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"

32488 results found.

  1. GRB 060403 Optical observations
  2. GRB 060403: MITSuME optical observation
  3. GRB060403: Optical Limit
  4. GRB060403: XRT refined analysis
  5. GRB 060403: Swift/UVOT upper limits
  6. SGR 1900+14: BAT observations
  7. GRB 060403: Refined analysis of the Swift-BAT burst
  8. GRB060403: Swift XRT refined position
  9. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  10. HETE trigger H4044: RTT150 optical observations
  11. GRB060331: Swift/UVOT upper limits
  12. H4044, a Repeat Outburst From The Source of H4043 (="GRB060331")
  13. Swift XRT observations of the HETE transient H4043
  14. HETE Trigger 4043: ROTSE-III Optical Limits
  15. H4043, an unusual high-energy transient observed by HETE
  16. GRB 060322: LNA optical limit
  17. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  18. INTEGRAL and XMM ToO observations of SGR1900+14
  19. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  20. GRB 060323 : WIDGET simultaneous optical observations
  21. GRB 060323: Early optical observation at Xinglong
  22. GRB060218, optical observations
  23. GRB 060322: Confirmation of Swift XRT afterglow
  24. GRB 060211A: optical observation
  25. GRB060323: optical limit
  26. GRB060211B: optical observation
  27. SGR 1900+14: CORRECTION to GCN 4923
  28. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  29. GRB060323: NOT optical observations
  30. GRB 060322: Swift XRT afterglow candidate
  31. GRB060323: P60 Observations
  32. GRB 060323: Swift/UVOT Observations
  33. GRB 060323: optical afterglow confirmed
  34. GRB060323: NOT observations
  35. GRB 060323: Optical Observations
  36. GRB 060323: Tautenburg OT candidate retraction
  37. GRB 060323: Refined analysis of the Swift-BAT burst
  38. GRB 060323: optical observations at TNG
  39. GRB 060323: Swift XRT refined analysis
  40. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  41. GRB 060323: Swift/XRT position
  42. GRB 060322: Refined analysis of the Swift-BAT burst
  43. GRB060323, optical observation
  44. GRB060206: optical observation
  45. GRB060218/SN2006aj: optical observations
  46. GRB 060218/SN 2006aj, LNA optical observation
  47. GRB060218: Refined photometric calibration of comparison stars
  48. GRB 060319: WHT K-band candidate afterglow
  49. GRB060319: Swift XRT refined analysis
  50. GRB060319: Swift/UVOT upper limits
  51. GRB 060319: Re-analysis of TNG data
  52. GRB060319: MASTER limit
  53. GRB 060319: Swift-BAT refined analysis
  54. GRB 060319 optical observations at TNG
  55. GRB060319 : Liverpool Telescope optical limit
  56. GRB060319 - SDSS Pre-burst Observations
  57. GRB060319: Swift/XRT position
  58. GRB060313: Radio Observations
  59. GRB 060313: early afterglow NIR upper limits with REM
  60. Konus-Wind observation of GRB 060313
  61. GRB060313: SSO 40inch Observations
  62. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  63. GRB 060313: PROMPT Observations
  64. GRB 060313: Swift/UVOT Observations
  65. GRB060313:Gemini South Observations
  66. GRB 060313: Swift-XRT team refined analysis
  67. GRB060313: optical observations of the afterglow candidate
  68. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  69. GRB 060313, SMARTS optical counterpart?
  70. GRB 060313: Possible optical counterpart
  71. GRB 060313: Swift XRT position
  72. GRB 060313, SMARTS optical/IR observations
  73. GRB060313: optical and near infrared observations with REM
  74. GRB060218: SARA Observations of SN2006aj
  75. GRB 060312: Refined analysis of the Swift-BAT burst
  76. GRB 060312: Swift XRT team refined analysis
  77. GRB060306: APO Ks-band Imaging Observations
  78. GRB 060312: ROTSE-III Optical Limits
  79. GRB 060306: SOAR Ks Observations
  80. GRB 060306: MAGNUM observations
  81. Swift/UVOT observations of GRB060306
  82. GRB 060306: Swift-BAT refined analysis
  83. GRB 060306: Swift-XRT team refined analysis
  84. GRB 060306: PROMPT Observations
  85. GRB 060218: RTT150 optical observations
  86. GRB060218: Ep,i - Eiso correlation
  87. GRB060223b: optical limit
  88. GRB060218/SN 2006aj: optical observation in V
  89. GRB060218/SN 2006aj: optical observation
  90. GRB 060121: HST observations
  91. GRB 060218 : GMRT observation [Correction and Improvement]
  92. GRB 060223b: Swift/UVOT Upper Limits
  93. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  94. GRB 060223B: Swift XRT possible afterglow
  95. GRB 060218/SN 2006aj: ABT observations
  96. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  97. GRB 060218 : Radio upper limits from GMRT
  98. GRB 060218/SN 2006aj: WIRO optical observations
  99. GRB 060218/SN 2006aj: RBO optical observations
  100. GRB 060204B: GETS early limit

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