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  63. GRB 090812: Enhanced Swift-XRT position
  64. GRB 090812: P60 Confirmation of Optical Afterglow
  65. GRB 090812: Swift detection of a burst with an optical counterpart
  66. GRB 090807B: Fermi GBM detection
  67. GRB 090809: Further NOT optical observations
  68. VLA radio upper limit on GRB 090809
  69. GRB 090621B: MAGIC telescope GeV observation
  70. GRB 090621A: MAGIC telescope GeV observation
  71. GRB 090809: WHT observations
  72. GRB 090809B: Fermi GBM detection
  73. GRB 090809: Swift-XRT refined analysis
  74. GRB090809: Swift/UVOT observations
  75. GRB 090809: Enhanced Swift-XRT position
  76. GRB 090809: Swift-BAT refined analysis
  77. GRB 090809: afterglow confirmation at the NOT
  78. GRB 090809: Swift detection of a burst with a possible optical counterpart
  79. GRB 090807: Liverpool Telescope observations
  80. GRB 090807: MITSuME optical upper limit
  81. GRB 090807: Swift/UVOT Upper Limits
  82. GRB 090807: Swift-XRT refined analysis
  83. GRB 090807, Swift-BAT refined analysis
  84. GRB 090807: Enhanced Swift-XRT position
  85. GRB 090807, RIMOTS optical upper limits
  86. GRB 090807: Swift detection of a burst
  87. GRB 090802B: Fermi GBM detection
  88. GRB 090802: Fermi GBM detection
  89. GRB 090726: optical observation
  90. Swift trigger 358760 is probably a noise event
  91. GRB 090717A: Suzaku WAM observation of the prompt emission
  92. GRB 090709A : Quick look analysis of the Suzaku observation
  93. GRB 090728: Swift-BAT refined analysis
  94. GRB 090727: GRT Optical Observation
  95. GRB 090728: Swift XRT refined analysis
  96. GRB 090726: GRT Optical Observation
  97. GRB 090727: Swift/UVOT Upper Limits
  98. GRB 090728: Swift/UVOT Upper Limits
  99. GRB 090728: Enhanced Swift-XRT position
  100. GRB 090728, RIMOTS optical upper limits

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