Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

15742 results found.

  1. Swift triggered on the HMXB 1A 1118-61
  2. GRB 090102: Hobby-Eberly Telescope Spectroscopy
  3. GRB 090102: P60 Imaging and P200 Spectroscopy
  4. GRB 090102: GROND observations of the optical afterglow
  5. Swift UVOT observations of GRB 090102
  6. GRB 090102: NOT redshift
  7. GRB 090102: TAROT Calern observatory optical light curve
  8. GRB 090102: REM observations of a bright afterglow
  9. GRB 090102: Swift detection of a burst with an optical counterpart
  10. GRB 090102: TAROT Calern observatory optical observations
  11. GRB 081230 Swift/UVOT Observations
  12. GRB 081230: Swift/UVOT Detection of an Optical Afterglow
  13. GRB 081230: ROTSE-III Detection of Optical Counterpart
  14. GRB 081228: GROND confirmation of the optical/NIR afterglow
  15. VLA radio detection of GRB 081221
  16. GRB 081228: TAROT Calern observatory optical observations
  17. VLA radio observation of GRB 081221
  18. GRB 081226: Swift-XRT refined analysis
  19. GRB 081226A: Swift UVOT Upper Limits
  20. GRB 081226: GROND afterglow candidate
  21. GRB 081226: ROTSE-III Optical Limits
  22. GRB 081226: Swift detection of a possible short-hard burst
  23. GRB 080810: optical observations
  24. GRB 081211B: optical observations
  25. GRB 081222: MITSuME optical observation
  26. GRB 080810: optical observations
  27. GRB 081222:Optical afterglow observation
  28. VLA radio upper limit on GRB 081222
  29. GRB 081222: Gemini-South absorption redshift
  30. GRB 081221: Probable host galaxy in Keck imaging
  31. GRB081222 optical limit by "Pi of the Sky"
  32. Swift/UVOT observations of GRB 081221
  33. GRB 081222: Faulkes Telescope South observations
  34. GRB 081221: Gemini-N nIR imaging
  35. GRB081222, optical observation
  36. GRB081222: Swift/UVOT detection of an optical afterglow
  37. GRB081203A: BTA observation
  38. GRB 081222: GROND Detection of the Optical/NIR Afterglow
  39. GRB 081222: Swift detection of a burst with a bright optical afterglow
  40. GRB 081221: further NOT observations
  41. GRB 081118: Zadko observations
  42. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  43. GRB 0811215A: MASTER prompt optical observations
  44. GRB 081210: optical observations
  45. GRB 081007: Detection of a Supernova
  46. GRB 081211B(?): Possible burst detection from Swift-BAT slew data
  47. GRB 081210, SMARTS optical/IR observations
  48. GRB 081211: Swift/UVOT detection of an optical afterglow
  49. GRB 081210: Swift/UVOT refined analysis
  50. GRB081203B: optical observations
  51. GRB 081210: Swift detection of a burst with optical afterglow
  52. GRB 081203A: optical observations
  53. Radio observation of GRB 081121 with ATCA
  54. Radio observation of GRB 081118 with ATCA
  55. GRB 081128: afterglow observations
  56. GRB 081203B: Additional Gemini imaging
  57. Radio observation of GRB 081109 with ATCA
  58. Radio observation of GRB 081104 with ATCA
  59. Radio observation of GRB 081029 with ATCA
  60. Radio observation of GRB 081008 with ATCA
  61. GRB081203A: Ashra-1 observation of early optical and VHE-neutrino emission
  62. GRB 081203B: Gemini observations
  63. GRB 081128: optical observation in CrAO
  64. GRB081203A: Optical observations at Ishigaki
  65. GRB 081128: Optical afterglow observations
  66. GRB081203B: optical observations
  67. Radio detection of GRB 081203B with the VLA
  68. GRB081203A: Radio upper limit at 15 GHz
  69. GRB 081204: Swift/UVOT Upper Limits
  70. GRB081203A: MITSuME optical observation
  71. GRB 081203A: Optical observations of Xinglong TNT telescope
  72. GRB081203A: optical observation
  73. GRB 081203B: optical observations
  74. GRB 081203B: SDSS upper limits at the position of the optical afterglow
  75. GRB 081203A: optical observations
  76. Swift UVOT observations of GRB 081203A
  77. GRB 081130B: MASTER prompt optical observations
  78. GRB081203: optical observation
  79. GRB 081203: Swift detection of a burst with a bright optical counterpart
  80. GRB 081128: optical observation
  81. GRB 081130: MASTER VWF prompt optical observations Fermi GRB
  82. GRB 081128A: optical observations
  83. GRB 081128: Liverpool Telescope afterglow confirmation
  84. GRB081128: optical observations
  85. GRB081128 : Lulin optical follow-ups
  86. GRB 081128: Optical observation of xinglong TNT
  87. GRB 081126: GRT Optical Observation
  88. GRB 081126: Confirmation of the Optical Afterglow
  89. GRB 081126: optical observations
  90. GRB 081126: TAROT Calern observatory optical observations
  91. GRB 081121, SMARTS optical/IR afterglow observations
  92. GRB081121: Fermi GBM detection
  93. GRB081121: Refined Swift/UVOT observations
  94. GRB 081121: Swift-XRT refined analysis
  95. GRB 081121: Magellan Redshift
  96. GRB 081121: GROND observations
  97. GRB081121: Swift/UVOT observations
  98. GRB 081121: Swift detection of a burst
  99. GRB 081121: ROTSE-III Detection of Optical Counterpart
  100. GRB081118 : optical upper limit

Advanced

Download all Circulars as a .tar.gz archive:
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