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"

20360 results found.

  1. GRB 081230: GROND confirmation of the afterglow
  2. GRB081230: Swift-XRT refined analysis
  3. GRB 081230 Swift/UVOT Observations
  4. GRB 081230: Enhanced Swift-XRT position
  5. GRB 081230: Swift detection of a burst
  6. GRB 081228, Swift-BAT refined analysis
  7. VLA radio detection of GRB 081221
  8. GRB 081228: Swift/UVOT Upper Limits
  9. GRB 081228: Swift-XRT Team refined analysis
  10. GRB 081228: detection by GROND
  11. GRB 081228: Enhanced Swift-XRT position
  12. GRB 081228: TAROT Calern observatory optical observations
  13. GRB 081228: Swift detection of a burst
  14. VLA radio observation of GRB 081221
  15. GRB 081226B: Swift XRT and UVOT upper limits
  16. GRB 081226: Swift-XRT refined analysis
  17. GRB 081226A: Swift UVOT Upper Limits
  18. GRB 081226: GROND afterglow candidate
  19. GRB 081226: ROTSE-III Optical Limits
  20. GRB 081226: Swift detection of a possible short-hard burst
  21. GRB 080810: optical observations
  22. GRB 081211B: optical observations
  23. GRB 081224: Swift-XRT observation
  24. GRB 081222: MITSuME optical observation
  25. GRB 081221: GROND observations
  26. VLA radio upper limit on GRB 081222
  27. GRB 081221: Probable host galaxy in Keck imaging
  28. GRB 081222, Swift-BAT refined analysis
  29. GRB081222 optical limit by "Pi of the Sky"
  30. Konus-Wind observation of very bright GRB 081215A
  31. GRB 081222: Swift XRT refined analysis
  32. IPN triangulation of bright GRB 081215A
  33. GRB 081222: Faulkes Telescope South observations
  34. GRB 081221: Gemini-N nIR imaging
  35. GRB081222, optical observation
  36. GRB081203A: BTA observation
  37. Konus-Wind observation of GRB 081221
  38. GRB 081222: GROND Detection of the Optical/NIR Afterglow
  39. GRB081222: REM candidate afterglow
  40. GRB 081222: Swift detection of a burst with a bright optical afterglow
  41. GRB 081221: Enhanced Swift-XRT position
  42. GRB 081221: further NOT observations
  43. GRB 081221: NOT observations
  44. GRB 081221: Swift detection of a burst
  45. GRB 081118: Zadko observations
  46. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  47. GRB 0811215A: MASTER prompt optical observations
  48. GRB 081215A: Andromeda inside Fermi error box: MASTER observations
  49. GRB 0811215A: Andromeda inside Fermi error box: MASTER observations
  50. Possible GRB 081211B: Swift/UVOT Upper Limits
  51. Possible GRB 081211B - Swift-XRT analysis
  52. GRB 081207: Fermi GBM detection
  53. GRB 081211B(?): Possible burst detection from Swift-BAT slew data
  54. GRB 081210, SMARTS optical/IR observations
  55. GRB 081211: Enhanced Swift-XRT position
  56. GRB 081211: Swift detection of a burst
  57. GRB081203B: optical observations
  58. GRB 081210: Enhanced Swift-XRT position
  59. GRB 081210: Swift detection of a burst with optical afterglow
  60. IPN triangulation of short hard GRB 081209
  61. GRB 081203A: optical observations
  62. GRB 081128: afterglow observations
  63. GRB081203A: Ashra-1 observation of early optical and VHE-neutrino emission
  64. GRB 081128: optical observation in CrAO
  65. GRB081203A: Optical observations at Ishigaki
  66. GRB 081204: GROND Observations
  67. Radio detection of GRB 081203B with the VLA
  68. GRB081203A: Radio upper limit at 15 GHz
  69. GRB 081204B: Fermi GBM detection
  70. GRB 081204: Swift/UVOT Upper Limits
  71. GRB 081204: Swift XRT afterglow confirmation
  72. GRB081203A: MITSuME optical observation
  73. GRB081203A: optical observation
  74. VLA Radio upper limit on GRB 081203A
  75. GRB 081203B: optical observations
  76. Swift/UVOT detection of GRB081203B
  77. GRB 081203B: Swift-XRT candidate afterglow.
  78. GRB 081203A: optical observations
  79. GRB 081203: Enhanced Swift-XRT position
  80. GRB 081130B: MASTER prompt optical observations
  81. GRB081203: optical observation
  82. GRB 081203: Swift detection of a burst with a bright optical counterpart
  83. Swift Trigger 335971: Swift/UVOT Observations
  84. GRB 081126: afterglow photometry
  85. VLA Radio upper limit on GRB 081126
  86. GRB 081130: MASTER VWF prompt optical observations Fermi GRB
  87. GRB 081128A: optical observations
  88. Trigger 335971: Swift possible detection of a burst
  89. GRB081128: Swift/UVOT Upper Limits
  90. GRB 081128: Swift-XRT refined analysis
  91. GRB 081128: Liverpool Telescope afterglow confirmation
  92. GRB081128: optical observations
  93. GRB 081128: Enhanced Swift-XRT position
  94. GRB 081128: Optical observation of xinglong TNT
  95. GRB 081128: Swift detection of a burst
  96. GRB 081126: GRT Optical Observation
  97. GRB 081127: Swift/UVOT Upper Limits
  98. GRB 081127: Swift-XRT refined analysis
  99. GRB 081127: Enhanced Swift-XRT position
  100. GRB 081127: Swift detection of a burst

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