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"

44375 results found.

  1. GRB 060814: source inside revised XRT error box
  2. GRB 060814: Possible IR counterpart
  3. GRB060805B: optical observations
  4. GRB060814: Swift/UVOT upper limits
  5. GRB 060813: pseudo-z from spectral parameters of the prompt
  6. GRB 060814: Swift XRT refined analysis
  7. GRB 060814: VLT optical limits
  8. GRB 060814 - SDSS Pre-Burst Observations
  9. GRB 060814: TAROT optical observations
  10. GRB 060814: Swift detection of a bright burst
  11. Konus-Wind observation of GRB 060813
  12. GRB060813: Swift/UVOT upper limits
  13. GRB 060813: Swift XRT refined analysis
  14. GRB 060813: Refined analysis of the Swift-BAT burst
  15. GRB 060813: Swift detection of a burst
  16. GRB051109B: Late-time Radio Observations
  17. Image of the dust-scattering halo around SGR 1806-20
  18. Second VLA limit on new radio point source in SGR 1806-20
  19. A dust-scattering halo detected around SGR 1806-20
  20. GRB 060805B: pseudo-z from spectral parameters of the prompt emission
  21. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  22. GRB060807: Possible Highly Significant X-ray Emission Lines
  23. GRB060714: optical observations
  24. IBAS Alert n. 3422: not a GRB
  25. GRB 060729: An update on the Swift XRT and UVOT observations
  26. GRB060717: optical observations
  27. GRB060807: Optical limiting magnitudes
  28. GRB 060805B: optical observation at Sierra Nevada
  29. GRB 060805B: XRT Team Analysis
  30. VLA Upper Limit on Outburst of SGR 1806-20
  31. GRB060806 is similar to previous activity of SGR1806-20
  32. GRB 060807: UVOT Upper limits
  33. GRB 060807: afterglow confirmation
  34. GRB 060807: XRT Team refined analysis
  35. GRB 060807: K- and R-band observations
  36. GRB 060807: Refined analysis of the Swift-BAT burst
  37. GRB060807: optical afterglow candidate
  38. GRB060806 = SGR1806-20
  39. GRB 060805B: RHESSI Spectral Fit
  40. GRB060807: optical upper limit in white light
  41. IPN triangulation of GRB060806 (long, exceptionally bright)
  42. GRB060807 - SDSS Pre-burst Observations
  43. GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
  44. GRB 060805B: Swift/UVOT Upper Limits
  45. GRB 060807, optical observation
  46. GRB 060807: Kanazawa R-band observation
  47. GRB 060807: optical limit
  48. GRB 060807: Swift detection of a burst
  49. GRB 060801: Second Epoch WSRT Radio Observations
  50. IPN triangulation of GRB060805B
  51. GRB060805 Liverpool Telescope observations
  52. GRB 060805: optical upper limit in R
  53. GRB 060805: XRT Team Refined Analysis
  54. GRB 060805: Swift-BAT Refined Analysis
  55. GRB 060805: Swift/UVOT Upper Limits
  56. GRB 060805: P60 Observations
  57. GRB 060805: KAIT observations
  58. GRB 060805 - SDSS Pre-Burst Observations
  59. GRB 060805: Swift detection of a burst
  60. GRB 060804: Swift UVOT observations
  61. GRB 060804: Swift-XRT Team Refined Analysis
  62. GRB 060804: Refined analysis of the Swift-BAT burst
  63. GRB 060804: Swift detection of a burst with a possible UVOT counterpart
  64. GRB 060728: Upper limits of the X-ray emission
  65. GRB 060801: no variability of optical sources
  66. GRB 060801: WSRT Radio Observations
  67. GRB 060801: XRT/SDSS Frame Offset and Refined XRT Position
  68. GRB060801: Radio Observations
  69. GRB 051109B: Bright spiral host galaxy at low redshift
  70. GRB 060801: optical observations at FORS2/VLT
  71. GRB060801: Swift/UVOT Upper Limits
  72. GRB 060801: optical observations at Hanle and Calar Alto
  73. GRB060801: optical upper limit in R
  74. GRB 060801: Swift XRT refined analysis
  75. GRB 060801: Refined analysis of the Swift-BAT short hard burst
  76. GRB 060801, optical observation
  77. GRB 060801: Kanazawa Optical Observation
  78. GRB 060801: Swift detection of a short burst
  79. GRB060729: ROTSE-III Observations of the Slow Optical Decay
  80. GRB 060218 / SN 2006aj Nebular Spectrum
  81. IBAS Alert n. 3415: not a GRB
  82. Swift-BAT trigger 221873 is not a GRB or a Transient
  83. GRB 060729 redshift
  84. GRB 060719: TORTOREM optical upper limits
  85. GRB 060729: Swift/UVOT Detections
  86. GRB 060729: Refined analysis of the Swift-BAT burst
  87. GRB 060729: Swift-XRT refined analysis
  88. GRB 060729 : Planned XMM-Newton observation
  89. GRB 060729: Swift/UVOT Observations
  90. GRB 060729: ROTSE-III Detection of Optical Counterpart
  91. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  92. GRB 060728: Swift/UVOT Upper Limits
  93. GRB 060728: Refined analysis of the Swift-BAT burst
  94. GRB 060728, SMARTS optical/IR observations
  95. Swift/XRT preliminary analysis
  96. GRB 060728: Swift detection of a burst
  97. GRB060614 ATCA Radio Limits
  98. GRB 060218 (SN 2006aj): IR afterglow detection six months after the
  99. GRB 060714: Swift/UVOT Observations
  100. GRB060719: prompt NIR observations with REM

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