Skip to main content
Circulars over Kafka event name backfill. 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').

18344 results found.

  1. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  2. Swift-BAT trigger 296491 is not a GRB
  3. GRB 071112C: TAROT Calern observatory optical observations
  4. Swift XRT follow-up observations of GRB071028B
  5. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  6. GRB 071112B: ROTSE-III Rapid Optical Limits
  7. GRB 071112C: Swift detection of a burst with an optical counterpart
  8. GRB 071112B: Swift detection of a short hard burst
  9. GRB 071112: Swift detection of a possible burst
  10. VLA IInd observation of INTEGRAL burst GRB 071109
  11. Swift/UVOT initial analysis of GRB071109
  12. GRB 071109: further Swift-XRT analysis
  13. No radio detection at Swift-XRT position
  14. GRB 071109: Swift-XRT possible X-ray counterpart
  15. GRB 071104: Swift-XRT Team Refined Analysis
  16. GRB 071104: Possible Swift UVOT Afterglow Candidate
  17. GRB 071104: Swift-XRT position
  18. Swift XRT and UVOT observations of GRB071028B
  19. GRB 071101, Swift-BAT refined analysis
  20. GRB 071101: Swift-XRT Team refined analysis
  21. GRB 071101: TAROT Calern observatory optical observations
  22. GRB 071101: Swift XRT position
  23. GRB 071101: BOOTES-2 prompt optical observations
  24. GRB 071101: a nearby galaxy
  25. GRB 071101: Swift detection of a burst
  26. GRB 071031, Swift-BAT refined analysis
  27. GRB 071031: Swift/UVOT detection of afterglow
  28. GRB 071031: Swift-XRT Team refined analysis
  29. GRB 071031: Swift detection of a burst with an optical counterpart
  30. GRB 071028B Swift-BAT detection of a burst
  31. Swift UVOT upper limits to GRB071028
  32. GRB 071028: Swift-XRT Team refined analysis
  33. GRB 071028, Swift-BAT refined analysis
  34. GRB 071028: Swift detection of a burst
  35. GRB 071025: Kuiper Telescope Optical Observations
  36. GRB 071018: Revised BAT position
  37. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  38. GRB071021: MARGE Optical Limits
  39. GRB071020, optical upper limit
  40. GRB 071025 Milagro GeV/TeV Observations
  41. Swift UVOT upper limits
  42. GRB 071025: Swift-XRT Team refined analysis
  43. GRB 071025, Swift-BAT refined analysis
  44. GRB 071025: Early Super-LOTIS Observations
  45. GRB 071025: ROTSE-III Refined Analysis
  46. GRB 071025: Swift XRT refined position
  47. GRB 071025: ROTSE-III Detection of Optical Counterpart
  48. GRB 071025: Swift detection of a burst
  49. GRB 071020: BTA spectroscopy
  50. Possible radio detection of GRB 071021 with the VLA
  51. Radio detection of GRB 071020 with the VLA
  52. GRB 071021: optical and NIR observations
  53. GRB 071021, Swift-BAT refined analysis
  54. GRB 071021: Swift-XRT Team refined analysis
  55. Konus-Wind observation of GRB 071020
  56. GRB 071021: Swift detection of a burst
  57. GRB 071020: Swift-XRT refined analysis
  58. GRB 071020, Swift-BAT refined analysis
  59. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  60. GRB071020 - SDSS Pre-burst Observations
  61. GRB 071020: Swift detection of a bright burst
  62. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  63. GRB 071018: Mercator Telescope optical observations
  64. Swift autonomous slewing re-enabled
  65. GRB 071018: Swift-XRT observation
  66. GRB 071017 - Swift XRT observations
  67. VLA radio observation of GRB 071018
  68. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  69. GRB 071018, Swift-BAT refined analysis
  70. GRB 071018?: Swift detection of a possible burst
  71. GRB 071010B: Suzaku WAM observation of the prompt emission
  72. GRB 071013: 3rd TLS Epoch - constraints on variability
  73. GRB 071013: TLS Upper Limit
  74. VLA detection of radio afterglow of GRB 071010B
  75. VLA non-detection of GRB 071011
  76. GRB 071013: Optical observations
  77. GRB 071013, Swift-BAT refined analysis
  78. GRB 071013: Swift detection of a burst
  79. GRB 071010C Swift-BAT detection of a burst
  80. GRB 071011: Swift-XRT refined analysis
  81. VLA non-detection of GRB 071010A
  82. GRB 071011, Optical afterglow
  83. GRB 071011: MARGE Optical Limits
  84. GRB 071011: XRT afterglow detection
  85. GRB 071011, Swift-BAT refined analysis
  86. GRB 071011: Early Super-LOTIS Observations
  87. GRB 071010B: Bright OT confirmed with TLS
  88. GRB 071011: Swift detection of a burst
  89. Optical Observation: GRB 071010
  90. Optical observations: GRB 071010A
  91. Konus-Wind observation of GRB 071010B
  92. GRB071010B: Swift/XRT detection
  93. GRB 071010B, Swift-BAT refined analysis
  94. GRB 071006, Swift-BAT refined analysis
  95. GRB 071010B: Swift detection of a burst
  96. GRB 071010: Swift-XRT observation
  97. GRB 071008, Swift-BAT refined analysis
  98. GRB 071010, Swift-BAT refined analysis
  99. GRB071008: Swift-XRT observation
  100. GRB 071010: TAROT La Silla observatory detection of the afterglow

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