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"

28082 results found.

  1. GRB 050505: early time observations
  2. GRB 050505, simultaneous optical observation
  3. GRB050505: AAVSO observations
  4. GRB050416A : 1 GHz limit from GMRT
  5. GRB050505: Optical Afterglow Candidate
  6. GRB050505 Swift-BAT refined analysis
  7. GRB 050416b:Swift XRT afterglow upper limits
  8. GRB 050416b:Swift XRT afterglow upper limits
  9. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  10. GRB050502b: Afterglow Confirmation
  11. GRB050502: P200 Observations (Correction)
  12. GRB050502: P200 Observations
  13. GRB 050504 : R band observation at Lulin observatory
  14. Swift UVOT observation of GRB 050504
  15. GRB 050504, R band Observations
  16. GRB 050502b, V band Observations
  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. Renewal of SGR 1806-20 activity
  24. GRB050502B Swift-BAT refined analysis
  25. Swift UVOT refined analysis
  26. GRB 050502a : R band observation at Lulin observatory
  27. GRB 050502b : optical observation at Lulin observatory
  28. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  29. Swift Detection of the Bright Burst GRB050502b
  30. GRB 050502: INTEGRAL results
  31. GRB 050502: ROTSE-III Detection of Possible Counterpart
  32. Swift/BAT possible detection of a weak burst GRB050430
  33. GRB050416a: Radio Detection
  34. GRB 050422: Swift-UVOT observation
  35. GRB 050422: Swift-BAT refined analysis
  36. Swift Detection of GRB 050422
  37. GRB 050421: SLOTIS observations
  38. GRB 050421: Further Analysis of IR imaging
  39. GRB050421: Radio Observations
  40. GRB050421: Radio Observations
  41. GRB 050421: IR Observations
  42. GRB 050421: Swift-BAT refined analysis
  43. GRB050421
  44. GRB 050421: early Swift XRT analysis results
  45. GRB 050421: NIR observations
  46. GRB050421: P60 Observations
  47. GRB 050421: BOOTES-2 simultaneous optical observations
  48. GRB 050416b: Tentative Swift XRT Position
  49. GRB 050315: potential host galaxy
  50. GRB050326: analysis of the XMM-Newton observation
  51. GRB050418: Null Optical Observations
  52. GRB050416A, optical observations
  53. GRB 050418: Swift-BAT refined analysis
  54. GRB 050416: Mitsume optical observation
  55. GRB050416B: IR observations
  56. GRB050412: Radio Observations
  57. GRB 050416: Swift/UVOT detection of afterglow emission
  58. GRB050416: Refined Swift-XRT analysis
  59. GRB 050416,optical observation
  60. GRB050416: P200 NIR Observations
  61. GRB 050416: Radio observations
  62. Swift BAT/XRT Detection of GRB 050416
  63. GRB 050412: PROMPT VRcIc Observations
  64. GRB 050408: Kuiper 1.5m observations
  65. GRB 050412: early Swift XRT analysis results
  66. GRB 050412: Early Optical/Ultraviolet Observations with
  67. GRB 050408: SDSS Field Calibration
  68. GRB050412: P60 Observations
  69. GRB 050412: Swift XRT Position
  70. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  71. GRB 050412: IR and Optical observations
  72. GRB 050412: IR Observations
  73. GRB050408: Radio Observations
  74. GRB 050401: Optical limit
  75. GRB050410: P60 Observations
  76. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  77. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  78. GRB050410: Radio Observations
  79. GRB050410: MASTER optical observations
  80. GRB 050410: Early observations with Swift-UVOT
  81. Swift-BAT detection of GRB 050410
  82. GRB 050408: Inconsistency of host galaxy identification
  83. GRB 050408: Subaru Observations
  84. GRB 050408: WIDGET simultaneous optical observations
  85. GRB 050408: Properties of the Host Galaxy
  86. GRB050408: Radio Observations
  87. GRB 050408: Swift XRT analysis
  88. GRB 050408: Optical limit at 20 min after the burst
  89. GRB050408: REM NIR and Optical observation
  90. GRB 050408,optical observation
  91. GRB 050408: Mercator Optical Observations
  92. GRB 050408: Optical afterglow confirmed
  93. GRB 050408: opitcal observation
  94. GRB 050408, optical observations
  95. GRB 050408 optical candidate
  96. GRB 050408: Swift XRT Position
  97. GRB050408: MASTER optical observations
  98. GRB050401: Radio Detection
  99. GRB 050406: early Swift XRT analysis results
  100. GRB 050406 BAT 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