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"

19607 results found.

  1. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  2. GRB071021: MARGE Optical Limits
  3. GRB071020, optical upper limit
  4. GRB 071025 Milagro GeV/TeV Observations
  5. Swift UVOT upper limits
  6. GRB 071025: Swift-XRT Team refined analysis
  7. GRB 071025, Swift-BAT refined analysis
  8. GRB 071025: Early Super-LOTIS Observations
  9. GRB 071025: ROTSE-III Refined Analysis
  10. GRB 071025: Swift XRT refined position
  11. GRB 071025: ROTSE-III Detection of Optical Counterpart
  12. GRB 071025: Swift detection of a burst
  13. GRB 071020: BTA spectroscopy
  14. Possible radio detection of GRB 071021 with the VLA
  15. Radio detection of GRB 071020 with the VLA
  16. GRB 071021: optical and NIR observations
  17. GRB 071021, Swift-BAT refined analysis
  18. GRB 071021: Swift-XRT Team refined analysis
  19. Konus-Wind observation of GRB 071020
  20. GRB 071021: Swift detection of a burst
  21. GRB 071020: Swift-XRT refined analysis
  22. GRB 071020, Swift-BAT refined analysis
  23. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  24. GRB071020 - SDSS Pre-burst Observations
  25. GRB 071020: Swift detection of a bright burst
  26. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  27. GRB 071018: Mercator Telescope optical observations
  28. Swift autonomous slewing re-enabled
  29. GRB 071018: Swift-XRT observation
  30. GRB 071017 - Swift XRT observations
  31. VLA radio observation of GRB 071018
  32. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  33. GRB 071018, Swift-BAT refined analysis
  34. GRB 071018?: Swift detection of a possible burst
  35. GRB 071010B: Suzaku WAM observation of the prompt emission
  36. GRB 071013: 3rd TLS Epoch - constraints on variability
  37. GRB 071013: TLS Upper Limit
  38. VLA detection of radio afterglow of GRB 071010B
  39. VLA non-detection of GRB 071011
  40. GRB 071013: Optical observations
  41. GRB 071013, Swift-BAT refined analysis
  42. GRB 071013: Swift detection of a burst
  43. GRB 071010C Swift-BAT detection of a burst
  44. GRB 071011: Swift-XRT refined analysis
  45. VLA non-detection of GRB 071010A
  46. GRB 071011, Optical afterglow
  47. GRB 071011: MARGE Optical Limits
  48. GRB 071011: XRT afterglow detection
  49. GRB 071011, Swift-BAT refined analysis
  50. GRB 071011: Early Super-LOTIS Observations
  51. GRB 071010B: Bright OT confirmed with TLS
  52. GRB 071011: Swift detection of a burst
  53. Optical Observation: GRB 071010
  54. Optical observations: GRB 071010A
  55. Konus-Wind observation of GRB 071010B
  56. GRB071010B: Swift/XRT detection
  57. GRB 071010B, Swift-BAT refined analysis
  58. GRB 071006, Swift-BAT refined analysis
  59. GRB 071010B: Swift detection of a burst
  60. GRB 071010: Swift-XRT observation
  61. GRB 071008, Swift-BAT refined analysis
  62. GRB 071010, Swift-BAT refined analysis
  63. GRB071008: Swift-XRT observation
  64. GRB 071010: TAROT La Silla observatory detection of the afterglow
  65. GRB 071010: Swift detection of a burst
  66. GRB 071006 Swift-BAT detection of a burst
  67. GRB071008: IAC80 observation
  68. GRB 071008: Swift detection of a burst
  69. GRB 071003: XRT refined analysis
  70. GRB070920A: MAGIC telescope GeV observation
  71. Radio detection of GRB 071003 with the VLA
  72. GRB 070810B: further XRT analysis
  73. Konus-Wind observation of GRB 071003
  74. GRB 071003: Swift XRT position
  75. GRB 071003, Swift-BAT refined analysis
  76. GRB 071003: MARGE Observations
  77. GRB 071003 Optical observations
  78. GRB 071003: KAIT optical afterglow observations
  79. GRB 071003: Swift detection of a bright burst
  80. GRB 070714B: host galaxy spectroscopic redshift
  81. GRB 071001: Swift-XRT Team refined analysis
  82. GRB 071001, Swift-BAT refined analysis
  83. Faulkes Telescope South observations of GRB 071001
  84. GRB 071001: Swift detection of a burst
  85. VLA observation of GRB 070923
  86. Disregard the Swift-XRT Notices today
  87. GRB070925: Swift-XRT Afterglow confirmation
  88. GRB070925: Swift-XRT Position
  89. Update on Swift Status
  90. GRB 070920B: ROTSE-III Early Optical Limits
  91. Recent SGR1806-20 Activity
  92. GRB 070923, Swift-BAT refined analysis
  93. GRB 070920B: XRT observations
  94. GRB 070923: Swift detection of a short hard burst
  95. GRB 070917: Suzaku/WAM observation of the prompt emission
  96. GRB 070920B: TAROT La Silla observatory optical observations
  97. GRB 070917: Confirmation of the X-ray afterglow
  98. GRB 070920B, Swift-BAT refined analysis
  99. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  100. GRB 070920B: NOT optical observations

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