Skip to main content
Retirement of GCN Classic VOEvent Brokers. 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. GRB080503 XRT refined analysis
  2. GRB 080503, Swift-BAT refined analysis
  3. GRB 080430
  4. GRB 080430
  5. GRB 080430
  6. GRB 080503: Enhanced Swift-XRT position
  7. GRB 080503: MITSuME Akeno optical upper limits
  8. GRB 080503: New candidate afterglow/host in Gemini imaging
  9. GRB 080503: Optical afterglow candidate and LRIS spectroscopy of the short burst
  10. GRB 080503: Swift detection of a short burst
  11. GRB 080411: Continued Swift Monitoring
  12. GRB 080430: Optical observations
  13. GRB 080430: Shallow decay
  14. GRB080430: RTT150 Optical Observations
  15. GRB080430: Swift/UVOT observations
  16. VLA radio upper limit on GRB 080430
  17. GRB 080430 - multicolor observations of the afterglow
  18. GRB 080430 optical observations
  19. GRB 080430, Swift-BAT refined analysis
  20. GRB080430: optical observations
  21. GRB 080430: Hobby-Eberly Telescope Absorption Redshift
  22. GRB 080430: Swift-XRT refined analysis
  23. GRB 080430: Enhanced Swift-XRT position
  24. GRB080430: Optical observation in AsU CAS Ondrejov & Brno
  25. GRB 080430: Spectroscopy from CAHA
  26. GRB 080430 - SDSS Pre-Burst Observations
  27. GRB 080430: Bootes observation
  28. GRB 080430: Swift detection of a burst with optical afterglow
  29. GRB 080430: TAROT Calern observatory optical observations
  30. GRB960202B - on the association with SN 1996cr
  31. GRB080426: Observations from CAHA
  32. GRB 080426: Swift-XRT refined analysis
  33. GRB080426: Swift/UVOT upper limits
  34. GRB 080426: Enhanced Swift-XRT position
  35. GRB 080426, Swift-BAT refined analysis
  36. GRB 080426: Swift detection of a possibly short burst
  37. Possible GRB 080315: XRT non-detection of afterglow
  38. GRB 080320 : Faulkes Telescope North Observations
  39. GRB 080319A : Liverpool and Faulkes Telescopes Observations
  40. GRB080319A: MAGIC telescope GeV observation
  41. Swift-BAT trigger 309665 is not a GRB
  42. GRB 080420A: ROTSE-III Optical Limits on a possible short burst
  43. GRB 080420?: Swift detection of a possible short burst
  44. GRB080310, BVRcIc field calibration
  45. GRB 080413A: Suzaku/WAM and Swift/BAT joint spectral analysis
  46. GRB 080413B: Rapid PROMPT Observations
  47. Swift XRT and UVOT observations of GRB080414
  48. GRB 080319B: Jet Break, Energetics, Supernova
  49. GRB 080413B: Faulkes Telescope South optical afterglow observations
  50. GRB 080413A: Liverpool Telescope and Faulkes Telescope South optical observations
  51. GRB 080413A: Suzaku WAM observation of the prompt emission
  52. GRB 080413B: Suzaku WAM observation of the prompt emission
  53. GRB 080413A: MOA-II optical afterglow observations
  54. GRB 080319B: Continued Gemini-N monitoring
  55. GRB 080414: RTT150 optical observations
  56. GRB 080414 Watcher observations
  57. GRB 080414: A long GRB detected by INTEGRAL
  58. VLA radio observations of GRB 080413B
  59. GRB 080413A: Gemini-South Spectroscopy
  60. GRB 080413B: Gemini-South Spectroscopy
  61. VLA radio observations of GRB 080413A
  62. IBAS Alert n. 5257 : not a GRB
  63. GRB 080413B: Ep,i-Eiso correlation
  64. GRB080413B
  65. Swift-BAT spectral lag analysis of GRB 080413B
  66. GRB 080413a, SMARTS optical/IR afterglow observations
  67. GRB 080413B: Swift XRT refined analysis
  68. GRB080413A: Swift/UVOT observations
  69. GRB 080413B, Swift-BAT refined analysis
  70. GRB 080413A: Swift-XRT refined analysis
  71. GRB 080413A, Swift-BAT refined analysis
  72. GRB 080413A Bootes observation
  73. GRB 080413A: VLT/UVES redshift
  74. GRB 080413B: VLT redshift
  75. GRB080413B: REM NIR & Optical Observation
  76. GRB 080413B: GROND detection of afterglow in all bands
  77. GRB 080413B: Swift detection of a possibly short burst with optical counterpart
  78. GRB 080413A: REM detection of the NIR Afterglow
  79. GRB 080413: Enhanced Swift-XRT position
  80. GRB 080413: TAROT Calern observatory optical observations
  81. GRB 080413: Swift detection of a burst with an optical afterglow
  82. GRB 080413: ROTSE-III Detection of Optical Counterpart
  83. GRB 080411: Swift/UVOT refined analysis
  84. GRB 080411, Swift-BAT refined analysis
  85. GRB 080411: Swift-XRT Refined Analysis
  86. Konus-Wind observation of GRB 080411
  87. GRB 080411: Enhanced Swift-XRT position
  88. GRB 080411: VLT redshift
  89. GRB 080411: GROND detection of optical afterglow candidate
  90. GRB080330: MAGIC telescope GeV observation
  91. GRB 080411: Swift detection of a bright burst
  92. GRB 080330: Swift-XRT refined position retraction
  93. GRB 080409: Swift-BAT refined analysis
  94. GRB 080408: GROND detection of optical/NIR afterglow candidate
  95. GRB 080330 optical observations
  96. Swift/UVOT observations of GRB080409
  97. GRB 080409: Swift XRT refined analysis
  98. UVOT/Swift Observations of GRB080408
  99. GRB 080408: Swift-XRT position of a possible afterglow
  100. GRB 080409: Enhanced Swift-XRT position

Advanced

Download all Circulars as a .tar.gz archive:
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