Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to https://gcn.nasa.gov.
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"
  1. GRB101114A: Swift/UVOT Upper Limits
  2. GRB 101114A: Confirmation of the X-ray afterglow
  3. GRB 101117B: Swift-BAT refined analysis
  4. GRB 101117B: Enhanced Swift-XRT position
  5. GRB 101117B: Swift/UVOT Discovery of an Optical Afterglow
  6. GRB 101117B: Swift detection of a burst
  7. XRF101117A: MAXI/GSC detection of a short X-ray transient
  8. GRB 101114A: GROND Upper limits
  9. Konus-Wind observation of GRB 101114A
  10. Fermi GBM detection of a burst from a galactic source
  11. GRB 101114A: Swift-XRT candidate afterglow detection and analysis
  12. GRB 101114A, Swift-BAT GRB detected by ground processing
  13. Possible detection of INTEGRAL burst GRB 101112A by the EVLA
  14. GRB 101112A: Fermi GBM detection
  15. GRB 101112A: optical observations
  16. GRB 10112A: MASTER optical observations
  17. Konus-Wind observation of GRB 101112A
  18. GRB 101112A - XRT source detection/analysis
  19. GRB 101112A: BOOTES-2/TELMA optical afterglow candidate
  20. GRB101112A: Liverpool Telescope Afterglow Candidate
  21. GRB 101112A: a long GRB detected by INTEGRAL
  22. GRB 100906A: optical observations
  23. GRB 090113, the review of the sky area in plate archives
  24. GRB 101030A : MOA optical observation
  25. GRB 101030A: GROND optical/NIR afterglow candidate
  26. GRB 101030A : Swift XRT refined analysis
  27. GRB 101030A: Swift/UVOT Upper Limits
  28. GRB 101030A: Swift-BAT refined analysis
  29. GRB 101030A: Enhanced Swift-XRT position
  30. GRB 101030A: Swift detection of a burst
  31. GRB 090111, the review of the sky area in plate archives (1976-1996)
  32. Konus-Wind observation of GRB 101023A
  33. GRB 101024A: GROND optical/NIR observations
  34. GRB 101024A: Zadko observatory - Gingin. Optical observations refined analysis
  35. GRB 101024A: Swift XRT refined analysis
  36. GRB 101024A: Zadko observatory - Gingin. Optical observations
  37. GRB 101023A: miniTAO/ANIR NIR detection
  38. GRB 101024A: Fermi GBM observation
  39. GRB 101023A: Fermi GBM observation
  40. GRB101024A: Swift/UVOT
  41. GRB 101024A: Swift-BAT refined analysis
  42. GRB 101024A: GRAS06 optical observations
  43. GRB 101024A: Enhanced Swift-XRT position
  44. Swift/UVOT observations of GRB101023A
  45. GRB 101024A: Swift detection of a burst with an optical afterglow
  46. GGRB 101023A: GROND detection of the optical-NIR afterglow
  47. GRB 101023A: Swift-XRT Team Refined Analysis
  48. GRB 101023A: Swift-BAT refined analysis
  49. GRB 101023A: Gemini discovery of optical afterglow
  50. GRB 101023A: Enhanced Swift-XRT position
  51. GRB 101023A: REM NIR observations
  52. GRB 101023A: Swift detection of a burst
  53. GRB 101011A: miniTAO/ANIR NIR upper limits
  54. GRB 101020A: MASTER prompt and afterglow limit
  55. GRB 101020A: BOOTES2 follow-up and limit
  56. GRB 101020A: MASTER polarization optical observations
  57. GRB 101020A, Swift-BAT refined analysis
  58. GRB 101020A: Swift detection of a burst
  59. GRB 101017A: miniTAO/ANIR NIR upper limits
  60. GRB 101017A: Swift XRT refined analysis
  61. GRB 101017A: Swift/UVOT Observations
  62. GRB 101008A: correction to the GCN 11352
  63. GRB 101008A: optical observations
  64. GRB101017A: MITSuME Okayama optical upper limits
  65. Konus-Wind observation of GRB 101017A
  66. GRB 101014A: Fermi LAT detection
  67. GRB 101017A: Enhanced Swift-XRT position
  68. GRB 101017A: Swift-BAT refined analysis
  69. GRB 101017A: ROTSE-III Optical Limits
  70. GRB 101017A: Swift detection of a burst with optical counterpart
  71. GRB 101011A: Fermi GBM detection
  72. GRB 101011A: BOOTES-3 Upper Limit
  73. Konus-Wind observation of GRB 101014A
  74. GRB 101014A: Fermi GBM detection
  75. GRB 100906A: D50 optical detection
  76. GRB 100902A: D50 optical limit
  77. GRB 101011A: Swift/UVOT observations
  78. GRB 101011A, GROND upper limits
  79. GRB 101011A: Zadko observatory - Gingin optical observations
  80. GRB 101011A: XRT Refined Analysis
  81. GRB 101011A: Swift/UVOT Observations of a Possible Optical Afterglow
  82. GRB 101011A: Enhanced Swift-XRT position
  83. GRB 101011A: Swift-BAT refined analysis
  84. GRB 101011A: Swift detection of a burst
  85. GRB 101008A: Fermi GBM observation
  86. GRB 101008A: MASTER prompt optical observations (correction to GCN#11328)
  87. GRB 101008A: MASTER prompt optical observations
  88. GRB 101008A: Swift-BAT refined analysis
  89. GRB101008A, GROND detection of a fading afterglow
  90. GRB 101008A: Swift-XRT refined analysis
  91. GRB 101008A: SAO RAS optical observations
  92. GRB 100915 optical upper limit
  93. Subject: GRB 101008: Swift/UVOT Upper Limits
  94. GRB 101008A: Enhanced Swift-XRT position
  95. GRB 101008A: 1.23m CAHA optical observations
  96. GRB 101008A: Swift/XRT Detection of an Afterglow with no UVOT Counterpart
  97. GRB 101008A: Swift detection of a burst
  98. GRB 100728B: X-shooter redshift
  99. Refined analysis shows Swift Trigger 435520 is not a GRB
  100. Swift Trigger 435520 is probably not a GRB

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