Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"
  1. GRB 061006: Swift/UVOT optical observations
  2. Konus-Wind observation of the short hard GRB 061006
  3. GRB 061007 - FTS early brightening and power law decay
  4. GRB 061007 - Faulkes Telescope South Afterglow Confirmation
  5. GRB 061007: Swift detection of a burst with an optical counterpart
  6. GRB 061007: ROTSE-III Detection of Optical Counterpart
  7. GRB 061006: VLT observation
  8. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  9. GRB 061006: Swift-XRT Team Refined Analysis
  10. GRB061006 (Swift 232585) might be a short-hard GRB
  11. GRB 060930: near-IR afterglow candidate retraction
  12. GRB061006: Faulkes Telescope South Observations
  13. GRB 061006: Swift detection of a burst
  14. GRB 061004: Optical afterglow candidate and redshift
  15. GRB 061004: Las Campanas Optical/NIR Observations
  16. GRB061004: Swift/UVOT optical observations
  17. GRB 061004: Swift-XRT Team Refined Analysis
  18. GRB 061004, Swift BAT refined analysis
  19. GRB 061004: Nearby 2MASS Galaxy
  20. GRB 060928: Correction to GCN 5690
  21. GRB 061004: Swift detection of a burst
  22. GRB 060928: 2 pseudo-z from 2 detections spectral parameters
  23. Konus-Wind observation of GRB 060928
  24. GRB 060928: Suzaku/WAM observation of the prompt emission
  25. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  26. GRB 060928: Swift observations
  27. GRB 060928: RHESSI Spectral Fit
  28. IPN triangulation of GRB060928 (long, exceptionally bright)
  29. GRB061002: Swift UVOT followup observations
  30. GRB 060930: near-IR afterglow candidate
  31. GRB 061002: Swift-XRT Team Refined Analysis
  32. VLA observations of GRB 060926
  33. GRB061002 - SDSS Pre-Burst Observations
  34. GRB 061002, Swift-BAT refined analysis
  35. GRB061002: MASTER-VWF-Kislovodsk observations
  36. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  37. GRB 061002: Swift detection of a burst
  38. GRB 060908: Detection of a possible host
  39. GRB 060923A: Probable host galaxy in the R-band
  40. GRB 060807: Detection of a possible host galaxy
  41. GRB 060923A: VLA K-band Observations
  42. GRB060930: Faulkes Telescope South observation
  43. GRB 060930: Xinglong TNT optical observations
  44. GRB 060929: Further XRT Refined Analysis
  45. GRB 060929: Swift/UVOT Optical Observations
  46. GRB 060930: ROTSE-III Optical Limits
  47. GRB 060930: A long X-ray rich GRB detected by INTEGRAL
  48. GRB 060927 : GAO 150cm telescope optical observation
  49. GRB060929: Swift-XRT refined analysis.
  50. GRB 060929, Swift-BAT further refined analysis - late-time flare
  51. GRB 060929: TNG K-band observations
  52. GRB 060929, Swift-BAT refined analysis
  53. GRB060929: Optical limit
  54. GRB 060929: BART observation
  55. GRB 060929: MASTER-VWF-Kislovodsk observations
  56. GRB 060929: BOOTES-IR & OSN observations
  57. Liverpool Telescope observations of GRB 060929
  58. GRB 060929: Swift detection of a burst
  59. GRB060908: optical observations
  60. GRB 060729: An update on the late-time Swift observations
  61. GRB 060927: Spectroscopic redshift z=5.6
  62. IBAS Alert n.3501: not a GRB
  63. IBAS Alert n.3500: not a GRB
  64. GRB060923C: optical limit
  65. GRB060927: optical observations
  66. test of new software, grb
  67. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  68. GRB 060927: pseudo-z from spectral parameters of the prompt emission
  69. GRB 060927: Swift/UVOT Optical Observations
  70. GRB 060927: Early color
  71. GRB 060927: Swift XRT Team refined analysis
  72. GRB 060927 optical limit
  73. GRB 060927, Swift-BAT refined analysis
  74. GRB 060927: Xinglong TNT optical observations
  75. GRB060926: improved redshift
  76. GRB 060927, optical observation
  77. GRB 060927: Possible host galaxy (star?) in the SDSS
  78. GRB 060927 : Kiso optical observation
  79. GRB060927: Faulkes Telescope South observation
  80. GRB 060926: MASTER: first minutes decay
  81. GRB060927 - SDSS Pre-Burst Observations
  82. GRB 060927: optical afterglow confirmation
  83. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  84. Swift XRT boresight
  85. GRB 060927: Swift detection of a burst
  86. GRB060926: VLT redshift
  87. GRB 060926: Swift-UVOT Detections
  88. GRB 060923A: Schedule of Spitzer Space Telescope Observations
  89. GRB 060926: OPTIMA-Burst -- further observations
  90. GRB 060926: Swift XRT refined analysis
  91. GRB 060926, Swift-BAT refined analysis
  92. GRB 060923A: Radio Observations
  93. GRB 060926: MASTER OT alert observation
  94. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  95. GRB 060912A: Redshift of probable host galaxy
  96. GRB 060926: BOOTES-IR observations
  97. GRB 060926: Watcher observations
  98. GRB060926 OPTIMA-Burst optical observation
  99. GRB 060926: MASTER optical observation
  100. GRB 060926: Swift detection of a burst

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