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"

45770 results found.

  1. GRB050922C: observation at MonteBoo
  2. INT 2.5m limit for GRB050922B
  3. GRB 050922B: optical limit
  4. GRB050922C: Optical Observations
  5. GRB 050922C: Swift XRT refined analysis
  6. HETE Fregate observations of GRB 050922C
  7. GRB 050922C: Swift-BAT refined analysis
  8. GRB 050922B: Swift-BAT refined analysis
  9. GRB050922C: optical observations
  10. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  11. GRB 050922C: optical obserations
  12. GRB 050922C: NOT optical observations
  13. GRB 050922A: Analysis of Swift/XRT TOO observation
  14. GRB 050922C: Swift detection of a bright burst
  15. GRB 050922C: ROTSE-IIId Refined Analysis
  16. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  17. GRB 050922B: ROTSE-III Optical Limits
  18. GRB 050922B,optical observation
  19. GRB050922B: Swift-BAT detection of a weak long burst
  20. Possible GRB 050922 detected by INTEGRAL
  21. GRB050918: Possible Swift/XRT detected afterglow
  22. GRB050820B: analysis of the XMM-Newton observation
  23. GRB050916: Swift/UVOT Upper Limits
  24. GRB 050916: Swift-BAT refined analysis
  25. GRB 050918 - A long GRB detected by INTEGRAL
  26. GRB 050915a: Radio Observations
  27. Swift-BAT trigger 155764 is not a GRB
  28. Swift-BAT trigger 155764 is probably not a GRB
  29. Swift trigger 155764: bad XRT centroid
  30. Swift-BAT trigger 155535 is definitely not a GRB
  31. GRB050916 : Swift-XRT refined analysis
  32. GRB 050916: XRT position
  33. GRB 050915b, SMARTS optical/IR observations of the XRT position
  34. GRB 050915B: Swift-BAT refined analysis
  35. GRB 050915B: Swift/UVOT Upper Limits
  36. GRB050916: Swift-BAT detection of a long weak burst
  37. GRB 050915a: IR Transient
  38. GRB 050915B: XRT position
  39. GRB 050915b, SMARTS optical/IR observations
  40. GRB050915B: Swift-BAT detection of a long bright burst
  41. GRB050915: Swift/UVOT upper limits
  42. GRB 050915: KAIT optical limit
  43. GRB 050915: IR Observations
  44. GRB 050915: Swift XRT refined analysis
  45. GRB 050915: Swift-BAT refined analysis
  46. GRB050915: P60 Optical Observations
  47. GRB050915, optical observations
  48. GRB050915: XRT position
  49. GRB 050915: ROTSE-III optical limits
  50. GRB 050915: Swift detection of a GRB
  51. GRB050911: Upper limit on X-ray afterglow
  52. Swift-BAT trigger 155072 ground analysis
  53. Swift-BAT trigger 155072 is probably not a GRB
  54. GRB050914: XRT position probably due to cosmic ray
  55. GRB 050911: LCO limits on a variable source
  56. GRB 050908: DEIMOS spectrum and further analysis
  57. Swift is in normal operation
  58. GRB050911: Swift UVOT followup observations
  59. GRB 050911, optical content of Swift/XRT error box
  60. GRB050911: Swift-XRT position
  61. GRB 050911: LCO observations
  62. GRB 050911, optical observations
  63. GRB 050911: Swift-BAT refined analysis
  64. Later Swift-BAT triggers 154632 and 154633 RETRACTION
  65. GRB 050911: z~0.16 cluster in the field
  66. GRB050911: Swift-BAT detection of a long burst
  67. GRB050908: detection of Swift/UVOT optical counterpart
  68. GRB 050910a: TAROT early optical limits
  69. RBO GRB 050908 observations
  70. WIRO observations in I of GRB 050908
  71. GRB 050906: Possible X-ray Counterpart
  72. GRB 050906: RTT150 optical observations
  73. GRB050908: Swift/UVOT Early upper limits
  74. GRB050908: VLT R-band decay index.
  75. GRB050908 : Swift-XRT refined analysis
  76. GRB 050908: Swift-BAT refined analysis
  77. GRB 050908: Optical observations
  78. Gemini Spectroscopy of GRB 050908
  79. GRB 050908: spectroscopic redshift
  80. GRB 050908: Prompt PROMPT Observations
  81. GRB 050908 : Swift XRT position
  82. GRB 050908: KAIT observations
  83. GRB 050908: P60 Confirmation of Optical Afterglow
  84. GRB 050908: Optical Observations
  85. GRB 050908: Swift detection of a burst
  86. Swift trigger 154073 is not a GRB
  87. GRB 050906: Optical observations at the Very Large Telescope
  88. GRB050904: CrAO optical observations
  89. GRB 050904 BAT refined analysis of complete data set
  90. GRB 050904: Subaru Optical Spectroscopy
  91. GRB 050906: MARGE Optical Limits
  92. GRB 050906: Swift-BAT refined analysis
  93. GRB 050906: Swift XRT upper limit
  94. GRB 050906: Radio Observations
  95. GRB 050904: Keck I-band Imaging
  96. GRB050906: P60 Observations
  97. GRB 050904: more VLT NIR observations
  98. GRB 050904: BOOTES early R-band observation
  99. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  100. GRB 050906: Bright galaxy in BAT error box

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