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"

19530 results found.

  1. GRB 071109: Swift-XRT possible X-ray counterpart
  2. GRB 071104: Swift-XRT Team Refined Analysis
  3. GRB 071104: Possible Swift UVOT Afterglow Candidate
  4. GRB 071104: Swift-XRT position
  5. Swift XRT and UVOT observations of GRB071028B
  6. GRB 071101, Swift-BAT refined analysis
  7. GRB 071101: Swift-XRT Team refined analysis
  8. GRB 071101: TAROT Calern observatory optical observations
  9. GRB 071101: Swift XRT position
  10. GRB 071101: BOOTES-2 prompt optical observations
  11. GRB 071101: a nearby galaxy
  12. GRB 071101: Swift detection of a burst
  13. GRB 071031, Swift-BAT refined analysis
  14. GRB 071031: Swift/UVOT detection of afterglow
  15. GRB 071031: Swift-XRT Team refined analysis
  16. GRB 071031: Swift detection of a burst with an optical counterpart
  17. GRB 071028B Swift-BAT detection of a burst
  18. Swift UVOT upper limits to GRB071028
  19. GRB 071028: Swift-XRT Team refined analysis
  20. GRB 071028, Swift-BAT refined analysis
  21. GRB 071028: Swift detection of a burst
  22. GRB 071025: Kuiper Telescope Optical Observations
  23. GRB 071018: Revised BAT position
  24. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  25. GRB071021: MARGE Optical Limits
  26. GRB071020, optical upper limit
  27. GRB 071025 Milagro GeV/TeV Observations
  28. Swift UVOT upper limits
  29. GRB 071025: Swift-XRT Team refined analysis
  30. GRB 071025, Swift-BAT refined analysis
  31. GRB 071025: Early Super-LOTIS Observations
  32. GRB 071025: ROTSE-III Refined Analysis
  33. GRB 071025: Swift XRT refined position
  34. GRB 071025: ROTSE-III Detection of Optical Counterpart
  35. GRB 071025: Swift detection of a burst
  36. GRB 071020: BTA spectroscopy
  37. Possible radio detection of GRB 071021 with the VLA
  38. Radio detection of GRB 071020 with the VLA
  39. GRB 071021: optical and NIR observations
  40. GRB 071021, Swift-BAT refined analysis
  41. GRB 071021: Swift-XRT Team refined analysis
  42. Konus-Wind observation of GRB 071020
  43. GRB 071021: Swift detection of a burst
  44. GRB 071020: Swift-XRT refined analysis
  45. GRB 071020, Swift-BAT refined analysis
  46. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  47. GRB071020 - SDSS Pre-burst Observations
  48. GRB 071020: Swift detection of a bright burst
  49. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  50. GRB 071018: Mercator Telescope optical observations
  51. Swift autonomous slewing re-enabled
  52. GRB 071018: Swift-XRT observation
  53. GRB 071017 - Swift XRT observations
  54. VLA radio observation of GRB 071018
  55. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  56. GRB 071018, Swift-BAT refined analysis
  57. GRB 071018?: Swift detection of a possible burst
  58. GRB 071010B: Suzaku WAM observation of the prompt emission
  59. GRB 071013: 3rd TLS Epoch - constraints on variability
  60. GRB 071013: TLS Upper Limit
  61. VLA detection of radio afterglow of GRB 071010B
  62. VLA non-detection of GRB 071011
  63. GRB 071013: Optical observations
  64. GRB 071013, Swift-BAT refined analysis
  65. GRB 071013: Swift detection of a burst
  66. GRB 071010C Swift-BAT detection of a burst
  67. GRB 071011: Swift-XRT refined analysis
  68. VLA non-detection of GRB 071010A
  69. GRB 071011, Optical afterglow
  70. GRB 071011: MARGE Optical Limits
  71. GRB 071011: XRT afterglow detection
  72. GRB 071011, Swift-BAT refined analysis
  73. GRB 071011: Early Super-LOTIS Observations
  74. GRB 071010B: Bright OT confirmed with TLS
  75. GRB 071011: Swift detection of a burst
  76. Optical Observation: GRB 071010
  77. Optical observations: GRB 071010A
  78. Konus-Wind observation of GRB 071010B
  79. GRB071010B: Swift/XRT detection
  80. GRB 071010B, Swift-BAT refined analysis
  81. GRB 071006, Swift-BAT refined analysis
  82. GRB 071010B: Swift detection of a burst
  83. GRB 071010: Swift-XRT observation
  84. GRB 071008, Swift-BAT refined analysis
  85. GRB 071010, Swift-BAT refined analysis
  86. GRB071008: Swift-XRT observation
  87. GRB 071010: TAROT La Silla observatory detection of the afterglow
  88. GRB 071010: Swift detection of a burst
  89. GRB 071006 Swift-BAT detection of a burst
  90. GRB071008: IAC80 observation
  91. GRB 071008: Swift detection of a burst
  92. GRB 071003: XRT refined analysis
  93. GRB070920A: MAGIC telescope GeV observation
  94. Radio detection of GRB 071003 with the VLA
  95. GRB 070810B: further XRT analysis
  96. Konus-Wind observation of GRB 071003
  97. GRB 071003: Swift XRT position
  98. GRB 071003, Swift-BAT refined analysis
  99. GRB 071003: MARGE Observations
  100. GRB 071003 Optical observations

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