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"

28093 results found.

  1. GRB 090113: Swift detection of a burst
  2. GRB 090112: Fermi GBM detection
  3. GRB 090109: Fermi GBM detection
  4. GRB 090108B: Fermi GBM detection
  5. GRB 090111, Swift-BAT refined analysis
  6. GRB 090111: Swift UVOT Upper Limits
  7. GRB 090108: Fermi GBM Detection
  8. GRB 090111: Swift-XRT refined analysis
  9. GRB 090111: Enhanced Swift-XRT position
  10. GRB 090111: Swift detection of a burst
  11. GRB 090107B: Suzaku WAM observation of the prompt emission
  12. GRB090107B: Fermi GBM Detection
  13. GRB 090107B: Swift XRT afterglow confirmation
  14. GRB 090107B: Swift/UVOT Observations
  15. GRB 090107B: Swift-XRT detection of possible afterglow
  16. GRB 090107B: a long GRB localized by INTEGRAL
  17. Fermi/GBM detection of GRB 081226A
  18. Fermi/GBM detection of GRB 081225
  19. GRB 090107: Swift-BAT refined analysis
  20. GRB 081231: Fermi GBM Detection
  21. VLA radio upper limit on GRB 090102
  22. GRB 090102: GRT Optical Observation
  23. Swift triggered on the HMXB 1A 1118-61
  24. GRB 081229: Fermi GBM detection
  25. GRB 090102: P60 Imaging and P200 Spectroscopy
  26. GRB 090102 Observations from IAC80
  27. GRB 090102: GROND observations of the optical afterglow
  28. GRB 090102: Swift-BAT refined analysis
  29. GRB 090102: Swift XRT refined analysis
  30. GRB 090102: NOT redshift
  31. GRB 090102: Enhanced Swift-XRT position
  32. GRB 090102: REM observations of a bright afterglow
  33. GRB 090102: Swift detection of a burst with an optical counterpart
  34. GRB 090102: TAROT Calern observatory optical observations
  35. GRB 081230: GROND confirmation of the afterglow
  36. GRB 081230, Swift-BAT refined analysis
  37. GRB081230: Swift-XRT refined analysis
  38. GRB 081230 Swift/UVOT Observations
  39. GRB 081230: Enhanced Swift-XRT position
  40. GRB 081230: ROTSE-III Detection of Optical Counterpart
  41. GRB 081230: Swift detection of a burst
  42. GRB 081226C: Fermi GBM detection
  43. GRB 081228, Swift-BAT refined analysis
  44. VLA radio detection of GRB 081221
  45. GRB 081228: Swift/UVOT Upper Limits
  46. GRB 081228: Swift-XRT Team refined analysis
  47. GRB 081228: detection by GROND
  48. GRB 081228: Enhanced Swift-XRT position
  49. GRB 081228: TAROT Calern observatory optical observations
  50. GRB 081228: Swift detection of a burst
  51. VLA radio observation of GRB 081221
  52. GRB 081226B: Swift XRT and UVOT upper limits
  53. GRB 081224: Suzaku WAM observation of the prompt emission
  54. GRB 081226: Swift-XRT refined analysis
  55. GRB 081226A: Swift UVOT Upper Limits
  56. GRB 081226A: Swift-BAT refined analysis
  57. GRB 081226: GROND afterglow candidate
  58. GRB 081226: ROTSE-III Optical Limits
  59. GRB 081226: Swift detection of a possible short-hard burst
  60. GRB 080810: optical observations
  61. GRB 081211B: optical observations
  62. GRB 081224: Swift-XRT observation
  63. GRB 081222: MITSuME optical observation
  64. GRB 081224: Fermi GBM Detection & LAT Localization
  65. GRB 080810: optical observations
  66. Konus-Wind observation of GRB 081222
  67. GRB 081223: Fermi GBM detection
  68. GRB 081221: GROND observations
  69. VLA radio upper limit on GRB 081222
  70. GRB 081222: Fermi GBM observation
  71. GRB 081221: Probable host galaxy in Keck imaging
  72. GRB 081204C: Fermi GBM detection
  73. GRB 081222, Swift-BAT refined analysis
  74. GRB 081221, Swift-BAT refined analysis
  75. GRB081222 optical limit by "Pi of the Sky"
  76. GRB 081222: Swift XRT refined analysis
  77. GRB081221: Fermi GBM observation
  78. IPN triangulation of bright GRB 081215A
  79. GRB 081222: Faulkes Telescope South observations
  80. GRB 081221: Gemini-N nIR imaging
  81. GRB081222, optical observation
  82. GRB081203A: BTA observation
  83. Konus-Wind observation of GRB 081221
  84. GRB 081222: GROND Detection of the Optical/NIR Afterglow
  85. GRB081222: REM candidate afterglow
  86. GRB 081222: Swift detection of a burst with a bright optical afterglow
  87. GRB 081221: Enhanced Swift-XRT position
  88. GRB 081221: further NOT observations
  89. GRB 081221: NOT observations
  90. GRB 081221: Swift detection of a burst
  91. GRB 081217: Fermi GBM detection
  92. GRB 081211B: Further Swift-XRT analysis
  93. GRB 081215B: Fermi GBM detection
  94. GRB 081216: Suzaku WAM observation of the prompt emission
  95. GRB 081216 : Fermi GBM observation
  96. GRB 081215A: Fermi GBM detection
  97. GRB 081118: Zadko observations
  98. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  99. GRB 0811215A: MASTER prompt optical observations
  100. GRB 081215A: Andromeda inside Fermi error box: MASTER 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