Skip to main content
New! Browse Circulars by Event, Advanced Search, Sample Codes, Schema Release. 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"

18675 results found.

  1. GRB 071018, Swift-BAT refined analysis
  2. GRB 071018?: Swift detection of a possible burst
  3. GRB 071010B: Suzaku WAM observation of the prompt emission
  4. GRB 071013: 3rd TLS Epoch - constraints on variability
  5. GRB 071013: TLS Upper Limit
  6. VLA detection of radio afterglow of GRB 071010B
  7. VLA non-detection of GRB 071011
  8. GRB 071013: Optical observations
  9. GRB 071013, Swift-BAT refined analysis
  10. GRB 071013: Swift detection of a burst
  11. GRB 071010C Swift-BAT detection of a burst
  12. GRB 071011: Swift-XRT refined analysis
  13. VLA non-detection of GRB 071010A
  14. GRB 071011, Optical afterglow
  15. GRB 071011: MARGE Optical Limits
  16. GRB 071011: XRT afterglow detection
  17. GRB 071011, Swift-BAT refined analysis
  18. GRB 071011: Early Super-LOTIS Observations
  19. GRB 071010B: Bright OT confirmed with TLS
  20. GRB 071011: Swift detection of a burst
  21. Optical Observation: GRB 071010
  22. Optical observations: GRB 071010A
  23. Konus-Wind observation of GRB 071010B
  24. GRB071010B: Swift/XRT detection
  25. GRB 071010B, Swift-BAT refined analysis
  26. GRB 071006, Swift-BAT refined analysis
  27. GRB 071010B: Swift detection of a burst
  28. GRB 071010: Swift-XRT observation
  29. GRB 071008, Swift-BAT refined analysis
  30. GRB 071010, Swift-BAT refined analysis
  31. GRB071008: Swift-XRT observation
  32. GRB 071010: TAROT La Silla observatory detection of the afterglow
  33. GRB 071010: Swift detection of a burst
  34. GRB 071006 Swift-BAT detection of a burst
  35. GRB071008: IAC80 observation
  36. GRB 071008: Swift detection of a burst
  37. GRB 071003: XRT refined analysis
  38. GRB070920A: MAGIC telescope GeV observation
  39. Radio detection of GRB 071003 with the VLA
  40. GRB 070810B: further XRT analysis
  41. Konus-Wind observation of GRB 071003
  42. GRB 071003: Swift XRT position
  43. GRB 071003, Swift-BAT refined analysis
  44. GRB 071003: MARGE Observations
  45. GRB 071003 Optical observations
  46. GRB 071003: KAIT optical afterglow observations
  47. GRB 071003: Swift detection of a bright burst
  48. GRB 070714B: host galaxy spectroscopic redshift
  49. GRB 071001: Swift-XRT Team refined analysis
  50. GRB 071001, Swift-BAT refined analysis
  51. Faulkes Telescope South observations of GRB 071001
  52. GRB 071001: Swift detection of a burst
  53. VLA observation of GRB 070923
  54. Disregard the Swift-XRT Notices today
  55. GRB070925: Swift-XRT Afterglow confirmation
  56. GRB070925: Swift-XRT Position
  57. Update on Swift Status
  58. GRB 070920B: ROTSE-III Early Optical Limits
  59. Recent SGR1806-20 Activity
  60. GRB 070923, Swift-BAT refined analysis
  61. GRB 070920B: XRT observations
  62. GRB 070923: Swift detection of a short hard burst
  63. GRB 070917: Suzaku/WAM observation of the prompt emission
  64. GRB 070920B: TAROT La Silla observatory optical observations
  65. GRB 070917: Confirmation of the X-ray afterglow
  66. GRB 070920B, Swift-BAT refined analysis
  67. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  68. GRB 070920B: NOT optical observations
  69. GRB 070920B: Swift detection of a burst
  70. GRB 070920, Swift-BAT refined analysis
  71. GRB 070920: TAROT Calern observatory optical observations
  72. GRB 070920: Swift detection of a burst
  73. SGR1806-20: Swift-BAT detection of enhanced activity
  74. GRB 070917: pseudo-z= 2.40 from prompt emission spectrum
  75. Konus-Wind observation of GRB 070917
  76. Swift Status and XRT Calibration Uncertainties
  77. GRB 070917: Swift-XRT observations
  78. GRB 070917: KAIT optical limits
  79. GRB 070917: R band observations
  80. GRB 070917, Swift-BAT refined analysis
  81. GRB 070917: Swift detection of a bright burst
  82. GRB 070911: Suzaku WAM observation of the prompt emission
  83. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  84. GRB 070809: The Swift evidence for the SHB nature of this burst
  85. GRB 070913: Swift-BAT refined analysis
  86. GRB 070913: Corrected BAT position
  87. GRB 070913: TAROT La Silla observatory optical observations
  88. GRB 070913: Swift detection of a burst
  89. Swift-BAT Notices back to autonomous real-time distribution
  90. GRB 070911: Swift XRT refined analysis
  91. GRB 070911, Swift-BAT refined analysis
  92. GRB 070911: Swift detection of a burst
  93. IPN search for a GRB associated with TAROT transient on August 31
  94. Intense burst from SGR 1806-20 detected on September 7
  95. GRB 070824 - Combined SuperAGILE/IPN Localization
  96. GRB 070731: Swift/UVOT Upper Limit
  97. GRB 070805: UVOT afterglow candidate retraction
  98. GRB070810b: optical candidate
  99. GRB 070810A: ROTSE-III Refined Analysis
  100. Swift observatory off line

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