Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
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"

20121 results found.

  1. GRB 060427: Refined analysis of the Swift-BAT burst
  2. GRB 060427, optical observation
  3. GRB 060427: Swift detection of a burst
  4. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  5. GRB 060424: Refined analysis of the Swift-BAT burst
  6. GRB 060424: Swift detection of a burst
  7. GRB 060421: TTT Observations
  8. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  9. GRB060421: Swift/UVOT observations
  10. Konus-Wind observation of GRB 060418
  11. GRB(?) 060421: Swift detection of a burst
  12. GRB 060418: Radio Observations
  13. GRB060418, BVRcIc field calibration
  14. GRB060418: Swift/UVOT Observations
  15. GRB060418: Optical Observations
  16. GRB 060418: FRAM early afterglow observation
  17. VLT/UVES observations of GRB060418
  18. GRB 060418: PROMPT Detections
  19. GRB060418 : LT optical afterglow observation
  20. GRB 060418: REM candidate afterglow
  21. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  22. GRB060413: Swift/UVOT upper limits
  23. GRB 060413: REM NIR Observations
  24. GRB 060413: Swift detection of a burst
  25. GRB 060403 Optical observations
  26. GRB 060403: MITSuME optical observation
  27. GRB060403: Optical Limit
  28. GRB 060403: Swift/UVOT upper limits
  29. SGR 1900+14: BAT observations
  30. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  31. GRB 060403: Swift detection of a burst
  32. HETE trigger H4044: RTT150 optical observations
  33. GRB060331: Swift/UVOT upper limits
  34. Swift XRT observations of the HETE transient H4043
  35. HETE Trigger 4043: ROTSE-III Optical Limits
  36. H4043, an unusual high-energy transient observed by HETE
  37. GRB 060322: LNA optical limit
  38. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  39. GRB 060323 : WIDGET simultaneous optical observations
  40. GRB 060323: Early optical observation at Xinglong
  41. GRB 060322: Confirmation of Swift XRT afterglow
  42. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  43. GRB060323: NOT optical observations
  44. GRB 060322: IAC80 optical observations
  45. GRB 060322: Swift XRT afterglow candidate
  46. GRB060323: P60 Observations
  47. GRB 060323: Swift/UVOT Observations
  48. GRB 060323: optical afterglow confirmed
  49. GRB060323: NOT observations
  50. GRB 060323: Optical Observations
  51. GRB 060323: Refined analysis of the Swift-BAT burst
  52. GRB 060323: optical observations at TNG
  53. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  54. GRB 060322: Refined analysis of the Swift-BAT burst
  55. GRB060323, optical observation
  56. GRB060323 - SDSS Pre-Burst Observations
  57. GRB 060323: Swift detection of a burst with a possible optical afterglow
  58. GRB 060218/SN 2006aj, LNA optical observation
  59. GRB060218: Refined photometric calibration of comparison stars
  60. GRB 060319: WHT K-band candidate afterglow
  61. GRB060319: Swift/UVOT upper limits
  62. GRB 060319 optical observations at TNG
  63. GRB060319 : Liverpool Telescope optical limit
  64. GRB060319 - SDSS Pre-burst Observations
  65. GRB060319: Swift/XRT position
  66. GRB060313: Radio Observations
  67. GRB 060313: early afterglow NIR upper limits with REM
  68. Konus-Wind observation of GRB 060313
  69. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  70. GRB 060313: Swift/UVOT Observations
  71. GRB 060313, SMARTS optical/IR observations
  72. GRB060313: optical and near infrared observations with REM
  73. GRB 060313: Swift-BAT detection of a bright short hard burst
  74. GRB060218: SARA Observations of SN2006aj
  75. GRB 060312: Swift XRT team refined analysis
  76. GRB060306: APO Ks-band Imaging Observations
  77. GRB 060312: ROTSE-III Optical Limits
  78. Bright short hard GRB 060303: IPN localization and Konus spectrum
  79. GRB 060306: MAGNUM observations
  80. GRB060218: analysis of the XMM-Newton observation
  81. Swift/UVOT observations of GRB060306
  82. GRB 060306: Swift-XRT team refined analysis
  83. GRB 060306: Swift detection of a bright burst
  84. GRB060218: Ep,i - Eiso correlation
  85. GRB060223b: optical limit
  86. GRB 060223b: Swift/UVOT Upper Limits
  87. GRB 060218/SN 2006aj: K-380 optical observations
  88. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  89. GRB200618: optical polarimetry and photometry
  90. GRB 060223B: Swift XRT possible afterglow
  91. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  92. GRB 060218 : Radio upper limits from GMRT
  93. GRB 060223A:Xinglong optical limits
  94. GRB 060223a: Swift/UVOT refined analysis
  95. GRB 060223B: Swift detection of a bright burst
  96. GRB 060218: rebrightening
  97. GRB 060219: Swift-BAT refined analysis
  98. GRB 060218: Decline in r-band flux
  99. GRB060219: SARA Observations
  100. GRB 060219: Swift/UVOT Upper Limits

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