Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

19875 results found.

  1. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  2. Swift XRT boresight
  3. GRB 060927: Swift detection of a burst
  4. GRB060926: VLT redshift
  5. GRB 060926: Swift-UVOT Detections
  6. GRB 060926: Swift XRT refined analysis
  7. GRB 060926, Swift-BAT refined analysis
  8. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  9. GRB 060926: BOOTES-IR observations
  10. GRB060926 OPTIMA-Burst optical observation
  11. GRB 060926: Swift detection of a burst
  12. GRB 060923C, Swift-BAT refined analysis
  13. GRB 060923C: VLA Observation
  14. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  15. GRB060923B: Swift/UVOT upper limits
  16. GRB 060923B: Swift XRT Refined Analysis
  17. GRB 060923C: Swift XRT refined analysis
  18. GRB 060923C, Swift-BAT partial refined analysis
  19. GRB 060923A: Swift XRT refined analysis
  20. GRB 060923A: Keck and Gemini Observations
  21. GRB 060923B, Swift-BAT refined analysis
  22. GRB060923C : Faulkes Telescope South optical limits
  23. GRB060923C: Faulkes Telescope North optical observations
  24. GRB 060923C: Swift detection of a burst
  25. GRB 060923B: Swift detection of a burst
  26. GRB 060923, Swift-BAT refined analysis
  27. GRB 060923: Early Super-LOTIS Observations
  28. GRB060923: Faulkes Telescope North optical observations
  29. GRB 060923: KAIT observations
  30. GRB 060923: Swift detection of a burst
  31. Swift detection of IGR J17497-2821 (trigger 230504)
  32. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  33. GRB060919: Swift/UVOT optical observations
  34. GRB 060919, Swift-BAT refined analysis
  35. GRB060919: XRT refined analysis
  36. GRB 060919: TAROT optical observations
  37. GRB 060919: Swift detection of a burst
  38. GRB 060912A: VLA Observation
  39. GRB060825: MAGIC telescope GeV observation
  40. Konus-Wind observation of GRB 060912
  41. GRB060912: Swift/UVOT Observations
  42. GRB060912: OPTIMA-Burst optical observations
  43. GRB 060912: Swift XRT Team Refined Analysis
  44. GRB 060912, Swift-BAT refined analysis
  45. GRB 060912: Swift detection of a burst with an optical afterglow
  46. VLA observations of GRB 060908
  47. GRB 060908, Swift/XRT refined analysis
  48. GRB 060908: Swift/UVOT Observations
  49. GRB 060908, Swift-BAT refined analysis
  50. GRB 060908 - SDSS Pre-burst Observations
  51. GRB 060908: Swift detection of a burst with a bright optical counterpart
  52. GRB 060904A: Suzaku/WAM observation of the prompt emission
  53. GRB060904b optical detections (delayed report due to internet outage)
  54. GRB 060906: Early RAPTOR optical limits
  55. GRB 060906, Swift-BAT refined spectral analysis
  56. GRB 060906: Swift/XRT Refined Analysis
  57. GRB 060906: Swift-UVOT observations
  58. VLT redshift of GRB 060906
  59. GRB 060906, Swift-BAT refined analysis
  60. GRB 060906: KAIT observations
  61. GRB 060906 (?): P60 Optical Afterglow Candidate
  62. GRB 060906: Swift detection of a probable burst
  63. GRB 060904A Milagro GeV/TeV Observations
  64. GRB060904A: Swift/UVOT optical observations
  65. GRB 060904A: pseudo-z from spectral parameters of the prompt emission
  66. GRB 060904B: Swift-BAT refined analysis
  67. GRB060904b: Optical observations with Swift/UVOT
  68. Konus-Wind observation of GRB 060904A
  69. GRB 060904B: Swift-XRT refined analysis
  70. GRB 060904A: Refined analysis of the Swift-BAT burst
  71. GRB 060904A: Swift-XRT refined analysis
  72. GRB 060904A: Suzaku-XIS and -HXD observation plan
  73. GRB 060904B: Optical observations at Crni Vrh
  74. GRB060904B: Watcher observations
  75. GRB 060904B BOOTES-IR and 1.5m OSN observations
  76. GRB 060904B: TAROT optical counterpart observations
  77. GRB060904B - SDSS Pre-Burst Observations
  78. GRB 060904: TAROT optical observations
  79. GRB 060904B: Swift detection of a burst with optical counterpart
  80. GRB 060904B: ROTSE-III Detection of Optical Counterpart
  81. GRB060904 - SDSS Pre-Burst Observations
  82. GRB 060904: Swift detection of a bright burst
  83. 060901: Swift UVOT followup observations
  84. GRB 060901: Swift/XRT Refined Analysis
  85. GRB 060901: Swift/XRT Position
  86. Two bright bursts from SGR 1806-20 detected with IBAS
  87. GRB 060604: VLA Observation
  88. GRB 060814: Suzaku/WAM observation of the prompt emission
  89. GRB 060605: VLA Observation
  90. GRB 060707: VLA observation
  91. GRB 060825: VLA observations
  92. GRB 060825: pseudo-z from spectral parameters of the prompt emission
  93. Swift-BAT trigger 226614 is not a GRB
  94. GRB060826 - SDSS Pre-Burst Observations
  95. GRB 060826(?): Swift detection of a possible burst
  96. GRB 060825: XRT Team Refined Analysis
  97. GRB 060825: Swift-BAT Refined Analysis
  98. GRB 060813: Swift/BAT, Konus-Wind, and Suzaku/WAM joint prompt spectral analysis
  99. GRB060825: Liverpool Telescope optical observations
  100. GRB 060825: TAROT optical observations

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