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"

36784 results found.

  1. GRB060418: Swift XRT Team Refined Analysis
  2. GRB 060418, SMARTS continuing afterglow observations
  3. GRB 060418: PROMPT Detections
  4. GRB 060418, SMARTS optical/IR afterglow observations
  5. GRB060418: Magellan/MIKE Spectroscopic Redshift
  6. GRB060418 : LT optical afterglow observation
  7. GRB 060418: REM candidate afterglow
  8. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  9. GRB 060413: REM NIR Observations
  10. GRB 060413: Refined analysis of the Swift-BAT burst
  11. GRB 060413: Watcher UBVR observations
  12. GRB 060413: XRT refined analysis
  13. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  14. GRB 060413: Swift detection of a burst
  15. GRB060403: optical observations
  16. GRB 060403 Optical observations
  17. GRB 060403: MITSuME optical observation
  18. GRB060403: XRT refined analysis
  19. GRB 060403: Swift/UVOT upper limits
  20. GRB 060403: Refined analysis of the Swift-BAT burst
  21. GRB 060403: Swift detection of a burst
  22. GRB 060322: LNA optical limit
  23. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  24. GRB 060323 : WIDGET simultaneous optical observations
  25. GRB 060323: Early optical observation at Xinglong
  26. GRB060218, optical observations
  27. GRB 060322: Confirmation of Swift XRT afterglow
  28. GRB 060211A: optical observation
  29. GRB060323: optical limit
  30. GRB060211B: optical observation
  31. GRB060323: NOT optical observations
  32. GRB 060322: IAC80 optical observations
  33. GRB 060322: Swift XRT afterglow candidate
  34. GRB 060323: Swift/UVOT Observations
  35. GRB 060323: optical afterglow confirmed
  36. GRB060323: NOT observations
  37. GRB 060323: Optical Observations
  38. GRB 060323: Tautenburg OT candidate retraction
  39. GRB 060323: Refined analysis of the Swift-BAT burst
  40. GRB 060323: optical observations at TNG
  41. GRB 060323: Swift XRT refined analysis
  42. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  43. GRB 060323: Swift/XRT position
  44. GRB 060322: Refined analysis of the Swift-BAT burst
  45. GRB060323 - SDSS Pre-Burst Observations
  46. GRB 060323: Swift detection of a burst with a possible optical afterglow
  47. GRB 060322: Swift-BAT detection of a 200-sec burst
  48. GRB060219: optical observation
  49. GRB060206: optical observation
  50. GRB060218/SN2006aj: optical observations
  51. GRB 060218/SN 2006aj, LNA optical observation
  52. GRB060218: Refined photometric calibration of comparison stars
  53. GRB 060319: WHT K-band candidate afterglow
  54. GRB 060319: IAC-80 optical observations
  55. GRB060319: Swift XRT refined analysis
  56. GRB 060319: Re-analysis of TNG data
  57. GRB060319: MASTER limit
  58. GRB 060319: Swift-BAT refined analysis
  59. GRB 060319 optical observations at TNG
  60. GRB060319 : Liverpool Telescope optical limit
  61. GRB060319: MASTER optical observation
  62. GRB060319 - SDSS Pre-burst Observations
  63. GRB 060319: Swift detection of a burst
  64. GRB060313: Radio Observations
  65. GRB 060313: early afterglow NIR upper limits with REM
  66. IBAS Alert n. 3221: not a GRB
  67. Konus-Wind observation of GRB 060313
  68. GRB060313: SSO 40inch Observations
  69. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  70. GRB 060313: PROMPT Observations
  71. GRB 060313: Swift/UVOT Observations
  72. GRB060313:Gemini South Observations
  73. GRB 060313: Swift-XRT team refined analysis
  74. GRB060313: optical observations of the afterglow candidate
  75. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  76. GRB 060313, SMARTS optical counterpart?
  77. GRB 060313: Possible optical counterpart
  78. GRB 060313: Swift XRT position
  79. GRB 060313, SMARTS optical/IR observations
  80. GRB060313: optical and near infrared observations with REM
  81. GRB 060313: Swift-BAT detection of a bright short hard burst
  82. GRB060218: SARA Observations of SN2006aj
  83. GRB 060312: Refined analysis of the Swift-BAT burst
  84. GRB 060218/SN 2006aj, high resolution spectra
  85. GRB 060312: Swift XRT team refined analysis
  86. GRB060306: APO Ks-band Imaging Observations
  87. GRB 060312: ROTSE-III Optical Limits
  88. GRB 060312: Swift detection of a burst
  89. IBAS Alert n. 3218 : not a real GRB
  90. GRB 060306: SOAR Ks Observations
  91. Bright short hard GRB 060303: IPN localization and Konus spectrum
  92. GRB 060306: MAGNUM observations
  93. GRB060218: analysis of the XMM-Newton observation
  94. Swift/UVOT observations of GRB060306
  95. GRB 060306: Swift-BAT refined analysis
  96. GRB 060306: Swift-XRT team refined analysis
  97. GRB 060306: PROMPT Observations
  98. GRB 060306: Swift detection of a bright burst
  99. GRB 060218: RTT150 optical observations
  100. GRB060223b: optical limit

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