Skip to main content
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"

19356 results found.

  1. GRB 050422: Swift XRT Position
  2. Swift Detection of GRB 050422
  3. GRB 050421: SLOTIS observations
  4. GRB050421: Radio Observations
  5. GRB050421: Radio Observations
  6. GRB 050421: Swift-UVOT observation
  7. GRB 050421: Swift-BAT refined analysis
  8. GRB 050421: ROTSE-III Optical Limits
  9. GRB 050421: early Swift XRT analysis results
  10. GRB 050421: BOOTES-2 simultaneous optical observations
  11. GRB 050421: Optical observations at the INT
  12. Swift Detection of GRB050421
  13. GRB 050416b: Tentative Swift XRT Position
  14. GRB050326: analysis of the XMM-Newton observation
  15. GRB 050418: Swift-BAT refined analysis
  16. Swift-BAT detection of the bright and long GRB 050418
  17. GRB 050416B: optical observations
  18. GRB 050416b: Swift-BAT refined analysis
  19. GRB 050416: Swift/UVOT refined analysis
  20. Swift-BAT detection of GRB 050416b
  21. GRB050412: Radio Observations
  22. GRB 050416: Swift/UVOT detection of afterglow emission
  23. GRB050416: Refined Swift-XRT analysis
  24. GRB050416: Maidanak optical observations
  25. GRB 050416: Swift-BAT refined analysis
  26. GRB 050416,optical observation
  27. GRB 050416: KAIT observations
  28. GRB 050416: Swift XRT Position
  29. GRB 050416: Radio observations
  30. Confirmation of OT for GRB050416
  31. GRB050416: P60 Afterglow Candidate
  32. Swift BAT/XRT Detection of GRB 050416
  33. GRB 050412: Subaru observations
  34. GRB 050412: optical limit
  35. GRB 050412: optical observations
  36. GRB 050408: refined XRT analysis, no jet break seen yet
  37. GRB 050412: early Swift XRT analysis results
  38. GRB 050412: Swift-BAT refined analysis
  39. GRB 050412: ANU 2.3m observations
  40. GRB 050412: Early Optical/Ultraviolet Observations with
  41. GRB 050412: retraction of UVOT transient report
  42. GRB 050412: UVOT transient not in XRT error circle
  43. GRB 050412: Swift XRT Position
  44. GRB050412: optical limit before and during GRB
  45. GRB050412: ROTSE-III Optical Limits
  46. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  47. GRB 050412: IR Observations
  48. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  49. GRB 050410, optical observations
  50. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  51. GRB 050410 R band Optical Observations
  52. GRB050410 : Null detection report
  53. GRB 050410, optical observations
  54. GRB050410: Radio Observations
  55. GRB 050408: Swift XRT measurement of possible jet break
  56. GRB050410: MASTER optical observations
  57. GRB 050410: Early observations with Swift-UVOT
  58. Swift-BAT detection of GRB 050410
  59. GRB 050410: Swift XRT Position
  60. GRB 050408: Properties of the Host Galaxy
  61. GRB 050408: Swift XRT analysis
  62. GRB 050408, optical observations
  63. GRB050408: REM NIR and Optical observation
  64. GRB 050408 Optical Observations
  65. GRB 050408: Optical afterglow confirmed
  66. GRB 050408, optical observations
  67. GRB 050408 optical candidate
  68. GRB 050408: Swift XRT Position
  69. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  70. GRB 050406: early Swift XRT analysis results
  71. GRB 050406 BAT refined analysis
  72. GRB 050406: Early observations with Swift-UVOT
  73. GRB 050406: Swift XRT Position
  74. Swift-BAT detection of GRB 050406
  75. Konus-Wind observation of GRB 050401
  76. GRB050401: Radio observation at 610 MHz with GMRT
  77. GRB 050401: VLT spectroscopic redshift
  78. GRB 050401 Optical Observations
  79. GRB050401: Maidanak optical observation
  80. GRB 050401 BAT refined analysis
  81. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  82. GRB 050402A: IR Observations
  83. GRB 050402: Early observations with Swift-UVOT
  84. Swift Trigger 113225: P60 Observations
  85. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  86. GRB 050401: Optical afterglow candidate
  87. Swift-BAT detection of GRB 050401
  88. GRB 050401: Prompt XRT position
  89. Retraction of three Swift GRB triggers
  90. Swift-BAT detection of GRB 050331b
  91. GRB 050331: Swift UVOT Source
  92. Swift-BAT detection of GRB 050331
  93. GRB 050331: Swift XRT Position
  94. Swift Data Publicly Available Starting April 5, 2005
  95. Konus-Wind observation of GRB 050326
  96. GRB050326: optical limit
  97. GRB 050326: Early observations with Swift-UVOT
  98. GRB 050326 XMM-Newton observation
  99. GRB 050326 : Planned XMM-Newton observation
  100. GRB 050326: Swift XRT Position

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