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"

24923 results found.

  1. GRB 060927 optical limit
  2. GRB 060927, Swift-BAT refined analysis
  3. GRB 060927: Xinglong TNT optical observations
  4. GRB 060927, optical observation
  5. GRB060927 - SDSS Pre-Burst Observations
  6. Swift XRT boresight
  7. GRB060926: VLT redshift
  8. GRB 060926: Swift-UVOT Detections
  9. GRB 060923A: Schedule of Spitzer Space Telescope Observations
  10. GRB 060926, Swift-BAT refined analysis
  11. GRB 060923A: Radio Observations
  12. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  13. GRB 060926: Swift detection of a burst
  14. GRB 060923C, Swift-BAT refined analysis
  15. GRB 060923C: VLA Observation
  16. GRB 060923C: NIR afterglow confirmed
  17. GRB060923C: AROMA optical obsevation
  18. GRB 060923C, optical observation
  19. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  20. GRB 060923C: VLT J-band observations
  21. GRB 060923B: Swift XRT Refined Analysis
  22. GRB 060923A: Swift XRT refined analysis
  23. GRB 060923A: Keck and Gemini Observations
  24. GRB 060923C: Xinglong TNT optical observations
  25. GRB 060923B, Swift-BAT refined analysis
  26. GRB 060923C: Swift detection of a burst
  27. GRB 060923B: Swift detection of a burst
  28. GRB 060923, Swift-BAT refined analysis
  29. GRB 060923: UKIRT nIR observations - candidate afterglow
  30. GRB060923 - SDSS Pre-Burst Observations
  31. GRB 060923: Swift detection of a burst
  32. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  33. GRB 060919 : Faulkes South Telescope 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. GRB 060912A: Probable Host Galaxy
  40. GRB 060912, Swift-BAT refined analysis
  41. GRB 060912: Correction to GCN 5559
  42. GRB 060912: Swift detection of a burst with an optical afterglow
  43. VLA observations of GRB 060908
  44. GRB 060908, Swift-BAT refined analysis
  45. GRB 060908 - SDSS Pre-burst Observations
  46. GRB 060908: REM optical prompt observation
  47. GRB 060908: Swift detection of a burst with a bright optical counterpart
  48. GRB 060904A: Suzaku/WAM observation of the prompt emission
  49. GRB060906 , optical observation
  50. GRB 060906: Early RAPTOR optical limits
  51. GRB 060906, Swift-BAT refined spectral analysis
  52. GRB 060906: Swift/XRT Refined Analysis
  53. VLT redshift of GRB 060906
  54. GRB 060906, Swift-BAT refined analysis
  55. GRB 060906: Confirmation of P60 Optical Afterglow
  56. GRB 060906 (?): P60 Optical Afterglow Candidate
  57. GRB060904b, optical observations
  58. GRB060904A: Swift/UVOT optical observations
  59. GRB 060904A: Subaru NIR observation
  60. GRB 060904B: Swift-BAT refined analysis
  61. GRB 060904A: Refined analysis of the Swift-BAT burst
  62. GRB 060904A: Suzaku-XIS and -HXD observation plan
  63. GRB 060904A: P60 Observations
  64. GRB 060904B: Optical observations at Crni Vrh
  65. GRB 060904B: TAROT optical counterpart observations
  66. GRB060904B - SDSS Pre-Burst Observations
  67. GRB 060904: TAROT optical observations
  68. GRB 060904B: Swift detection of a burst with optical counterpart
  69. GRB060904 - SDSS Pre-Burst Observations
  70. GRB 060904: Swift detection of a bright burst
  71. GRB060901: Optical observations
  72. 060901: Swift UVOT followup observations
  73. GRB 060901: Swift/XRT Refined Analysis
  74. GRB 060901: Swift/XRT Position
  75. GRB 060901: a long GRB detected by INTEGRAL
  76. Two bright bursts from SGR 1806-20 detected with IBAS
  77. GRB 060605, observations using an Integral Field Unit
  78. GRB 060604: VLA Observation
  79. GRB 060814: Suzaku/WAM observation of the prompt emission
  80. GRB 060605: VLA Observation
  81. GRB 060707: VLA observation
  82. GRB 060825: VLA observations
  83. GRB060826 - SDSS Pre-Burst Observations
  84. GRB 060826(?): Swift detection of a possible burst
  85. GRB 060825: XRT Team Refined Analysis
  86. GRB 060825: Swift-BAT Refined Analysis
  87. GRB 060813: Swift/BAT, Konus-Wind, and Suzaku/WAM joint prompt spectral analysis
  88. GRB 060825: TNG optical observations
  89. GRB 060825: TAROT optical observations
  90. GRB 060825: P60 Observations
  91. GRB 060825: Swift detection of a burst
  92. GRB060801: host galaxy redshift
  93. GRB060729: analysis of XMM-Newton observation
  94. GRB 060729, SMARTS optical/IR observations
  95. GRB 060813: A long, bright GRB detected with Suzaku WAM
  96. Konus-Wind observation of GRB 060814
  97. GRB 060814: Refined analysis of the Swift-BAT burst
  98. GRB 060814: P60 Observations
  99. GRB 060814: P200 NIR Observations
  100. GRB060805B: 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