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"

28051 results found.

  1. Swift/BAT possible detection of a weak burst GRB050430
  2. GRB050416a: Radio Detection
  3. GRB 050422: Swift-UVOT observation
  4. GRB 050422: Swift-BAT refined analysis
  5. Swift Detection of GRB 050422
  6. GRB 050421: SLOTIS observations
  7. GRB 050421: Further Analysis of IR imaging
  8. GRB050421: Radio Observations
  9. GRB050421: Radio Observations
  10. GRB 050421: IR Observations
  11. GRB 050421: Swift-BAT refined analysis
  12. GRB050421
  13. GRB 050421: early Swift XRT analysis results
  14. GRB 050421: NIR observations
  15. GRB050421: P60 Observations
  16. GRB 050421: BOOTES-2 simultaneous optical observations
  17. GRB 050416b: Tentative Swift XRT Position
  18. GRB 050315: potential host galaxy
  19. GRB050326: analysis of the XMM-Newton observation
  20. GRB050418: Null Optical Observations
  21. GRB050416A, optical observations
  22. GRB 050418: Swift-BAT refined analysis
  23. GRB 050416: Mitsume optical observation
  24. GRB050416B: IR observations
  25. GRB050412: Radio Observations
  26. GRB 050416: Swift/UVOT detection of afterglow emission
  27. GRB050416: Refined Swift-XRT analysis
  28. GRB 050416,optical observation
  29. GRB050416: P200 NIR Observations
  30. GRB 050416: Radio observations
  31. Swift BAT/XRT Detection of GRB 050416
  32. GRB 050412: PROMPT VRcIc Observations
  33. GRB 050408: Kuiper 1.5m observations
  34. GRB 050412: early Swift XRT analysis results
  35. GRB 050412: Early Optical/Ultraviolet Observations with
  36. GRB 050408: SDSS Field Calibration
  37. GRB050412: P60 Observations
  38. GRB 050412: Swift XRT Position
  39. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  40. GRB 050412: IR and Optical observations
  41. GRB 050412: IR Observations
  42. GRB050408: Radio Observations
  43. GRB 050401: Optical limit
  44. GRB050410: P60 Observations
  45. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  46. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  47. GRB050410: Radio Observations
  48. GRB050410: MASTER optical observations
  49. GRB 050410: Early observations with Swift-UVOT
  50. Swift-BAT detection of GRB 050410
  51. GRB 050408: Inconsistency of host galaxy identification
  52. GRB 050408: Subaru Observations
  53. GRB 050408: WIDGET simultaneous optical observations
  54. GRB 050408: Properties of the Host Galaxy
  55. GRB050408: Radio Observations
  56. GRB 050408: Swift XRT analysis
  57. GRB 050408: Optical limit at 20 min after the burst
  58. GRB050408: REM NIR and Optical observation
  59. GRB 050408,optical observation
  60. GRB 050408: Mercator Optical Observations
  61. GRB 050408: Optical afterglow confirmed
  62. GRB 050408: opitcal observation
  63. GRB 050408, optical observations
  64. GRB 050408 optical candidate
  65. GRB 050408: Swift XRT Position
  66. GRB050408: MASTER optical observations
  67. GRB050401: Radio Detection
  68. GRB 050406: early Swift XRT analysis results
  69. GRB 050406 BAT refined analysis
  70. GRB 050406: Early observations with Swift-UVOT
  71. Swift-BAT detection of GRB 050406
  72. GRB050401, radio observation at 4.8 GHz and 8.64 GHz
  73. GRB 050401: VLT spectroscopic redshift
  74. GRB 050401 BAT refined analysis
  75. GRB050401: TNG R-band observation
  76. GRB 050402: Early observations with Swift-UVOT
  77. Swift Trigger 113225: P60 Observations
  78. GRB 050401: Optical afterglow confirmed
  79. GRB 050401: Prompt XRT position
  80. Retraction of three Swift GRB triggers
  81. GRB050331: No Afterglow Detected
  82. Swift-BAT detection of GRB 050331b
  83. GRB 050331: Swift UVOT Source
  84. Swift-BAT detection of GRB 050331
  85. GRB 050326: Early observations with Swift-UVOT
  86. GRB 050326 XMM-Newton observation
  87. GRB 050326: Swift XRT Position
  88. GRB 050326 BAT refined analysis
  89. GRB050326: delayed XRT observation
  90. GRB050319, color indices
  91. GRB050319: optical observation, March 20-22
  92. GRB050319: RTT150 Optical Observations
  93. Swift-BAT trigger 112060 is not a real GRB
  94. GRB 050318: Swift-BAT refined analysis
  95. GRB050319: VLA Observations
  96. GRB050319: radio observation
  97. GRB 050319: Swift-UVOT detection of the afterglow
  98. GRB 050315: Variability Analysis of Swift BAT Time History
  99. GRB050319: Radio Observations
  100. GRB 050319: NIR afterglow candidate

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