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"

27043 results found.

  1. GRB 071101: TAROT Calern observatory optical observations
  2. GRB 071101: Swift XRT position
  3. GRB 071101: Swift detection of a burst
  4. GRB 071031, Swift-BAT refined analysis
  5. GRB 071031: Swift/UVOT detection of afterglow
  6. GRB 071020: MITSuME Akeno optical observations
  7. GRB 071031: VLT high-resolution spectroscopy
  8. GRB 071031: GROND detection in all bands
  9. GRB 071031: Swift detection of a burst with an optical counterpart
  10. GRB 071028B Swift-BAT detection of a burst
  11. GRB 071028: SARA observations of variable source
  12. Swift UVOT upper limits to GRB071028
  13. GRB 071028, Swift-BAT refined analysis
  14. GRB 071028: Swift detection of a burst
  15. GRB 071025: Kuiper Telescope Optical Observations
  16. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  17. GRB071021: MARGE Optical Limits
  18. GRB071020, optical upper limit
  19. GRB 071025: SARA VRI upper limits
  20. GRB 071025A: Complex Early-Time IR Behavior, Simultaneous with Gamma- and X-rays
  21. Swift UVOT upper limits
  22. GRB 071025, Swift-BAT refined analysis
  23. GRB 071025: Early Super-LOTIS Observations
  24. GRB 071025: ROTSE-III Refined Analysis
  25. GRB 071025a: PAIRITEL observations
  26. GRB 071025: ROTSE-III Detection of Optical Counterpart
  27. GRB 071025: Swift detection of a burst
  28. GRB 071020: SARA observations
  29. GRB071021: MITSuME Okayama Optical Upper Limits
  30. GRB 071021: optical and NIR observations
  31. GRB 071021, Swift-BAT refined analysis
  32. GRB 071021: Swift-XRT Team refined analysis
  33. Konus-Wind observation of GRB 071020
  34. GRB 071021: Faulkes Telescope South optical candidate
  35. GRB 071021: Swift detection of a burst
  36. GRB 071010B: Independent Confirmation of Break
  37. GRB 071020: Swift-XRT refined analysis
  38. GRB 071020, Swift-BAT refined analysis
  39. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  40. GRB071020 - SDSS Pre-burst Observations
  41. GRB 071020: Swift detection of a bright burst
  42. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  43. GRB 071018: Mercator Telescope optical observations
  44. GRB 071018: SARA observations
  45. GRB 071018: Swift-XRT observation
  46. GRB 071017 - Swift XRT observations
  47. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  48. GRB 071018, Swift-BAT refined analysis
  49. GRB 071018?: Swift detection of a possible burst
  50. GRB 071010B: Suzaku WAM observation of the prompt emission
  51. GRB 071011: MITSuME Optical Observations
  52. GRB 071010B: Photometry after 1.6 days
  53. GRB 071013, Swift-BAT refined analysis
  54. GRB 071013: Swift detection of a burst
  55. GRB 071010C Swift-BAT detection of a burst
  56. GRB 071011: Optical Limit after 13.95hrs
  57. GRB 071011: Swift-XRT refined analysis
  58. GRB 071010B: Optical Detection
  59. GRB 071011: Kanazawa Optical limits
  60. GRB 071011: MARGE Optical Limits
  61. GRB 071010B: Super-LOTIS upper limit
  62. GRB 071011, Swift-BAT refined analysis
  63. GRB 071011: Early Super-LOTIS Observations
  64. GRB 071011: Optical afterglow candidate
  65. GRB 071011: Swift detection of a burst
  66. Konus-Wind observation of GRB 071010B
  67. GRB 071010B, Swift-BAT refined analysis
  68. GRB 071006, Swift-BAT refined analysis
  69. GRB 071010B possible optical transient
  70. GRB 071010A: Keck/LRIS Photometry
  71. GRB 071010B: Swift detection of a burst
  72. GRB 071010: Swift-XRT observation
  73. GRB 071008, Swift-BAT refined analysis
  74. GRB 071010, Swift-BAT refined analysis
  75. GRB071008: Swift-XRT observation
  76. GRB 071010: TAROT La Silla observatory photometry of the afterglow
  77. GRB 071010: TAROT La Silla observatory detection of the afterglow
  78. GRB 071010: Swift detection of a burst
  79. GRB071008: IAC80 observation
  80. GRB 071008: Swift detection of a burst
  81. GRB 071003: XRT refined analysis
  82. GRB 070810B: further XRT analysis
  83. GRB 071003: Keck spectroscopy
  84. Konus-Wind observation of GRB 071003
  85. GRB071003: Faulkes Telescope North observations
  86. GRB 071003: Swift XRT position
  87. GRB 071003, Swift-BAT refined analysis
  88. GRB 071003: MARGE Observations
  89. GRB 071003: KAIT optical afterglow observations
  90. GRB 071003: Swift detection of a bright burst
  91. GRB 071001: Swift-XRT Team refined analysis
  92. GRB 071001, Swift-BAT refined analysis
  93. Faulkes Telescope South observations of GRB 071001
  94. GRB 071001: Swift detection of a burst
  95. GRB070925: Swift-XRT Position
  96. Update on Swift Status
  97. GRB 070920B: ROTSE-III Early Optical Limits
  98. Recent SGR1806-20 Activity
  99. GRB 070923, Swift-BAT refined analysis
  100. GRB 070920B: XRT 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