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"

25845 results found.

  1. GRB060110, optical observation
  2. GRB 060110: Optical observation
  3. GRB 060110: Correction
  4. Correction to GRB 060109 XRT analysis
  5. GRB 050110: IR Observations
  6. GRB 060110: Swift-BAT detection of a burst
  7. GRB 060109: Refined Swift-XRT analysis
  8. GRB 060109: Swift/UVOT upper limits
  9. GRB060109, optical observation
  10. GRB 060108: ISAS early observations and near IR upper limit
  11. GRB060108: P200 Ks Observations
  12. GRB 060108: early UKIRT K-band observations
  13. GRB 060108: Refined XRT analysis
  14. GRB 060108: VLT J-band observations
  15. GRB 060108: Mitsume optical observations
  16. GRB 060108: Swift/UVOT upper limits
  17. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  18. GRB060108: SDSS pre-burst observations
  19. GRB060108: Faulkes Telescope observation
  20. GRB060108, optical observation
  21. GRB060108: Swift detection of its 100th GRB
  22. Konus-Wind observation of GRB 060105
  23. GRB 060105: ISAS observations and near IR upper limit
  24. GRB 060105: Swift/UVOT upper limits
  25. GRB 060105: Mitsume optical observations
  26. GRB 060102 - no XRT afterglow
  27. GRB 060105: XRT refined analysis
  28. GRB060105: Suzaku-XIS and -HXD observation plan
  29. GRB060105, optical observation
  30. GRB060105: Swift detection of a bright long burst
  31. Swift-BAT trigger 175653 is probably not a GRB
  32. GRB 060102: Swift-BAT refined analysis
  33. Time Correction to GRB 060102
  34. GRB 051221B: Optical Observations with Kuiper 1.54m
  35. GRB 051227: Likely host galaxy underlying afterglow position
  36. GRB 051227: optical observation
  37. GRB 051227: optical afterglow
  38. GRB 051227: Magellan r'-band Imaging/Astrometry
  39. GRB 051227: refined analysis of VLT images
  40. GRB 051227: P60 Observations
  41. GRB 051227: MDM Observation
  42. GRB 051227: R-band object in the XRT error circle
  43. GRB 051227: Joint Swift-HETE Spectral Analysis
  44. GRB 051227: XRT refined analysis
  45. GRB 051227: Further analysis of the Swift-BAT burst
  46. GRB 051227: Refined analysis of the Swift-BAT burst
  47. GRB051227: SDSS pre-burst observations
  48. GRB 051227, optical observation
  49. GRB051117B: optical observation
  50. Konus-Wind observation of GRB 051221A
  51. GRB 051221A: MDM Optical Observations
  52. GRB051016: analysis of the XMM-Newton observation
  53. GRB 051221B: TAROT optical limits
  54. GRB 051221B: Refined analysis of the Swift-BAT burst
  55. Swift-BAT detection of a possible burst
  56. GRB 051221: Swift XRT refined analysis
  57. GRB 051221: Swift/UVOT upper limits
  58. GRB 051221: Improved astrometry of the IR counterpart
  59. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  60. GRB 051221: IR Observations at GRB+1hr
  61. GRB 051221: Swift detection of a bright short burst
  62. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  63. GRB051211A (=H3979): Refined Analysis
  64. GRB 051211B: optical afterglow
  65. Swift detection of an RS CVn flare star
  66. GRB051211A: possible optical candidate
  67. GRB 051215: near-infrared observations
  68. GRB051215 - SDSS pre-burst observations
  69. GRB 051215: Swift detection of a possible burst
  70. GRB051211B: XRT refined analysis
  71. GRB 051211B, optical observation
  72. GRB 051211A: Swift/UVOT upper limits
  73. GRB 051211B: Swift/UVOT upper limits
  74. GRB 051211A,optical observation
  75. GRB 051211B: Swift XRT confirmation of the afterglow
  76. GRB051211B: Liverpool Telescope observation
  77. GRB051211b: P60 Observations
  78. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  79. GRB 051211B: Swift XRT Observations
  80. GRB 051210: Swift/UVOT upper limits
  81. GRB 051210: Magellan Imaging
  82. GRB 051211: TAROT optical limits
  83. GRB 051211B: a possible optical detection by TAROT
  84. GRB 051211:IAC80 optical observations
  85. GRB 051210: SALT detection limit
  86. GRB 051210: Swift XRT refined analysis
  87. GRB 051210: FRAM early limit
  88. GRB051210: Swift UVOT Observation
  89. GRB 051210: Swift detection of a burst
  90. Swift XRT positions
  91. An extraordinary long burst on December 3 from SGR1806-20
  92. GRB 051127: Swift-BAT detection of a possible burst
  93. GRB051117B: Swift XRT refined analysis
  94. GRB051117b: No Swift/UVOT Detection
  95. GRB 051117A: Swift/UVOT Detection of an Afterglow
  96. GRB051008: Suzaku WAM observation of the prompt emission
  97. GRB 051021 Optical Observations
  98. GRB 051117B: R and I observations of possible host galaxy
  99. GRB 051117A: Refined analysis of the Swift-BAT burst
  100. GRB 051117B: Refined analysis of the Swift-BAT burst

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