Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

32766 results found.

  1. GRB 060108: Swift XRT position
  2. GRB 060105: Radio observations
  3. GRB 060105: MDM Observation
  4. Konus-Wind observation of GRB 060105
  5. GRB 060105: ISAS observations and near IR upper limit
  6. GRB 060105: Swift/UVOT upper limits
  7. GRB 060105: Mitsume optical observations
  8. GRB 060105: BAT refined analysis
  9. GRB 060102 - no XRT afterglow
  10. GRB 060105: XRT refined analysis
  11. GRB060105: Suzaku-XIS and -HXD observation plan
  12. GRB060105, optical observation
  13. GRB060105: Swift detection of a bright long burst
  14. Swift-BAT trigger 175653 is not an astrophysical source
  15. GRB 060102: MDM Observation
  16. Swift-BAT trigger 175653 is probably not a GRB
  17. GRB 060102: Swift-BAT refined analysis
  18. Time Correction to GRB 060102
  19. GRB 060102: Swift-BAT detection of a burst
  20. GRB051211B: optical observations
  21. GRB051227: SARA Observations
  22. GRB 051221B: Optical Observations with Kuiper 1.54m
  23. GRB 051227: Likely host galaxy underlying afterglow position
  24. GRB 051227: optical observation
  25. GRB051221B: Radio observations
  26. GRB 051221A: VLA Radio Observations
  27. GRB051227: Radio Observations
  28. GRB 051227: Confirmed fading from Gemini observations
  29. GRB051227: further analysis of VLT images
  30. GRB 051227: optical afterglow
  31. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  32. GRB 051227: Gemini observations
  33. GRB 051227: Keck Spectroscopy
  34. GRB 051227: Magellan r'-band Imaging/Astrometry
  35. GRB 051227: refined analysis of VLT images
  36. GRB 051227: P60 Observations
  37. GRB 051227: MDM Observation
  38. GRB 051227: R-band object in the XRT error circle
  39. GRB 051227: Joint Swift-HETE Spectral Analysis
  40. GRB 051227: XRT refined analysis
  41. GRB 051227: Refined analysis of the Swift-BAT burst
  42. GRB 051227, optical observation
  43. GRB051117B: optical observation
  44. Konus-Wind observation of GRB 051221A
  45. GRB 051221A: MDM Optical Observations
  46. GRB 051221A: Detection at 251nm with Swift UVOT
  47. GRB 051221A: Chandra Afterglow Position
  48. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  49. GRB 051221B: ROTSE-III Optical Limits
  50. GRB 051221B: TAROT optical limits
  51. GRB 051221A: WSRT Radio Observations
  52. GRB 051221: Redshift from Gemini
  53. GRB 051221: Continued fading of optical afterglow
  54. GRB 051221B: Refined analysis of the Swift-BAT burst
  55. Possible GRB 051221B: MDM Optical Detection
  56. GRB 051221A: RAPTOR Fading Counterpart Constraint
  57. Possible GRB 051221B: Swift XRT position
  58. GRB 051221: Discovery of fading optical afterglow
  59. GRB 051221: Swift XRT refined analysis
  60. GRB 051221: Swift/UVOT upper limits
  61. GRB 051221: Possible nearby cluster
  62. GRB 051221: Correction to GCN #4368
  63. GRB 051221: Gemini observations
  64. GRB 051221: Improved astrometry of the IR counterpart
  65. GRB051221: K-band source
  66. GRB 051221: XRT position
  67. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  68. GRB 051221: IR Observations at GRB+1hr
  69. Refined analysis of the SWIFT J1626.6-5156
  70. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  71. GRB051211A (=H3979): Refined Analysis
  72. GRB 051211B: optical afterglow
  73. GRB051211A: possible optical candidate
  74. Swift Trigger 172767 is not a GRB
  75. GRB 051215: near-infrared observations
  76. GRB051215 - SDSS pre-burst observations
  77. GRB 051215: A short GRB in a cluster?
  78. GRB051211B: Probable radio afterglow
  79. GRB051105: optical observations
  80. GRB 051213: Swift-BAT refined analysis
  81. GRB051211B: XRT refined analysis
  82. GRB051211B, RBO optical observations
  83. GRB 051211A: Swift/UVOT upper limits
  84. GRB 051211B: Swift/UVOT upper limits - correction
  85. GRB 051211B: Swift/UVOT upper limits
  86. GRB 051211A,optical observation
  87. GRB 051211B: Swift XRT confirmation of the afterglow
  88. GRB051211B: Liverpool Telescope observation
  89. GRB 051211b: RTT150 optical observations
  90. GRB051211b: P60 Observations
  91. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  92. GRB 051211B: Swift XRT Observations
  93. GRB 051210: Swift/UVOT upper limits
  94. GRB 051210: Magellan Imaging
  95. GRB 051211: TAROT optical limits
  96. GRB 051211B: a possible optical detection by TAROT
  97. GRB 051211: Swift XRT upper limit
  98. HETE SXC localization of GRB 051211 (=H3979)
  99. GRB 051210: SALT detection limit
  100. GRB 051210: Swift XRT refined analysis

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