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"

27026 results found.

  1. GRB 090926A: Fermi LAT and GBM refined analysis
  2. GRB 090929B: Skynet/DSO Observations
  3. GRB 090929B: Swift/UVOT Observations
  4. Konus-RF observation of GRB 090929A
  5. GRB 090929B: RAPTOR Discovery of Optical Counterpart
  6. GRB 090929A BAT location of the Fermi GBM burst
  7. GRB 090929B: Swift detection of a burst
  8. GRB 090929A: Fermi GBM detection
  9. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  10. Konus-Wind and Konus-RF observations of GRB 090926A
  11. GRB 090926B: Fermi GBM detection
  12. GRB 090927: Zadko Telescope observations
  13. GRB 090927, Swift-BAT refined analysis of the possibly short burst
  14. Swift/UVOT observations of GRB 090927
  15. GRB 090926A: Skynet/PROMPT Continued Observations
  16. GRB 090927: Swift XRT refined analysis
  17. GRB 090926A: Suzaku WAM observation of the prompt emission
  18. GRB090926B: Swift/UVOT Upper Limits
  19. GRB090926A: Swift/UVOT observations
  20. GRB 090927: Swift/UVOT detection of an optical afterglow
  21. GRB 090927: Swift detection of a short burst
  22. GRB 090926B: MAXI GSC detection
  23. GRB 090926B: Swift XRT refined analysis
  24. GRB 090926B: Swift-BAT refined analysis
  25. GRB 090926A: Swift/UVOT detection of an optical afterglow
  26. GRB 090926A: Skynet/PROMPT Discovery of the Optical Afterglow
  27. GRB 090926B: Swift detection of a burst
  28. GRB 090926: Fermi LAT detection
  29. GRB 090926: Fermi GBM detection
  30. GRB 090925: Fermi GBM detection
  31. GRB 090922A: Fermi GBM detection
  32. GRB 090715B: Skynet/PROMPT Detections
  33. GRB 090726: Skynet/GORT Observations
  34. GRB 090916: Swift-XRT upper limit
  35. GRB 090807: Skynet/DSO Observations
  36. Short-Duration GRB 090916: Skynet/PROMPT Observations
  37. GRB 090915: SARA detection of afterglow candidate
  38. GRB 090915: Swift/UVOT detection of an optical afterglow candidate
  39. GRB 090702: Skynet/GORT Observations
  40. GRB 090902B: Skynet/PROMPT Observations
  41. GRB 090916, Swift-BAT refined analysis
  42. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  43. GRB 090916: Swift detection of a short burst
  44. GRB 090915 Swift-BAT detection of a burst in ground analysis
  45. GRB 090827: Confirmation of the X-ray afterglow
  46. GRB 090912: Swift-XRT refined analysis
  47. GRB 090912, Swift-BAT refined analysis
  48. GRB 090912: Swift/UVOT Upper Limits
  49. GRB 090912: Swift detection of a burst
  50. GRB 090910: Fermi GBM detection
  51. GRB 090814A: Skynet/DSO & GORT Observations
  52. GRB 090904B: GROND detection of the optical afterglow
  53. GRB 090831A: Suzaku WAM observation of the prompt emission
  54. GRB 090904A: Swift/UVOT Refined Analysis
  55. GRB 090904B: Swift/UVOT Refined Analysis
  56. GRB 090902B: Suzaku WAM observation of the prompt emission
  57. GRB 090829A: Suzaku WAM observation of the prompt emission
  58. GRB 090904B: Fermi GBM detection
  59. GRB 090904A: Swift-XRT refined analysis
  60. GRB 090904B: Swift XRT Refined Analysis
  61. GRB 090904B: Swift-BAT refined analysis
  62. GRB 090904A: Swift-BAT refined analysis
  63. GRB090904B: REM observations
  64. GRB 090904B: Swift detection of a burst
  65. GRB 090904A: ROTSE-III Optical Limits
  66. GRB 090904: Swift detection of a burst
  67. GRB 090902B: ROTSE-III Detection of Optical Afterglow
  68. GRB 090902B: Swift/UVOT refined analysis
  69. GRB090902B: Swift XRT refined analysis
  70. GRB 090902B: GROND NIR Afterglow Observations
  71. GRB 090902B: Fermi LAT and GBM refined analysis.
  72. GRB090902B: Swift/UVOT observations
  73. GRB 090902B: Fermi LAT detection
  74. GRB 090902B: Fermi GBM detection of a bright burst
  75. GRB 090902: Fermi GBM detection
  76. GRB 090831A: IPN Triangulation
  77. GRB 090831C BAT refined analysis
  78. GRB 090831C: GROND upper limits
  79. Swift Trigger 361477, called GRB090831B, is probably not real.
  80. GRB090831C: Swift/UVOT upper limits
  81. GRB 090831C: Swift XRT Refined Analysis
  82. GRB 090829B: Fermi GBM Detection
  83. GRB 090831C: Swift detection of a burst
  84. GRB 090831B, RIMOTS optical upper limits
  85. GRB 090831: MAXI GSC detection
  86. GRB 090831B: Swift detection of a possible burst
  87. GRB 090831: Fermi GBM detection
  88. GRB090829: Fermi GBM Detection
  89. GRB 090827: Swift XRT and UVOT observations
  90. GRB 090827 Burst discovered in BAT ground analysis
  91. GRB 090826: Fermi GBM detection
  92. GRB 090828: Fermi GBM detection
  93. Fermi Gamma-ray Burst Monitor trigger 273123112 is not a GRB
  94. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  95. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  96. GRB 090820: detection of a strong burst by RT-2 on board CORONAS PHOTON
  97. GRB 090820B: Fermi GBM detection
  98. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  99. GRB 090820: Fermi GBM Detection of a bright burst.
  100. GRB 090815C: Swift refined analysis

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov