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"

20357 results found.

  1. Swift Detection of GRB050509b: A short duration burst
  2. Swift Detection of the Burst GRB050509
  3. Swift-BAT detection of GRB 050507
  4. GRB 050502a: Swift XRT Upper Limit
  5. GRB 050505, simultaneous optical observation
  6. GRB050505: AAVSO observations
  7. GRB050416A : 1 GHz limit from GMRT
  8. GRB050505: Optical Afterglow Candidate
  9. GRB 050416b:Swift XRT afterglow upper limits
  10. GRB 050416b:Swift XRT afterglow upper limits
  11. Swift-BAT detection of GRB050505
  12. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  13. GRB050502b: Afterglow Confirmation
  14. GRB050502: P200 Observations (Correction)
  15. GRB050502: P200 Observations
  16. Swift UVOT observation of GRB 050504
  17. GRB050504: P60 Observations
  18. GRB 050504: A long GRB detected with INTEGRAL
  19. GRB (?) 050504: IR Observations, Intriguing Source
  20. GRB 050502b, Optical observations
  21. GRB050502a: P60 Observations (Correction)
  22. GRB050502a: P60 Observations
  23. GRB050502A: Optical Observations
  24. GRB050502B Swift-BAT refined analysis
  25. Swift Detection of the Bright Burst GRB050502b
  26. GRB 050502: ROTSE-III Detection of Possible Counterpart
  27. Swift/BAT possible detection of a weak burst GRB050430
  28. GRB050416a: Radio Detection
  29. Swift Detection of GRB 050422
  30. GRB 050421: SLOTIS observations
  31. GRB 050421: Further Analysis of IR imaging
  32. GRB050421: Radio Observations
  33. GRB050421: Radio Observations
  34. GRB 050421: IR Observations
  35. GRB050421
  36. GRB 050421: early Swift XRT analysis results
  37. GRB 050421: NIR observations
  38. GRB050421: P60 Observations
  39. GRB 050421: BOOTES-2 simultaneous optical observations
  40. Swift Detection of GRB050421
  41. GRB 050416b: Tentative Swift XRT Position
  42. GRB 050315: potential host galaxy
  43. GRB050326: analysis of the XMM-Newton observation
  44. GRB050418: Null Optical Observations
  45. GRB 050412: Chandra observations
  46. GRB050416A, optical observations
  47. GRB 050416: Mitsume optical observation
  48. GRB 050416 : optical observation at Xinglong observatory
  49. GRB050416B: IR observations
  50. GRB050412: Radio Observations
  51. GRB 050416: Swift/UVOT detection of afterglow emission
  52. GRB 050416,optical observation
  53. GRB050416: P200 NIR Observations
  54. GRB 050416: Radio observations
  55. Swift BAT/XRT Detection of GRB 050416
  56. GRB 050408: Kuiper 1.5m observations
  57. GRB 050412: Early Optical/Ultraviolet Observations with
  58. GRB 050408: SDSS Field Calibration
  59. GRB050412: P60 Observations
  60. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  61. GRB 050412: IR and Optical observations
  62. GRB 050412: IR Observations
  63. GRB050408: Radio Observations
  64. GRB050410: P60 Observations
  65. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  66. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  67. GRB 050410 R band Optical Observations
  68. GRB050410: Radio Observations
  69. GRB050410: MASTER optical observations
  70. GRB 050410: Early observations with Swift-UVOT
  71. GRB 050408: Inconsistency of host galaxy identification
  72. GRB 050408: Subaru Observations
  73. GRB 050408: WIDGET simultaneous optical observations
  74. GRB 050408: Properties of the Host Galaxy
  75. GRB050408: Radio Observations
  76. GRB050408: REM NIR and Optical observation
  77. GRB 050408,optical observation
  78. GRB 050408: Optical afterglow confirmed
  79. GRB 050408: opitcal observation
  80. GRB 050408, optical observations
  81. GRB 050408: Swift XRT Position
  82. GRB050408: MASTER optical observations
  83. GRB050401: Radio Detection
  84. GRB 050406: Early observations with Swift-UVOT
  85. Swift-BAT detection of GRB 050406
  86. GRB050401, radio observation at 4.8 GHz and 8.64 GHz
  87. GRB 050401 BAT refined analysis
  88. GRB050401: TNG R-band observation
  89. GRB 050402: Early observations with Swift-UVOT
  90. Swift Trigger 113225: P60 Observations
  91. GRB 050401: Optical afterglow confirmed
  92. GRB050331: No Afterglow Detected
  93. GRB 050331: Swift UVOT Source
  94. GRB 050326: Early observations with Swift-UVOT
  95. GRB 050326 XMM-Newton observation
  96. GRB 050326: Swift XRT Position
  97. GRB050326: delayed XRT observation
  98. GRB050319: optical observation, March 20-22
  99. GRB050319: RTT150 Optical Observations
  100. GRB050319: VLA Observations

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